Innovia will now consolidate all its bubble film volume into its UK and Australian operations
has confirmed its plans to permanently close its Innovia business operations in Merelbeke
The move will be undertaken during the first quarter (Q1) of next year
Innovia specialises in manufacturing multilayered surface-engineered films and is a producer of biaxially-oriented polypropylene films offering products made using bubble
and metallising facilities located across the UK
CCL first announced signing a definitive agreement to acquire UK-based Innovia Group in December 2016 for approximately C$1.13bn ($844m)
Following the latest decision to close the business in Belgium
Innovia will now consolidate all its ‘bubble film’ volume into its existing UK and Australian operations
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Innovia is expected to record approximately $17m to $20m of incremental operating income annually
the company is expecting to register an estimated non-cash
goodwill impairment expense of nearly $120m and a one-time pretax restructuring charge
This one-time charge covers closure cash costs
as well as employee severance accruals ranging between $25m and $30m
CCL CEO and president Geoffrey T Martin said: “Our operation in Belgium is a smaller two-bubble line plant using older equipment with the highest cost to serve in our global network
“Given the softer post-Covid demand environment
it is essential we optimise existing capacity for the future
while enhancing financial performance for 2024
planned new technology investments in Germany and Mexico
plus the impact of building Ecofloat volume in Poland
should drive further gains in our operational effectiveness and profitability in 2025 and beyond.”
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To report the presence of urolithiasis in dogs long-term after gradual attenuation of congenital extrahepatic portosystemic shunts (cEHPSS)
25 client-owned dogs that underwent gradual attenuation of a cEHPSS
of which 19 had a closed cEHPSS and 6 developed multiple acquired portosystemic shunts (MAPSS) following surgery
A retrospective study with prospective follow-up was performed
Dogs that underwent cEHPSS surgery and had their postoperative cEHPSS status determined by transsplenic portal scintigraphy or CT angiography 3 months postoperatively were prospectively contacted and invited for a long-term follow-up visit (a minimum of 6 months postoperatively)
and during the prospective follow-up visit a thorough history
and ultrasonography of the urinary tract were performed to assess the presence of urinary signs and urolithiasis
1 of 19 (5%) dogs with closed cEHPSS and 4 of 6 (67%) dogs with MAPSS had urolithiasis at long-term follow-up
Three (50%) dogs with MAPSS developed new uroliths
dogs with closed cEHPSS that initially presented with and without urolithiasis had significantly less urolithiasis compared to dogs with MAPSS (P = .013 and P = .010
In the 4 dogs with closed cEHPSS that initially presented with nephrolithiasis
nephroliths became smaller or were no longer visible at the long-term follow-up visit
Dogs that developed MAPSS following cEHPSS surgery are at greater risk of urolithiasis compared to those with closed cEHPSS
ammonium urate uroliths might dissolve if portosystemic shunting ceases to exist
it is unclear whether dogs are still vulnerable to developing ammonium urate uroliths following successful cEHPSS surgery and whether nephroliths remain or dissolve over time in the absence of portosystemic shunting
it is unclear whether dogs that develop MAPSS after cEHPSS attenuation are at greater risk of recurrent urolithiasis
Our study aimed to document the presence of urolithiasis in dogs long-term after cEHPSS attenuation
A retrospective study with a prospective long-term follow-up was set up and approved by the local ethical and deontological committee (EC 2018-77
Records of the clinic were searched for dogs that underwent surgical attenuation of a cEHPSS between January 2012 and December 2018
Dogs were eligible for inclusion if the postoperative PSS status was determined by transsplenic portal scintigraphy or CT angiography a minimum of 3 months postoperatively and if the surgery was performed at least 6 months prior to study inclusion
Dogs with MAPSS (pU+/−) were only included if they developed these following surgical attenuation of a cEHPSS
As only a limited number of dogs with MAPSS were available that met the inclusion criteria
owners of all these dogs were contacted by phone and invited for a prospective follow-up visit
a number of dogs with closed cEHPSS with (cU+) and without urolithiasis (cU–) before or at the time of cEHPSS attenuation were listed
It was decided to include a similar number of dogs with closed cEHPSS with and without a history of preoperative urolithiasis
As the minority of these dogs did not have urolithiasis before or at the time of cEHPSS attenuation
all owners of these dogs were contacted by phone and invited for a prospective follow-up visit
dogs with closed cEHPSS that had a history of preoperative urolithiasis were matched to the previous dogs included
based on the time between the cEHPSS attenuation and the prospective follow-up visit
to achieve a comparable average follow-up time between all dogs
Owners of the latter dogs were contacted by phone and invited for a prospective follow-up visit
All owners that came for the prospective follow-up visit signed an informed consent that contained all details about the study
and hence all owners gave consent to analyze all retrospectively available data and perform all prospective investigations that were part of the current study (for details
Owners of dogs were invited for a prospective follow-up visit between June 2019 and January 2020
and a thorough history was taken by the primary author
who filled out the questionnaire together with the owners
If urinary tract disease occurred during the period between cEHPSS attenuation and the prospective follow-up visit
the referring veterinarian was contacted to obtain the results of the investigations
To quantify the severity of urinary complaints
a urinary score (0 to 18) was calculated for each dog before cEHPSS attenuation and at time of the prospective follow-up visit based on answers available in the questionnaires
Urinary signs that occurred often were assigned 2 points
and those that occurred occasionally were assigned 1 point
Ammonia was measured immediately after blood sampling using a portable laboratory device (PocketChem BA; A Menarini Diagnostics srl)
Ultrasonography of the urinary tract was performed in all dogs by a European College of Veterinary Diagnostic Imaging diplomate (ES) to assess the presence of urolithiasis and echogenicity of urine and reassess cEHPSS closure
the size and location were recorded and abdominal plain radiographs were performed to assess radiopacity
Ultrasound-guided cystocentesis and in-house urinalyses were performed in all dogs
manual semiquantitative dipstick urinalysis and microscopic native
and diff-quick stained sediment examination
completed within 30 minutes after collection
it was decided to report results as nonparametric data
Statistical analysis was performed using SPSS Statistics (version 26; IBM)
Kruskal-Wallis tests were performed to assess differences between groups (cU+
the presence of urolithiasis at the time of surgical attenuation of the cEHPSS and the prospective follow-up visit
and the time between cEHPSS attenuation and the prospective follow-up visit
pairwise comparisons were performed with the Bonferroni correction
Wilcoxon matched-pair signed rank tests were performed
Results with a P ≤ .05 were considered significant
Owners of 26 dogs were contacted. The owner of 1 dog with MAPSS elected not to participate in the study because of the anxious nature of the dog, and thus a total of 25 dogs were included, of which 17 dogs had urolithiasis before or at the time of cEHPSS attenuation (12/19 dogs in which surgical attenuation resulted in a closed cEHPSS and 5/6 dogs that developed MAPSS; Table 1)
Breeds of dogs included the following: Yorkshire Terrier (n = 5); Chihuahua
and Maltese (3 each); Bichon Frise and mixed-breed dog (2 each); and Border Collie
There was no difference between the groups in age (P = .340)
and time between cEHPSS attenuation and the prospective follow-up visit (P = .851)
uroliths were previously diagnosed and removed by the referring veterinarian
cystotomy was performed at the time of cEHPSS attenuation
An ameroid constrictor was placed in 17 of 25 (68%) dogs
Demographic data of included dogs in this study with a history of a surgical attenuation of congenital extrahepatic portosystemic shunts (cEHPSS)
MAPSS = Multiple acquired portosystemic shunts
U+ = Dogs with confirmed urolithiasis before or at the time of cEHPSS attenuation
U– = Dogs with no history of urolithiasis before or at the time of cEHPSS attenuation
or urinary signs a median of 36 months (13 to 103 months) after cEHPSS attenuation
See Table 1 for key
Seven dogs still received a liver-supportive treatment (Table 2)
All dogs but one received a liver-supportive diet
One dog with MAPSS received a liver-supportive diet until 12 months after cEHPSS attenuation when ammonium urate cystoliths were surgically removed and after which the diet was changed to a urolithiasis-prevention diet
At the time of cEHPSS attenuation, 23 of 25 (92%) dogs showed urinary complaints, and at the time of the prospective follow-up visit, 12 of 25 (48%) dogs had a history of urinary complaints in the period from 3 months postoperatively to the prospective follow-up visit. Six of those dogs had a closed cEHPSS (6/19 [32%]) and the other 6 had MAPSS (6/6 [100%]; Tables 2 and 3)
One of the dogs with MAPSS suffered from recurrent clinical bacterial cystitis
At the time of cEHPSS diagnosis as well as the prospective follow-up visit
the urinary scores were not different between the different groups (P = .347 and P = .082
urinary scores of cU+ dogs significantly decreased (P = .005 vs P = .223 for cU– and P = .248 for pU+/−)
Number of dogs presented with urinary complaints at the time of cEHPSS diagnosis compared to the period between the time of cEHPSS attenuation and the time of the prospective follow-up visit with a median time of 36 months (13 to 103 months)
Follow-up = At time of prospective follow-up visit
See Table 1 for remainder of key
Blood examinations were performed at the time of the prospective follow-up visit (Table 4)
One (5%) dog with closed cEHPSS had hyperammonemia; nevertheless
neither MAPSS nor clear indications for recanalization of the cEHPSS were found on the basis of abdominal ultrasonography
further medical imaging was refused by the owner as the dog was clinically doing very well
Hyperammonemia was present in 4 of 6 (67%) dogs with MAPSS
A statistically significant difference in fasting ammonia concentrations was present between pU+/− and both cU+ and cU– (P = .018 and P = .014
Median (range) of selected blood and urine variables a median of 36 months (13 to 103 months) after cEHPSS attenuation
See Table 1 for remainder of key
Urinalysis was performed at the time of the prospective follow-up visit (Table 4)
Microscopic hematuria was found in 13 of 25 (52%) dogs
Microscopic analysis of the sediment revealed some artifacts in 1 dog with closed cEHPSS
most likely due to dirty slides or staining
although the presence of ammonium biurate crystals could not be completely ruled out
One dog with MAPSS had a previous episode of bacterial cystitis (Escherichia coli
treated with amoxicillin–clavulanic acid) but was asymptomatic at the time of the prospective follow-up visit
a moderate number of amorphous crystals and a large number of rods were present
although only a small number of erythrocytes and leukocytes were seen
Urine culture and sensitivity testing revealed the presence of multiresistent E coli
Of the 4 dogs with crystalluria at the time of the prospective follow-up visit
Only in 1 dog quantitative urolith analysis was performed because the dog showed clinical signs (urinary score 10) and revealed the presence of calcium oxalate crystals
which did not match the type of crystalluria (amorphous) at the time of the prospective follow-up visit
Before cEHPSS attenuation, uroliths were visible on abdominal ultrasonography in 17 of 25 (68%) dogs, with 5 dogs having uroliths in > 1 location. In 15 of 25 (60%) dogs, echoic foci were present in the urinary bladder. In 3 dogs, echoic foci were seen in the absence of urolithiasis (Table 5)
the median urinary score of dogs with echoic foci was 5 (2 to 18) and the median urinary score of dogs with urolithiasis was 5.5 (0 to 18)
and urinary crystals in 25 dogs a median of 36 months (13 to 103 months) after cEHPSS attenuation
*The presence of ammonium biurate crystals could not be completely ruled out in 1 dog because of the presence of artifacts
See Table 1 for remainder of key
At time of the prospective follow-up visit, uroliths were seen in 5 of 25 (20%) dogs (Table 5)
of which 4 dogs had uroliths in multiple locations
One of the 19 (5%) dogs with closed cEHPSS had urolithiasis
whereas 4 of 6 (67%) dogs with MAPSS had urolithiasis
In the dog with the closed cEHPSS and long-term urolithiasis
and urethral uroliths (< 1.0 mm) were detected via ultrasound
Additional plain radiographs revealed very small
faint mineralizations (< 1.0 mm) in both kidneys and a mineral opaque structure of 2.6 mm in length at the level of the prostatic part of the urethra
multiple nephroliths had already been reported on ultrasound 1 month before cEHPSS attenuation
At the time of the prospective follow-up visit
the dog had a urinary score of 4 and unremarkable blood and urinalysis
One of the dogs with MAPSS had very small cystoliths preoperatively
which were not removed at the time of cEHPSS attenuation because of their small size
cystoliths (1.0 to 2.0 mm) were still observed
The remaining 3 dogs with MAPSS and long-term urolithiasis developed new uroliths
One dog had ammonium urate cystoliths that were removed at the time of the cEHPSS attenuation and had 60 months prior to the prospective follow-up visit calcium oxalate and struvite cystoliths removed
at the time of the prospective follow-up visit
as well as urethroliths (1.1 mm) were diagnosed by ultrasound
only the cystoliths were radiopaque (3.5 X 2.7 mm)
and urinalysis revealed amorphous crystalluria
The fasting ammonia concentration of that dog was normal
but the obtained sediment was not sufficient to allow quantitative analysis
although it revealed calcium oxalate crystals
only cystoliths had been present initially
and those were removed at the time of cEHPSS attenuation
The dog had a second cystotomy for removal of multiple newly formed ammonium urate cystoliths 15 months after cEHPSS attenuation
At the time of the prospective follow-up visit 16 months after surgery
the dog presented with hyperammonemia and very small mineralizations (< 1 mm) were detected in the left renal pelvis
The last dog had nephroliths (2.5 mm) and cystoliths (1.0 mm) at the time of cEHPSS attenuation that were removed
the nephroliths (< 1.0 mm) were still present
Urinary bladder echoic foci were observed in 5 of 25 (20%) dogs
Three of these dogs had closed cEHPSS and no urolithiasis (one dog had struvite crystalluria
and the last one did not have crystalluria)
Two dogs had MAPSS and concurrent urolithiasis (one dog without crystalluria and the other with amorphous crystalluria)
In 3 of the 4 dogs with closed cEHPSS that presented with nephrolithiasis at time of diagnosis
nephrolithiases were absent at the time of the prospective follow-up visit
echoic foci were visible at the level of the renal pelvis (initial nephrolith was 8.7 X 4.7 X 8.3 mm)
whereas in the other 2 dogs (initial nephroliths were 2.0 and 3.0 mm in one dog and 4.4 and 6.0 mm in the other dog) no echoic foci were observed
The remaining dog with closed cEHPSS and preoperative nephrolithiasis developed postoperative cystolithiasis
Although there was persistent nephrolithiasis
at long-term the nephroliths were smaller compared to before
dogs in cU+ and dogs in cU– had significantly less urolithiasis compared to dogs in pU+/− (P = .013
No statistical significance in urolithiasis was present between dogs of cU+ and cU– (P = 1.000)
Dogs in cU+ had significantly less urolithiasis at the time of the prospective follow-up visit compared to the time of cEHPSS attenuation (P = .001)
whereas no significant difference was present over time in dogs of pU+/− (P = .317)
this was the first study that documented the presence of urolithiasis long-term after surgical attenuation of a cEHPSS in dogs
This study revealed that dogs with closed cEHPSS that had urolithiasis at the time of surgical attenuation did not have a higher risk to have recurrent urolithiasis compared to dogs that did not have urolithiasis at the time of cEHPSS surgery
In the only dog with a confirmed closed cEHPSS and long-term urolithiasis
nonradiopaque cystoliths were detected at long-term follow-up
while the radiopaque nephroliths that were present at the time of cEHPSS diagnosis decreased in size
the nephroliths that were present at the time of surgical attenuation in the other dogs with closed cEHPSS decreased in size or even disappeared over time
half of the dogs that developed MAPSS following surgical attenuation of cEHPSS were diagnosed with uroliths that were either not yet present or in which previous cystoliths had been removed at the time of surgical attenuation of the cEHPSS
it was considered unlikely that the uroliths in that particular dog were composed of ammonium urate
No radiographic examination was performed in the third dog with hyperammonemia that also presented with nonobstructive uroliths
Only 1 of 19 dogs with a confirmed closed cEHPSS in our study was diagnosed with mineral-opaque lithiasis in the kidneys and prostatic urethra and radiolucent cystoliths at the time of the prospective follow-up visit
and uroliths were not removed to determine the urolith composition
In the current study, a urinary scoring system was used to quantify the number of urinary signs. Uroliths that solely contain ammonium urate typically have a smooth surface, which limits irritation to the bladder mucosa3; consequently, dogs with ammonium urate urolithiasis might be asymptomatic. Up to 67% of dogs with cEHPSS are reported to have urinary complaints.6 In our study
32% (6/19) of dogs with cEHPSS had 1 or more urinary complaints between cEHPSS surgery and the prospective follow-up visit
but only 5% (1/19) of dogs with closed cEHPSS had urolithiasis
All dogs that developed MAPSS after cEHPSS surgery were reported to have urinary complaints between the cEHPSS attenuation and the prospective follow-up visit
whereas only 67% (4/6) of dogs presented with long-term urolithiasis
Quantification of urinary signs helps to determine their effect on the quality of life of affected dogs
accurateness of the answers is based on the owners’ memory and observation competence
As the owners of most dogs participated in previous studies
questionnaires about the presence of clinical signs at the time of the cEHPSS diagnosis were already available
ideally a negative control group would have been added to compare the prevalence of urolithiasis long-term in dogs following cEHPSS to those that never had vascular anomalies
dogs with successful cEHPSS closure seemed no longer prone to develop urolithiasis and associated urinary complaints in contrast to dogs that developed MAPSS following cEHPSS surgery
nephroliths (partially) dissolved after successful surgical attenuation of cEHPSS
Supplementary materials are posted online at the journal website: avmajournals.avma.org
No third-party funding or support was received in connection with this study or the writing or publication of the manuscript
The authors wish to thank all dog owners for participating in the study and all referring veterinarians for their help in providing data of the dogs and thereby enabling this study
Osborne CA, Lulich JP, Polzin DJ, et al.; Perspectives from the Minnesota Urolith Center. Analysis of 77,000 canine uroliths. Vet Clin North Am Small Anim Pract. 1999;29(1):17-38, ix-x. doi:10.1016/S0195-5616(99)50002-8
Canine urolithiasis: a look at over 16 000 urolith submissions to the Canadian Veterinary Urolith Centre from February 1998 to April 2003
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WE-S architects have transformed an old 1250-m² warehouse with a gleaming facade of sheet metal into a therapy-dog centre which trains service dogs for people with disabilities
The name of the centre honours the famous Akita dog Hachiko
who still enjoys wide recognition in Japan thanks to his lifelong fidelity to his master
To make the best use of the former agricultural warehouse
the architects have reduced the volume to a pentagonal floor plan
they have opened up the old facade to create roofed-in outdoor training areas
The existing sheet-metal roof serves as a roof surface for the new structure as well
The two-storey dog-training space is at the centre of the building
This area is surrounded by a gallery whose skylights provide a well-lit interior
communal areas and kennels are grouped around the training space
A glazed transition space serves as a lobby and connects the dog-training centre with the adjacent concierge’s house
Architecture: WE-S architectsClient: Hachiko vzw
Enrique Espinosa of Eeestudio and Lys Villalba have used recycled shipping containers to create a colourful school for people and animals alike
Studio Perspektiv have revitalized an old heating plant
transforming the cultural monument for Base4Work – a provider of flexible working spaces – into a coworking centre
At the exhibition centre in České Budějovice
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Logout Gateway to the world of smart farming
Together with two partners from the business community
Fisheries and Food Research (ILVO) in Merelbeke (B.) has converted a New Holland Boomer 45 into an autonomous
The autonomous electric tow tractor Djust-E was officially unveiled on 7 June during the Agri Tech Day 23 at the ILVO site in Merelbeke
The Djust-E experienced its maiden trip last week
“In the meantime he has already worked with a flail mower
with a cultivator and with a rotary harrow
the work went according to plan,” says Simon Cool
engineer at ILVO and responsible for the electrification and automation project
in which mechanization company Verschueren (Lochristi) and electric actuator manufacturer Linak were also involved
According to Cool it is the very first tractor in Flanders that drives both autonomously and is electrically driven
The conversion of the New Holland Boomer 45 took several months
The diesel engine not only provides the drive
but also forms the connection between the front axle and the rear (transmission)
you no longer have a functional machine,” says Verschueren
The mechanization company has built a completely new chassis to accommodate the electric motor
on which the battery pack can be suspended
which can be exchanged quickly and semi-automatically
The battery pack on the front linkage consists of a heavy lead-acid battery of 15 kWh with which you can work on the field for 2 to 3 hours
Cool: “That was sufficient for our testing purposes
you can already increase the range considerably.”
In addition to the electric drive and operation
regulates its linkage and controls implements
ILVO wrote the software for this and integrated the sensors
This project involved intensive collaboration with the Danish supplier of actuators Linak
Objective—To develop a practical ultrasonography-guided injection approach to anesthetic blockade of the femoral nerve in calves and to assess the method's accuracy
Animals—13 cadavers of 4-week-old male Holstein Friesian calves
Procedures—Detailed topographic and anatomic cross-sectional evaluation of the relevant topography in 3 cadavers was performed to identify optimal injection approaches to the femoral nerve
and ileal) were evaluated by simulated ultrasonography-guided perineural injection of methylene blue dye in 10 cadavers
number of needle redirections required for correct needle positioning
and injection success as defined through a 3-point grading system were recorded
Results—The dorsal paravertebral approach yielded the best results
compared with the ileal and ventral paravertebral approaches
to properly and adequately stain the targeted nerve
Conclusions and Clinical Relevance—The dorsal paravertebral injection technique appeared to be the best choice for performing a femoral nerve block in calves
although this technique will need to be further evaluated in live calves to determine its effectiveness and clinical usefulness
Diagnostic perineural anesthesia of the femoral nerve in cattle might be helpful in identifying quadriceps muscle involvement in those with complex spastic paresis
The typical clinical manifestation of spastic paresis in cattle is involuntary spastic contractions of the gastrocnemius muscle when the cattle are standing. In contrast, a variant manifestation in Belgian Blue calves is mainly characterized by quadriceps femoris muscle involvement in spasticity of the hindquarters.1 To the authors’ knowledge
involvement of the quadriceps muscle in spastic paresis in cattle still needs to be confirmed
Spastic paresis of the gastrocnemius muscle or quadriceps muscle in calves is differentiated through the evaluation of posture and gait
Calves with spastic paresis of the gastrocnemius muscle have spastic hyperextension of the affected hind limb in a caudal direction
whereas those in which the quadriceps muscle is affected primarily have cranially directed hyperextension of the limb
a higher than usual incidence of mixed spastic paresis involving both muscles has been observed in Belgian Blue calves
and probably other muscle groups of the hind limb causes repetitive hyperextension of the affected limb
this hyperextension is variably directed cranially
Standard treatment for spastic paresis includes tenectomy or surgical denervation (partial neurectomy of the tibial nerve2,3) of the gastrocnemius muscle bellies; however
no treatment has been described for mixed spastic paresis
Partial tibial neurectomy to denervate the gastrocnemius muscle is contraindicated when the quadriceps muscle is a major contributor to the spasticity
The overactivity of quadriceps and gastrocnemius muscles can keep the affected limb in a neutral
When the influence of a contributing muscle is removed
as would occur with partial neurectomy of the gastrocnemius muscle
spastic contractions originating from the other contributing muscles become dominant and possibly exaggerated
This situation can cause an inability to remain standing
When the gastrocnemius muscle is the primary contributor to the spasticity
surgical intervention can ameliorate pain and improve growth in an affected calf; however
a calf with mixed spastic paresis will continue having spastic contractions
The purpose of the study reported here was to explore various approaches for a practical ultrasonography-guided injection of the femoral nerve in calves
and to identify the superior technique so that it might be evaluated further in live cattle
the topographic anatomy of the femoral nerve was evaluated in the cadavers of 2 calves (a 78-kg Belgian Blue calf [age
and the cross-sectional anatomy was evaluated in an additional Holstein calf (50 kg; age
All calves had been euthanized for reasons unrelated to any pathological changes involving their neuromusculoskeletal structures
ultrasonography-guided approaches to injection of the femoral nerve were evaluated in the cadavers of 10 healthy 4-week-old male Holstein-Friesian calves with a median body weight of 50 kg (range
These calves had been used in unrelated toxicological studies that required euthanasia
The protocol for both phases of the present study was approved by the Ethical Committee for Animal Research of Ghent (EC No
Topographic and cross-sectional anatomic evaluation of the femoral nerve—Topographic anatomy of the femoral nerve was reviewed with the aid of anatomy textbooks.13,14 Dissection of the 2 calf cadavers was performed within 4 hours after euthanasia
the cadavers were positioned in dorsal recumbency for dissection of the medial thigh and inguinal region
the calves were positioned in lateral recumbency for dissection of the lumbosacral region and the hindquarter musculature
Anatomic landmarks relevant for ultrasonography of the regions of interest were recorded
and possible approaches for needle insertion were identified
Ultrasonography-guided injection of the femoral nerve—This portion of the study was performed immediately after calves were euthanized
All procedures were performed by the same operator (CDV)
who had limited experience with ultrasonography-guided injections
Each cadaver was positioned in lateral recumbency to mimic the clinical situation for anesthetic nerve blockade
The skin overlying the predetermined injection sites was clipped of hair and washed
Relevant anatomic landmarks were first identified by means of ultrasonography
the spinal and hindquarter musculature was dissected to expose the femoral nerve and verify the accuracy of dye deposition around the nerve
Forty injections were performed in 10 cadavers
including 10 via the ventral paravertebral approach
Figure 1—Diagram of the ventral view of the lumbosacral neural plexus in a calf cadaver
showing the femoral nerve zones targeted for ultrasonography-guided perineural injection of methylene blue dye: dorsal approach (red circle)
Citation: American Journal of Veterinary Research 74, 5; 10.2460/ajvr.74.5.750
Several variables were recorded to assess the outcome of each injection technique
Ultrasonographic image quality was scored as follows: 1 = excellent (landmarks clearly identified as 2 hyperechogenic lines [ventral paravertebral approach and dorsal paravertebral approach] or as 2 hypoechogenic spots [ileal approach]; needle clearly identified as a continuous hyperechogenic line); 2 = acceptable (landmarks or needle but not both poorly identified); 3 = poor (both landmarks and needle poorly identified)
it was slightly withdrawn and reinserted at a corrected angle
which was defined as a repositioning attempt
The deposition of the dye in relation to the femoral nerve was scored on a 3-point scale
An injection score of 1 was given when the nerve was stained (epineural) or 2 when the nerve was not stained but dye was found in the perineural tissues
< 5 mm away from the femoral nerve (perineural)
When dye was found > 5 mm away from the femoral nerve
an injection score of 3 was given (peripheral)
Injection was considered successful when the nerve was stained (injection score 1)
Statistical analysis—Statistical and graphic analyses were performed with statistical software.f,g The Kendall τ nonparametric correlation coefficient was calculated to correlate ultrasonographic image and dye injection scores
Statistical differences in both types of scores between the 3 ultrasonography-guided techniques (ventral paravertebral approach
and ileal approach) were evaluated via the Kruskal-Wallis test
The Jonckheere-Terpstra test was used to evaluate whether a trend existed in the scores obtained after injection and to test the hypothesis that a learning effect existed for the injection techniques (ie
better injection scores for femoral nerves injected at the end of the experiment)
A value of P < 0.05 was considered significant for all analyses
Topographic and cross-sectional anatomy of the femoral nerve—The femoral nerve was found to originate from several branches at L4 through L6. These branches were surrounded by connective tissue and located near the vertebral bodies of L5 and L6, ventral to the transverse processes of these vertebrae and medial to the psoas major muscle (Figures 2 and 3)
the nerve continued ventrally in a caudoventral direction
toward the wing of the sacrum (ala ossis sacri) and medial to the shaft of the ileum
and passed between the tendon of the psoas minor and iliopsoas muscles
where it was accompanied by the external iliac artery and vein
the femoral nerve branched off the saphenous nerve
which turned medially and spread sensory branches to the skin of the medial thigh and distally to the level of the tarsus
It also contained motor branches for several adductor muscles of the hind limb (sartorius
where it was accompanied by the cranial femoral artery and vein
The nerve split into several branches to innervate the various parts of the quadriceps femoris muscle
Figure 2—Photograph showing a lateral view of the dissected lumbosacral area that reveals the origin of the femoral nerve in a calf cadaver
Figure 3—Photograph showing a cranial view of a lumbosacral transverse section at the level of L6 in a calf cadaver
The solid black line indicates the femoral nerve
When the cadaver was positioned in dorsal recumbency
the nerve was located deep in the inguinal region
surrounded by several important blood vessels
which might become damaged when an inguinal approach is used
3 possible routes to reach the femoral nerve by injection were proposed for study: 2 targeting the nerve near its origin in the paravertebral area (dorsal and ventral paravertebral approach) and 1 aimed at the mid–ileal shaft region (ileal approach)
Once the needle tip reached a position < 1 cm lateral to the vertebral body of L6
it was further advanced for a maximum 1 cm under the transverse process
Figure 4—Photograph (A) of the dorsal aspect of the lumbosacral area of a calf cadaver in left lateral recumbency and ultrasonographic image (B) showing the position of the needle used for a dorsal paravertebral approach to injection of the femoral nerve in a calf cadaver
left is the rump of the calf and right is the hindquarter
The straight dotted line indicates the spinal axis of the calf
and the circular dotted line indicates the tuber coxa
arrowheads indicate the needle near the cranial border of the transverse process of L6; the straight white line indicates the location of the needle
a = Transverse process of the fifth lumbar vertebra
b = Transverse process of the sixth lumbar vertebra
As soon as the needle was identified in this region
it was oriented toward the contralateral tuber ischiadicum
the needle could be followed ultrasonographically until it reached the cranial border of the transverse process of L6
Further insertion made the needle disappear beneath the transverse process until it touched the body of L6
the needle was withdrawn a few millimeters
Figure 5—Photograph of the dorsal view of the lumbosacral area of a calf cadaver in left lateral recumbency showing the position of the needle used for a ventral paravertebral approach to injection of the femoral nerve. The transducer was used to identify the intertransverse process space between L5 and L6. The straight solid line indicates the lateral edge of the horizontal plane of the lumbar transverse processes. See Figure 4 for remainder of key
The spinal needle was inserted cranial to the transducer and oriented toward the blood vessels
Once the tip of the needle was identified near this location
Figure 6—Photograph (A) of the lateral view of the gluteal region of a calf cadaver in left lateral recumbency and ultrasonographic image (B) showing the position of the needle used for an ileal approach to injection of the femoral nerve in a calf cadaver
the location of the tuber coxa (dashed line)
and right femorotibial joint of the calf (rectangle) are indicated
the femoral artery and vein were used as landmarks as indicated (rectangle)
Notice the needle near the neurovascular vessels (arrows)
Simulated anesthetic blockade of the femoral nerve—A significant (P < 0.05) correlation was identified between the injection score and ultrasonographic image score for the ventral paravertebral approach (τ = 0.66) and the ileal approach (τ = 0.62) but not for the dorsal paravertebral approach (τ = 0.40; Figure 7)
The median number of times the needle required repositioning in the dorsal approach was 5 (range
Figure 7—Correlation between injection score and ultrasonographic image quality score for dorsal paravertebral (black)
and ileal (red) approaches to ultrasonography-guided injection of the femoral nerve in calf cadavers (n = 10)
Image quality was scored as follows: 1 = excellent
Injection scoring was performed as follows: 1 = epineural
The femoral nerve was stained in 8 of 10 performances of dorsal paravertebral approach
in 5 of 10 for the ventral paravertebral approach
The proportion of injections that achieved an injection score of 1 was highest in the dorsal paravertebral approach
these proportions were not significantly (P = 0.53) different
No significant differences in injection scores (P = 0.13) nor in ultrasonography scores (P = 0.65) were observed among the approaches
Although the injection scores improved the more injections were performed for each approach
this trend was not significant (P > 0.10)
This preliminary cadaver study showed that simulated ultrasonography-guided injection of a dye adjacent to the femoral nerve in calves is possible
The success rates of the 3 techniques could be considered equally efficient for performance of femoral nerve block in cadavers
which is important for correct needle positioning when the injection target is specific or deeply located anatomic areas or structures
This characteristic is of major importance in well-muscled beef cattle
in which bony landmarks are not as readily palpable as they are in thinner breeds
Holstein calves were used in the present study mainly because of economic considerations and availability
Their body conformation facilitated the application of the approaches by a moderately experienced operator
In humans and dogs, a femoral nerve block is performed through a medial, inguinal region approach.10,11,17 The topographic and cross-sectional anatomic evaluation in the present study showed that an inguinal approach to nerve injection was highly impractical
mainly because of the large muscle volume often encountered in beef calves and the high risk of inadvertent blood vessel damage
Clinical application of this approach would also require deep sedation of a calf to allow a safe approach
followed by sedative reversal for subsequent gait evaluation
which would further complicate the procedure
Lateral approaches were deemed more efficient than an inguinal approach because of the more superficial location of the femoral nerve and the proximity of specific anatomic landmarks such as the transverse processes of certain lumbar vertebrae
and important adjacent vascular structures
the femoral nerve was not directly visible because of the nerve's location close to the lumbar bony vertebral column
the needle tip could be accurately advanced to the cranial border of the transverse process of L6
ultrasonography was only useful to identify the correct position for needle insertion
Further insertion was performed without the needle tip visible and guided by external characteristics such as the contralateral tuber ischiadicum
This complication might explain the lower success rate associated with the ventral technique
The ventral paravertebral approach targets a slightly more caudal area of the femoral nerve than does the dorsal paravertebral approach
which might overlap with the origin of the obturator nerve in some calves
Deposition of local anesthetic in this region could cause paralysis of quadriceps and adductor muscles
which might complicate clinical evaluation of the nerve block
the least amount of anesthetic should be used when the ventral approach is used
The main difficulty encountered with the ileal approach was the correct identification of the cranial femoral artery and vein
these vascular structures were not clearly outlined on the ultrasonographic images
mainly because of the absence of blood flow in the cadavers
which precluded the use of Doppler techniques to enhance their detection
The inability to clearly see these landmarks in cadavers may have contributed to a lower image quality score for the ileal versus other approaches
Use of the ileal approach in live calves might provide better visibility of the landmarks and therefore better results than those obtained in this cadaver study
the ileal approach enabled nerve identification and allowed needle guidance to the perineural level
injection of a dye solution could be seen as it spread along the neural and vascular structures
A disadvantage to use of the ileal approach with Doppler techniques is that it would require more sophisticated equipment
increasing the financial burden of the procedure
We considered the dorsal paravertebral approach to be the most user-friendly of the 3 techniques evaluated and believe that moderate experience in ultrasonography would be sufficient to obtain a high success rate for staining the targeted nerve
and the portion of the injection path that could not be seen was small
the small number of calves used is a limitation to the study
Clinical application of these ultrasonographic approaches in healthy cattle would be essential for confirming the suitability of the described injection techniques
the potential of the dorsal paravertebral technique to enable identification of quadriceps muscle involvement in the spastic paresis syndrome warrants further investigation
R, version 2.14.0, R Foundation for Statistical Computing, Vienna, Austria. Available at: www.r-project.org/
La parésie spastique du quadriceps fémoral: une nouvelle entité clinique chez le veau de race Blanc Bleu Belge
Chirurgische behandeling van spastische parese bij het rund door denervatie van de m
Anatomie du muscle gastrocnémien des bovins appliquée à la cure chirurgicale de la parésie spastique
Interest of anesthetic blocs for assessment of the spastic patient
Evaluation and management of spastic gait in patients with traumatic brain injury
Interest of peripheral anesthetic blocks as a diagnosis and prognosis tool in patients with spastic equinus foot: a clinical and electrophysiological study of the effects of block of nerve branches to the triceps surae muscle
Spasticité: intérět du testing par anesthésie locorégionale et blocs thérapeutiques
Peripheral neurolytic blocks and spasticity
Diagnosis and management of lameness in the horse
Ultrasound-guided approach for axillary brachial plexus
Ultrasound-guided block of the sciatic and femoral nerves in dogs: a descriptive study
Ventral ultrasound-guided suprainguinal approach to block the femoral nerve in the dog
Color atlas of veterinary anatomy: the ruminants
Peripheral nerves: ultrasound-guided interventional procedures
Semin Musculoskelet Radiol 2010; 14:559–566
Ultrasound imaging for regional anesthesia in infants
children and adolescents: a review of current literature and its application in the practice of extremity and trunk blocks
Anatomical and experimental studies of brachial plexus
and femoral nerve-location using peripheral nerve stimulation in the dog
To quantify the degree of dural compression and assess the association between site and direction of compression and articular process (AP) size and degree of dural compression with CT myelography
Spinal cord-to-dura and AP-to-cross-sectional area of the C6 body ratios (APBRs) were calculated for each noncompressive site and site that had > 50% compression of the subarachnoid space
Site of maximum compression had the largest spinal cord-to-dura ratio
Fisher exact test and linear regression analyses were used to assess the association between site and direction of compression and mean or maximum APBR and spinal cord-todura ratio
Mean ± SD spinal cord-to-dura ratio was 0.31 ± 0.044 (range
0.20 to 0.41) for noncompressive sites and 0.44 ± 0.078 (0.29 to 0.60) for sites of maximum compression
Sites of maximum compression were intervertebral and extra-dural
Thirteen horses had dorsolateral and lateral compression at the AP joints
secondary to AP (n = 7) or soft tissue proliferation (6)
Site significantly affected direction of compression
and directions of compression from occiput through C4 were primarily ventral and lateral
whereas from C6 through T1 were primarily dorsal and dorsolateral
No linear relationship was identified between mean or maximum APBR and spinal cord-to-dura ratio
CT myelography may be useful for examination of horses with suspected cervical compressive myelopathy
Degree of compression can be assessed quantitatively
and site of compression significantly affected direction of compression
objective quantification of the degree of spinal cord compression
or associations between the location and direction of compression or between the size of an AP and degree of compression
the objectives of the retrospective study reported here were to characterize CTM findings of the cervical spine in ataxic horses
quantify the degree of dural compression (ratio of the cross-sectional area of the cervical spinal cord and the total cross-sectional area of the subarachnoid space plus the cervical spinal cord)
and determine whether associations existed between the location and direction of the compression or between the size of the APs and the degree of compression
The hypotheses were that associations existed between the location and direction of the compression and between the size of the APs and the degree of compression
All horses with ataxia of all limbs that underwent CTM of the cervical spine between January 2015 and January 2017 were eligible for inclusion in this retrospective study. Age, body weight, breed, sex, degree of ataxia, and CTM findings were retrieved from the medical records. Physical examination was performed by one of the authors (EA or TM). A scale of 0 to 5 was used to grade the severity of ataxia.15
Non–contrast-enhanced CT images were acquired before CTM images were acquired
Horses were anesthetized and positioned in right lateral recumbency
for image acquisition with a standard-bore (diameter
The CT machine had a limited amount of hardware between a horse's shoulders and the bore
which made acquisition of images of the caudal region of the cervical spine possible
The scanning parameters were as follows: 135 kVp
The bone or soft tissue filter was applied
and images were acquired from the occiput through T1
Two scans were necessary to image the entire cervical spine: one from the occiput through C3 and another from C3 through T1
For CTM image acquisition, the subarachnoid space was punctured at the atlanto-occipital joint, 50 mL of CSF was removed, and 30 mg of iodine/ kg of iohexol (300 mg of iodine/mL) was injected with an aseptic technique and ultrasound guidance.16 To increase the caudal movement of iohexol
the horse's head was elevated for 5 minutes after injection but prior to image acquisition
A board-certified equine radiologist (TR) who was blinded to patient history
and prior CTM reports retrospectively reviewed CTM images on a dedicated workstation with a DICOM viewer (Osirix; Pixmeo SAR)
and dorsal planar images were made by use of multiplanar reconstruction
Evaluation of dural compression and all measurements were made from the transverse plane of the multiplanar reconstruction (plane perpendicular to the spinal cord
whereas the sagittal plane of the multiplanar reconstruction was the plane parallel to the vertebral spinous process)
a noncompressive site was defined as a site that did not have narrowing or had only mild flattening of the subarachnoid space
All sites with > 50% compression of the subarachnoid space (when compared with noncompressive sites in the local region cranial or caudal to the site of dural compression) were recorded independent of the direction of the compression
the anatomical structure that caused narrowing of the contrast column)
or intradural intramedullary) of narrowing of the subarachnoid space were noted
Deviation of the spinal cord and presence of a modification in the shape of the spinal cord were assessed subjectively (when compared with noncompressive sites in the local region cranial or caudal to the site of dural compression)
If > 1 direction of subarachnoid space compression was present at each site
the direction that caused the most compression was recorded
the site with the maximum spinal cord-to-dura ratio was considered to be the site of maximum dural compression
A ratio, denoted as AP-to-vertebral body ratio (APBR), was derived to assess the size of the AP; the ratio was the cross-sectional area of the AP and the cross-sectional area of the largest part of the cranial aspect of the body of C6.14 The ratio was calculated for all horses at all sites from C2 through T1 that had > 50% compression of the subarachnoid space
At all sites that had > 50% compression of the subarachnoid space
linear regression analyses were performed to assess the effect of the size of the AP (determined with use of the APBR) on the degree of subarachnoid space compression
A linear regression model with spinal cord-to-dura ratio as the dependent variable and APBR (mean or maximum value between both sides at 1 location) as the independent variable was fitted
with slope as the summary statistic and the P value indicating whether the slope differs from zero
Additionally for the same sites with > 50% compression
the Fisher exact test was used to assess the effect of the site on the direction of the compression of the subarachnoid space (dorsal
the cervical spine was divided into 3 parts: occiput through mid-C4
All statistical analyses were performed with commercially available software (R version 3.6.3; R Foundation)
Values of P < 0.05 were considered significant
Twenty-six horses met eligibility requirements and were included in the study
All horses were warm-blood horses and located in Europe; no horse had a history of travel outside Europe
and body weight ranged from 173 to 632 kg (mean
Duration of clinical signs was variable (1 week to several years)
Three horses had an episode of signs of severe neck pain
manifested by an inability to move their necks and the presence of neck ventroflexion
all horses had signs of ataxia for all limbs; median grade of ataxia was 3 (range
Images were acquired through CTM for all horses from the occiput through T1
and all horses had at least 1 site with > 50% compression of the subarachnoid space
A ratio could be calculated for all horses at all available noncompressive sites and sites with > 50% compression (Table 1)
0.40 ± 0.076 (0.28 to 0.60) for sites with > 50% compression of the subarachnoid space
and 0.44 ± 0.078 (0.29 to 0.60) for sites with maximum dural compression
Spinal cord-to-dura ratios from C2 through T1 determined with CT myelography (CTM) between January 2015 and January 2017 for 26 client-owned warmblood horses with ataxia that affected all limbs
Note that the spinal cord-to-dura ratios for the site of maximum compression† for horses 4
and 13 was comparable to the ratios for the noncompressive sites
Findings of CTM for these 4 horses were considered unremarkable
*Indicates site had > 50% compression of the subarachnoid space but was not the site of maximum compression
†Indicates site of maximum compression of the subarachnoid space
Dorsal compression of the subarachnoid space was caused by direct impingement by the cranial aspect of the dorsal arch (5/7 sites) or impingement by soft tissue–attenuating material cranial or ventral to the cranial aspect of the dorsal arch (2/7 sites)
Age and sex (F, mare; M, stallion; MC, gelding) and, identified with CTM, site, direction of the compression, compressing structure, spinal cord-to-dura ratio, and spinal cord shape (A, abnormal; N, normal) at the sites of maximum dural compression, defined as the site with the largest spinal cord-to-dura ratio, for each horse of Table 1
Figure 1Images acquired with CT myelography (CTM; in bone window) of sites of ventral dural compression for 2 horses
A—Midsagittal reconstructed image of C4 through C6 for horse 17
In comparison with the other intervertebral disks
note dorsal protrusion of the C4-5 disk and subsequent ventral dural compression (black arrowhead)
Also note gas attenuation in the C4-5 and C6-7 disks (white arrowheads)
B—Midsagittal reconstructed image of C5 through C7 for horse 23
Note severe decreased thickness of the intervertebral symphysis of C6 through C7
dorsal protrusion of the C6-7 disk (black arrowhead)
and subsequent ventral dural compression and dorsal deviation of the spinal cord (asterisk) as well as severe increased attenuation of the cranial one-half of the body of C7 (white arrowheads) with new bone formation ventrally (arrow)
C—Transverse image of C6 through C7 of the same horse in panel B
Ventral dural compression is more severe on the left side (white arrowhead)
a feature that is not conspicuous in panel B and may be missed with radiographic myelography
Also note dorsoventral flattening of the spinal cord
lysis of the right and cranial aspects of the body of C7 (black arrowhead)
and new bone formation of the right and caudal aspects of the body of C6 (black arrows)
These abnormalities are compatible with previous trauma or infection
Citation: Journal of the American Veterinary Medical Association 259, 10; 10.2460/javma.20.11.0614
Figure 2Images acquired with CTM (in bone window) of sites of lateral dural compression for 3 horses
Note bilateral compression caused by both articular processes (APs; arrowheads) and abnormal round shape and increased height of the spinal cord
Note bilateral compression caused by both APs (arrowheads) and the abnormal triangle shape of the spinal cord
C—Transverse image of the atlanto-occipital joint for horse 3
Note lateral compression of the dura by the right occipital condyle (O; arrowhead)
which was considered to be an incidental finding because it was seen on only the right (gravity-dependent) side (each horse was positioned in right lateral recumbency for CTM)
Also note leakage of contrast material in the epidural space dorsally (asterisk)
Figure 3Images acquired with CTM (in bone window) of sites of dorsolateral dural compression
leading to dorsolateral compression (arrowhead)
and are fragmented and have irregularities of the subchondral bone (not clearly visible on this image)
Also note the leakage of contrast material in the epidural space (arrow)
The left and right APs are large and round
dorsolateral compression (arrowhead) is noted owing to soft tissue–attenuating material between the left AP and the dural tube
and proliferated soft tissue (white arrowheads) is causing dorsolateral dural compression (black arrowhead)
The epidural fat is conspicuous on the dorsal right side (arrow) but not the left side
most likely because of a mass effect from the soft tissue proliferation
Also note pooling of the contrast material on the right (asterisk)
most likely because the right side was the gravity-dependent side (each horse was positioned in right lateral recumbency for CTM)
Figure 4Images acquired with CTM (in bone window) of the site of maximum dural compression for horse 2
A—Midsagittal reconstructed image of C4 through C6
Note new bone formation of the cranioventral aspect of the dorsal arch of C6 (arrow) that created dorsal extradural compression of the subarachnoid space
Also note the ill-defined fragmentation of the spinous process of C6 (black arrowhead) surrounded by severe increased attenuation of the bone (white arrowheads)
Note the cranial tip of new bone formation (black arrow) of the cranial dorsal arch of C6 and soft tissue proliferation to the left of this new bone formation (white arrow) that created more severe dorsal compression (vs that seen in panel A) at this level
Changes seen in panel B are not seen in panel A and may be missed with a radiographic myelography
which assesses compression mostly in the midsagittal plane
Dorsal compression was caused by direct impingement by the cranial aspect of the dorsal arch
In 13 of the 51 sites that had > 50% compression of the subarachnoid space, the shape of the spinal cord was considered abnormal in the transverse plane (Figures 3 and 4)
with 12 identified at the site of maximum dural compression
Compression was dorsolateral at 6 of the 13 sites
Eight of the 13 sites had a dorsal deviation of the spinal cord and ventral compression
with 7 of 8 identified at the site of maximum dural compression
In 4 horses (horses 4, 7, 11, and 13; Tables 1 and 2)
the degree of maximum compression was considered mild
0.29 to 0.30) that were comparable to the ratios for noncompressive sites
and dorsal deviation or abnormal shape of the spinal cord was not evident
clinically relevant static compression was considered unlikely
and the CTM findings were considered unremarkable
The site of maximum compression was identified at C2 through C4
The direction of dural compression of all sites with > 50% of compression of the subarachnoid space was detailed (Table 3)
The directions from the occiput through C4 were primarily ventral and lateral
whereas directions from C6 through T1 were primarily dorsal and dorsolateral
These differences were significant (P < 0.001)
Direction of compression of the sites that had > 50% compression of the subarachnoid space as identified with CTM for the horses of Table 1
0.48 to 2.4) for all sites that had compression of the subarachnoid space and 1.0 ± 0.24 (0.48 to 2.4) for all sites that did not have compression of the subarachnoid space
The 4 sites of compression identified at the occipital condyle were excluded from the analysis because calculation of the APBR at this location was not possible
Determined with linear regression analyses
mean (P = 0.5) or maximum (P = 0.6) APBR did not have a significant effect on the degree of dural compression
The retrospective study reported here revealed that CTM of the cervical spine of ataxic horses was able to help identify the structure that caused dural compression and the direction of maximum compression
but an association was detected only for the former
Lateral and dorsolateral compression may be overlooked with radiographic myelography
which mostly detects dorsoventral compression because laterolateral views are usually obtained
whereas oblique views are difficult to obtain and assess
a cutoff value for the ratio that distinguished between compressive and noncompressive sites could not be determined because of the lack of postmortem examinations
Trauma was also suspected as the cause of fissure in horse 2
the present study revealed the CTM findings of ataxic horses
Computed tomographic myelography was useful to identify the cause of dural compression
the degree of static compression was considered unlikely to explain the clinical signs
Further studies are necessary to correlate CTM findings with histologic findings and to identify objective and reliable CTM decision criteria to differentiate horses with CCM from those without CCM
No external funding was used in this study
The authors declare that there were no conflicts of interest
Taylor and Houdellier for their contributions to this study
Lesions of the equine neck resulting in lameness or poor performance
Current dorsal myelographic column and dural diameter reduction rules do not apply at the cervicothoracic junction in horses
Assessment of the utility of using intra- and intervertebral minimum sagittal diameter ratios in the diagnosis of cervical vertebral malformation in horses
Evaluation of decision criteria for detection of spinal cord compression based on cervical myelography in horses: 38 cases (1981–2001)
Comparison of magnetic resonance imaging with standing cervical radio-graphs for evaluation of vertebral canal stenosis in equine cervical stenotic myelopathy
Pathology of the vertebral column of horses with cervical static stenosis
Computed tomography myelographic findings in dogs with cervical spondylomyelopathy
Magnetic resonance imaging features of cervical stenotic myelopathy in 21 dogs
Quantitative evaluation of cervical cord compression by computed tomographic myelography in Thoroughbred foals
Computed tomography and myelography of the equine cervical spine: 180 cases (2013–2018)
Computed tomographic cervical myelography in horses: technique and findings in 51 clinical cases
Computed tomographic examination of the articular process joints of the cervical spine in warmblood horses: 86 cases (2015–2017)
Ultra-sound-guided atlanto-occipital puncture for myelography in the horse
Confirmed and presumptive cervical vertebral compressive myelopathy in older horses: a retrospective study (1992–2004)
and age with cervical vertebral compressive myelopathy in horses: 811 cases (1974–2007)
Radiographic retrospective study of the caudal cervical articular process joints in the horse
Surgical treatment of cervical stenotic myelopathy in horses: 73 cases (1983–1992)
Cervical vertebral lesions in equine stenotic myelopathy
Cervical vertebral compressive myelopathy: diagnosis
Clinical symptoms of patients with intervertebral vacuum phenomenon
State-of-the-art diagnostic methods to diagnose equine spinal disorders
with special reference to transcranial magnetic stimulation and transcranial electrical stimulation
Objective—To determine the spectrum and frequency of abnormalities for low-field magnetic resonance imaging (MRI) examinations of clinically normal Doberman Pinschers and Foxhounds
Animals—37 clinically normal dogs (20 Doberman Pinschers and 17 Foxhounds)
and transverse T1- and T2-weighted images) was performed
Variables assessed were intervertebral disk degeneration
compression of the dorsal portion of the spinal cord
and changes in intraparenchymal signal intensity
Associations between these variables and age
and location of the assessed intervertebral disk spaces were evaluated
Results—Severe MRI abnormalities were detected in 17 dogs
including complete disk degeneration (n = 4 dogs)
Vertebral body abnormalities were detected in 8 dogs
and hyperintense signal intensity was detected in 2 dogs
Severity of disk degeneration and disk-associated compression was significantly associated with increased age
There was a significant association between disk degeneration
and compression of the dorsal aspect of the spinal cord and location of the assessed intervertebral disk space
with the intervertebral disk spaces in the caudal portion of the cervical region being more severely affected
Conclusions and Clinical Relevance—Abnormalities were commonly seen on MRI examinations of the caudal portion of the cervical vertebral column and spinal cord of clinically normal Doberman Pinchers and Foxhounds
Such lesions were probably part of the typical spinal cord degeneration associated with the aging process of dogs
little is known about the clinical relevancy
and prognosis for these cervical spinal cord compressions that do not cause clinical signs and whether they would justify meticulous clinical and MRI monitoring or even early surgical decompression before clinical manifestation of a neurologic deficit
To determine the importance of abnormalities detected during MRI examinations
the spectrum and frequency of structural abnormalities that may not cause problems must be considered
little is known about this subject in veterinary medicine
the low-field MRI features of the cervical vertebral column and spinal cord
with special emphasis on the caudal portion of the cervical region
of clinically normal Doberman Pinschers and Foxhounds were investigated
It was hypothesized that structural abnormalities existed in a substantial portion of the study population and that breed
and sex could influence the development and severity of these findings
it was hypothesized that the development of certain abnormalities could be associated with the location of the assessed intervertebral disk space
This study was part of a larger investigation of the diagnosis and treatment of disk-associated wobbler syndrome in dogs
Animals—Two groups that comprised 37 clinically normal dogs were prospectively evaluated. One group consisted of 20 client-owned Doberman Pinschers. This breed was selected for inclusion because of their predisposition for neurologic syndromes that affect the caudal portion of the cervical vertebral canal and spinal cord.16 The other group consisted of 17 Foxhounds (13 were client-owned dogs and 4 were laboratory-owned dogs)
This breed was selected for inclusion because their conformation and amount of activity are comparable to those of Doberman Pinschers and the fact that this breed is not predisposed to neurologic syndromes that affect the caudal portion of the cervical vertebral canal and spinal cord
Written owner consent was obtained prior to enrollment of client-owned dogs in the study
The study was conducted in accordance with the guidelines of the Animal Care Committee of the University of Ghent
The dogs were defined as clinically normal on the basis of history and results of physical and neurologic examinations
All Doberman Pinschers underwent an additional echocardiographic examination and standardized testing to determine mucosal bleeding time
Dogs were assigned to 2 age categories: dogs ≥ 5 years old (10 Doberman Pinschers and 8 Foxhounds) and dogs ≥ 5 years old (10 Doberman Pinschers and 9 Foxhounds)
Sex distribution was equal between the groups of dogs
All owners were contacted at the end of the study and encouraged to have another physical and neurologic examination performed on their dogs
MRI procedures—A permanent, 0.2-T magneta was used to perform MRI in all dogs
Dogs were positioned in dorsal recumbency with the head and neck extended
The forelimbs were positioned parallel to the thorax
The cervical vertebral column was positioned in a joint coil (circular transmit-receive coil) with an inner diameter of 19 cm
T1 and T2 spin echo–weighted images were obtained for all dogs in sagittal
Images for the transverse plane were aligned perpendicular to the cervical vertebral column
Images of the spinal cord were obtained from C2 through C7 in the sagittal and dorsal planes and from C4 through C7 in the transverse plane
the field of view was 29 cm for the sagittal plane
The T1-weighted sagittal images were obtained with a TR of 700 milliseconds and a TE of 25 milliseconds
The T2-weighted sagittal images were obtained with a TR of 2,700 milliseconds and a TE of 125 milliseconds
Dorsal images were obtained for the T1-weighted sequence with a TR of 600 milliseconds and TE of 25 milliseconds
whereas dorsal images for the T2-weighted sequence were obtained with a TR of 3,900 milliseconds and a TE of 120 milliseconds
Transverse T1-weighted images were obtained with a TR of 1,100 milliseconds and a TE of 25 milliseconds
and the T2-weighted transverse images were obtained with a TR of 5,000 milliseconds and a TE of 120 milliseconds
Slice thickness was 4 mm for the sagittal and dorsal planes and 3 mm for the transverse plane
with no interslice gap for any of the sequences
All images were reviewed separately by 2 investigators (SDD and IMVLG)
and a consensus interpretation was reached
Because disk degeneration is associated with a decrease in signal intensity on T2-weighted images, assessment of intervertebral disk degeneration was based on the signal intensity of each intervertebral disk on midsagittal T2-weighted images (Figure 1)
A non-degenerated disk (score 0) had a homogenous hyperintense signal
a disk with partial disk degeneration (score 1) had heterogeneous loss of the hyperintense signal
and a disk with complete disk degeneration (score 2) had complete loss of the hyperintense signal
Figure 1—Sagittal T2-weighted image obtained during MRI of the caudal portion of the cervical vertebrae of a clinically normal Doberman Pinscher
Disk degeneration is graded as no disk degeneration (score 0; disk space to the left)
partial disk degeneration (score 1; disk space in the middle)
and complete disk degeneration (score 2; disk space to the right)
Each of these intervertebral disks is causing partial compression of the ventral portion of the subarachnoid space (score 1)
Complete compression of the dorsal portion of the subarachnoid space (score 2) is indicated (arrow)
Citation: American Journal of Veterinary Research 71, 4; 10.2460/ajvr.71.4.428
Disk-associated compression of the spinal cord (compression of the ventral aspect of the spinal cord) was assessed on the midsagittal images and, when available, confirmed on the transverse (C4 through C7) T2-weighted images (Figures 2 and 3)
Disk-associated compression was classified as follows: score 0
partial compression of the ventral portion of the subarachnoid space; score 2
complete compression of the ventral portion of the subarachnoid space without compression of the spinal cord; and score 3
compression of the spinal cord with deviation or distortion of the spinal cord
Compression of the dorsal portion of the spinal cord was evaluated on the same images and with the same classification scheme as used for assessment of disk-associated compression of the spinal cord
Figure 2—Sagittal T2-weighted image obtained during MRI of the caudal portion of the cervical vertebrae of a clinically normal Doberman Pinscher
disk-associated compression was classified as partial compression of the ventral portion of the subarachnoid space (score 1 [thick arrow])
complete compression of the ventral portion of the subarachnoid space (score 2 [arrowhead])
and compression of the spinal cord (score 3 [thin arrow])
Figure 3—Transverse T2-weighted image obtained during MRI of the caudal portion of the cervical vertebrae of a clinically normal Doberman Pinscher
Disk-associated compression of the spinal cord is characterized by deviation or distortion of the spinal cord (arrow)
Figure 4—Sagittal T1-weighted image obtained during MRI of the caudal portion of the cervical vertebrae of a clinically normal Doberman Pinscher
Vertebral body abnormalities are characterized as a flattening of the cranioventral border of the vertebral body (arrow)
and sex on severity and the sum of scores for the assessed intervertebral disk spaces were evaluated by use of the Wilcoxon rank sum test
Associations between severity of the assessed variable and location of the assessed intervertebral disk space were tested in 2 ways
the Friedman test (with dog as a block factor) was used
the Page test was used to determine whether severity increased with the more caudally located intervertebral disk spaces
The effect of age category on the location of the assessed abnormality was evaluated by use of the Wilcoxon rank sum test
To evaluate the correlation between the assessed variables
Kendall correlation coefficients were determined
Significance was established at a value of P < 0.05
Animals—Clinically normal dogs (20 Doberman Pinschers and 17 Foxhounds) were included in the study
The group of 10 Doberman Pinschers < 5 years old consisted of 6 males and 4 females that were between 1.5 and 4.7 years old (mean
1.8 years) and weighed between 30 and 46 kg (mean
The group of 8 Foxhounds < 5 years old consisted of 4 males and 4 females that were between 1.5 and 4 years old (mean
1.9 years) and weighed between 27 and 34 kg (mean
The group of 10 Doberman Pinschers ≥ 5 years old consisted of 5 males and 5 females that were between 5.3 and 8 years old (mean
6.2 years) and weighed between 30 and 46 kg (mean
The group of 9 Foxhounds ≥ 5 years old consisted of 5 males and 4 females that were between 5 and 12 years old (mean
6 years) and weighed between 28 and 38.6 kg (mean
MRI abnormalities—Only 1 dog had no abnormalities on MRI examinations
All other dogs had at least 1 abnormality for one of the assessed variables
Intervertebral disk degeneration—Nine of 37 (24%) dogs did not have evidence of intervertebral disk degeneration
Only partial intervertebral disk degeneration was detected in 14 (38%) dogs
Complete intervertebral disk degeneration was detected in another 14 (38%) dogs
Multiple affected disks were evident in 10 (27%) dogs
25 were partially degenerated and 17 were completely degenerated
The disks most frequently involved were C6-7 (n = 29 disks) and C5-6 (8)
Other affected disks were C2–3 (n = 3 disks) and C4-5 (2)
Severity of intervertebral disk degeneration and the sum of the scores of the assessed intervertebral disks were significantly associated with the higher age category (P = 0.005 and P = 0.003
respectively) but not with breed (P = 0.36 and P = 0.51
respectively) or sex (P = 0.98 and P = 1.00
Severity of disk degeneration was significantly (P < 0.001) associated with the location of the assessed intervertebral disk
with the more caudal intervertebral disk spaces significantly (P < 0.001) associated with the most severe degeneration
There was not a significant (P = 0.41) association between the location of the affected disk and age category
Disk-associated compression of the spinal cord—Three of 37 (8%) dogs did not have any sign of disk-associated compression
Partial compression of the ventral portion of the subarachnoid space was detected as the most severe compression in 9 (24%) dogs
Complete compression of the ventral portion of the subarachnoid space was detected as the most severe compression in 14 (38%) dogs
and compression of the spinal cord with deviation or distortion of the spinal cord was detected in 11 (30%) dogs
Multiple sites with some degree of compression were detected in 28 (76%) dogs
with 4 (11%) dogs having multiple sites of spinal cord compression
Among the 185 intervertebral disk spaces examined
88 had some degree of disk-associated compression; of these
43 had partial compression of the subarachnoid space
28 had complete compression of the subarachnoid space
The intervertebral disk spaces involved most often were C6-7 (n = 26 disks) and C4-5 (20)
Other affected intervertebral disk spaces were C2–3 (n = 15 disks)
Severity of disk-associated compression was significantly (P = 0.048) associated with the higher age category
the sum of the scores for the assessed intervertebral disk spaces was not significantly (P = 0.13) associated with age category
Severity and sum of the scores for disk-associated compressions were not significantly associated with breed (P = 0.58 and P = 0.44
respectively) or sex (P = 0.17 and P = 0.46
Severity of disk-associated compression was significantly (P = 0.004) associated with the location of the assessed intervertebral disk space
with the most severe compressions significantly (P = 0.019) associated with the more caudal intervertebral disk spaces
There was not a significant (P = 0.84) association between the location of the affected intervertebral disk space and age category
Compression of the dorsal portion of the spinal cord—Sixteen of 37 (43%) dogs did not have any sign of compression of the dorsal portion of the spinal cord
Partial compression of the dorsal portion of the subarachnoid space was detected as the most severe compression in 11 (30%) dogs
Complete compression of the dorsal portion of the subarachnoid space was detected as the most severe compression in 7 (19%) dogs
and compression of the dorsal portion of the spinal cord with deviation or distortion of the spinal cord was detected in 3 (8%) dogs
Multiple sites with any degree of compression of the dorsal portion of the spinal cord or subarachnoid space were detected in 9 (24%) dogs
For the 185 intervertebral disk spaces examined
30 had some degree of compression of the dorsal portion of the spinal cord or subarachnoid space; of these
19 had partial compression of the dorsal portion of the subarachnoid space
8 had complete compression of the subarachnoid space
and 3 had compression of the dorsal portion of the spinal cord
The involved intervertebral disk spaces were C6-7 (n = 17 disks)
Laminar malformations or abnormalities of the articular facets were not evident in any dog
Examination of images for the dorsal plane did not reveal any lateral compressions
Severity and sum of the scores of compression of the dorsal portion of the spinal cord or subarachnoid space were not significantly associated with age category (P = 0.66 and P = 0.71
Severity of compression of the dorsal portion of the spinal cord or subarachnoid space was significantly (P < 0.001) associated with the location of the assessed intervertebral disk space
with the most severe compressions significantly (P < 0.001) associated with the more caudally located intervertebral disk spaces
There was not a significant (P = 1.00) association between location of the affected intervertebral disk space and age category
Changes in signal intensity of the spinal cord—A hyperintense intramedullary signal change on T2-weighted images was evident in 2 of 37 (5%) dogs (2 Foxhounds of the higher age category at disk C4-5 and C5-6
A hypointense intramedullary signal change on T1-weighted images was not detected in any dog
There were no significant associations between changes in signal intensity of the spinal cord and age category (P = 0.46)
Vertebral body abnormalities—Vertebral body abnormalities were detected in 8 of the 37 (22%) dogs
this was evident as a flattening of the ventrocranial border of the vertebral body
These abnormalities were detected in 7 of 20 (35%) Doberman Pinschers at the level of C7 and in 1 Foxhound at the level of C6
Vertebral body abnormalities were significantly associated with the Doberman Pinscher as a breed (P = 0.043) but was not significantly associated with age category (P = 0.61) or sex (P = 0.82)
an additional abnormal position of the vertebral body with tipping or tilting of C7 was seen
Correlation between assessed variables—A significant correlation was detected between the severity of intervertebral disk degeneration and severity of disk-associated spinal cord compression (r = 0.52; P < 0.001)
sum of the scores for disk-associated compressions (r = 0.41; P = 0.003)
and severity of compression of the dorsal portion of the spinal cord or subarachnoid space (r = 0.31; P = 0.032)
The sum of the scores for intervertebral disk degeneration was significantly correlated with the severity of disk-associated compressions (r = 0.58; P < 0.001)
sum of the scores of disk-associated compressions (r = 0.50; P = 0.001)
and severity of compression of the dorsal portion of the spinal cord or subarachnoid space (r = 0.33; P = 0.002)
There also was a significant correlation between the severity of disk-associated compression and compression of the dorsal portion of the spinal cord (r = 0.30; P = 0.039) and between the severity of disk-associated compression and vertebral body abnormalities (r = 0.32; P = 0.037)
Follow-up monitoring—Eighteen of 20 Doberman Pinschers and 9 of 17 Foxhounds were available for physical and complete neurologic examinations between 16 and 18 months after the MRI examination performed during the study
These examinations revealed no abnormalities
The owner of 4 other Foxhounds was available for a telephone interview 9 months after the MRI examinations performed during the study
The remaining 2 Doberman Pinschers and 4 Foxhounds died of reasons unrelated to this study
these 6 dogs never had any clinical signs that were suggestive of a cervical myelopathy
None of these 6 dogs was available for postmortem examination
difficulties remain in extrapolating these data to other breeds and age categories
the dogs of our study were assigned to 2 age categories and
a breed with similar body conformation to that of Doberman Pinschers but no known predisposition to abnormalities of the cervical vertebral column was investigated
Analysis of results of the study reported here also indicated a surprisingly high frequency of abnormalities on MRI examinations of the clinically normal dogs
Although disk degeneration and partial compression of the ventral or dorsal portion of the subarachnoid space are not expected to complicate the clinical evaluation of MRI examinations
abnormalities of greater severity (such as spinal cord compression) have the potential to cause false-positive clinical interpretations
The relationship between these vertebral abnormalities and the subsequent development of cervical myelopathy is unclear
Because the incidence of vertebral abnormalities was not associated with the higher age category in these clinically normal dogs
it can be suggested that these abnormalities are not necessarily associated with the development of clinical signs in older dogs
the 2 dogs with a hyperintense intramedullary signal in the present study remained clinically normal 18 months after the MRI examination
Several significant correlations were detected between the assessed variables. The highest correlation existed between intervertebral disk degeneration and disk-associated compression of the spinal cord. This finding is not unexpected and is in agreement with findings in a study12 in humans
It indicates that a degenerated disk will be more likely to cause spinal cord compression
compared with the likelihood that a non-degenerated disk will cause spinal cord compression
It is important to emphasize that only 2 breeds were investigated in this study. These 2 breeds are not representative of the entire canine population, and it is possible that small-breed dogs would have another spectrum, frequency, and distribution of abnormalities.26 The selected breeds only represented dogs with a similar body conformation with and without a known predisposition for neurologic syndromes that involve the caudal portion of the cervical region
Analysis of the results of this study indicated that a wide variety of abnormalities evident during MRI examinations of the cervical region may not be clinically relevant in Doberman Pinschers and Foxhounds and that these abnormalities are commonly detected in the caudal portion of the cervical region of these breeds
This study further suggested that such lesions are part of the typical (or at least common) spinal cord degeneration associated with the aging process in dogs
caution should be used when attributing clinical signs to structural changes detected during MRI examinations
This is of particular importance for the caudal portion of the cervical region of large-breed dogs
Studies are necessary to determine the prevalence of false-positive interpretations for MRI examinations of the cervical spinal cord in clinically unaffected dogs and to investigate the use and development of diagnostic tools to differentiate between clinically relevant and clinically irrelevant spinal cord compressions detected during MRI examinations
and magnetic resonance imaging of the spine
Vet Clin North Am Small Anim Pract 1992;22:811–831
Complications associated with the use of iohexol for myelography of the cervical vertebral column in dogs: 66 cases (1988–1990)
Obstruction of contrast medium flow during cervical myelography
et al.Magnetic resonance imaging—a general overview of principles and examples in veterinary neurodiagnosis
Magnetic resonance imaging of the cervical spine in 27 dogs
et al.Comparison of magnetic resonance imaging and myelography in 18 Doberman Pinscher dogs with cervical spondylomyelopathy
et al.Detection of spinal cord compression in dogs with cervical intervertebral disc disease by magnetic resonance imaging
et al.Morphologic and morphometric magnetic resonance imaging features of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy
et al.Asymptomatic degenerative disk disease and spondylosis of the cervical spine: MR imaging
et al.Abnormal magnetic-resonance scans of the cervical spine in asymptomatic subjects
et al.Age-related MRI changes at 0.1 T in cervical disks in asymptomatic subjects
et al.MRI of cervical discs in asymptomatic subjects
Magnetic resonance imaging of the cervical spine: frequency of degenerative changes in the intervertebral disc with relation to age
et al.Presymptomatic spondylotic cervical cord compression
et al.Presymptomatic spondylotic cervical myelopathy: an updated predictive model
Disc-associated wobbler syndrome in the Doberman Pinscher
Vet Clin North Am Small Anim Pract 1988;18:667–696
Continuous dorsal laminectomy is the procedure of choice
et al.Outcome of medical and surgical treatment in dogs with cervical spondylomyelopathy: 104 cases (1988–2004)
Shape and orientation of articular facets of cervical vertebrae (C3–C7) in dogs denoting axial rotational ability: an osteological study
A morphometric investigation on breed-specific features affecting sagittal rotational and lateral bending mobility in the canine cervical spine (C3–C7)
Effects of torsion on lumbar intervertebral joints: role of torsion in production of disc degeneration
Presence of cervical vertebral malformation in Doberman puppies and the effects of diet and growth rate
Magnetic resonance imaging and cervical spondylotic myelopathy
et al.Spinal-cord morphology and pathology in ossification of the posterior longitudinal ligament
et al.A retrospective comparison of cervical intervertebral disk disease in nonchondrodystrophic large dogs versus small dogs
OBJECTIVE To compare ammonia concentrations in arterial blood
and CSF samples of dogs with and without extrahepatic portosystemic shunts (EHPSS)
ANIMALS 19 dogs with congenital EHPSS and 6 healthy control dogs
PROCEDURES All dogs underwent a physical examination and then were anesthetized for transsplenic portal scintigraphy to confirm the presence or absence of EHPSS
arterial and venous blood samples and a CSF sample were simultaneously collected for determination of ammonia concentration
which was measured by use of a portable blood ammonia analyzer (device A) and a nonportable biochemical analyzer (device B)
Results were compared between dogs with EHPSS and control dogs
and CSF ammonia concentrations for dogs with EHPSS were significantly greater than those for control dogs
ammonia concentrations in both arterial and venous blood samples were markedly increased from the reference range
There was a strong positive correlation between arterial and venous ammonia concentrations and between blood (arterial or venous) and CSF ammonia concentrations
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that blood and CSF ammonia concentrations in dogs with EHPSS were greater than those for healthy dogs and were strongly and positively correlated
This suggested that the permeability of the blood-brain barrier to ammonia may be abnormally increased in dogs with EHPSS
but further investigation of the relationship between blood or CSF ammonia concentration and clinical signs of hepatic encephalopathy or the surgical outcome for dogs with EHPSS is warranted
It is widely accepted that ammonia is a key factor in the pathogenesis of HE.6 Ammonia initiates HE by altering astrocyte function. Astrocytes are the main cells that metabolize ammonia in the brain. The conversion of glutamate and ammonia to glutamine causes osmotic stress, which results in astrocyte swelling, cerebral edema, and intracranial hypertension.7
The objective of the study reported here was to compare ammonia concentrations in arterial blood
and CSF samples between dogs with and without congenital EHPSS in an attempt to elucidate the pathogenesis of HE
We hypothesized that the arterial ammonia concentration would be greater than the venous ammonia concentration in dogs with EHPSS and that there would be a positive correlation between ammonia concentrations in the blood and CSF
All study procedures were approved by the Ethical Committee of the Faculty of Veterinary Medicine of Ghent University (EC2012/164 and EC2013/33) and by the Belgian Deontological Committee
Six healthy adult Beagles from a research colony (controls) and 19 client-owned dogs with congenital EHPSS were prospectively evaluated between July 2012 and October 2015
Owner consent was obtained for all dogs with a congenital EHPSS prior to study enrollment
Blood samples (1.0 mL) for preprandial and postprandial serum bile acid concentration analysis were collected by jugular venipuncture from each dog. Following collection of the preprandial blood sample, each dog was fed 2 teaspoons of a commercial highly digestible protein and fat diet,a and the postprandial blood sample was collected 2 hours later
IV to effect) and maintained with a constant rate infusion of propofol (0.2 to 0.4 mg/kg/min
1 L/min) was supplied through the endotracheal tube for the duration of the anesthetic session
Prior to the transsplenic portal scintigraphy procedure, an arterial blood sample (700 μL) was collected from a femoral artery by use of a 25-gauge needle attached to a 1-mL syringe. Then, a venous blood sample (700 μL) was collected from a jugular vein by use of a 21-gauge needle attached to a 2.5-mL syringe. Each blood sample was transferred to a specialized heparinized whole blood separator tubed immediately after collection
and the tubes were placed on melting ice and immediately submitted to an in-house laboratory for determination of ammonia concentration
a small area (3 × 3 cm) of skin over the atlanto-occipital region was clipped and aseptically prepared
A CSF sample (0.5 mL) was aseptically collected via a cisternal puncture with a 21-gauge needle
The CSF sample was collected directly into a sterile tube without additives
Similar to the arterial and venous blood samples
the tube containing the CSF sample was immediately placed on melting ice and submitted to an in-house laboratory for determination of ammonia concentration
Transsplenic portal scintigraphy was performed as described21 to determine the presence (dogs with EHPSS) or absence (control dogs) of PSS. Briefly, intrasplenic injection of sodium pertechnetatee was performed with ultrasound guidance, and a dynamic scan was simultaneously initiated with a nuclear γ cameraf equipped with a low-energy
Blood samples obtained for preprandial and postprandial bile acid analysis were centrifuged
The serum samples were then sent to an external laboratory for bile acid analysis
a WBC count was performed manually by microscopic examination
Statistical analyses were performed by use of a commercial software package.j Data distributions were checked for normality by use of the Kolmogorov-Smirnov test with Lilliefors significance correction
The mean ± SD was reported for data that were normally distributed
and the median (range) was reported for data that were not normally distributed
Comparisons between dogs with EHPSS and control dogs were performed with an unpaired t test or Mann-Whitney U test for independent continuous variables that were and were not normally distributed
and a paired t test or Wilcoxon signed rank test for paired data (eg
preprandial and postprandial serum bile acid concentrations) that were and were not normally distributed
Correlation was assessed with the Pearson product-moment coefficient (r) or Spearman rank coefficient (p) for variables that were and were not normally distributed
Values of P ≤ 0.05 were considered significant for all analyses
The control Beagles consisted of 3 spayed females and 3 castrated males and ranged in age from 36 to 54 months and in body weight from 9.1 to 16.0 kg
The dogs with EHPSS consisted of 5 sexually intact females
and 2 castrated males and ranged in age from 3 to 65 months and in body weight from 1.5 to 13.4 kg
Dogs with EHPSS included Yorkshire Terriers (n = 4)
None of the control dogs had clinical signs of HE (HE grade = 0)
15 had signs of apathy and some degree of head pressing
Preprandial and postprandial serum bile acid concentrations for the controls and dogs with EHPSS were summarized (Table 1)
all serum bile acid concentrations were well within the reference range (< 19 μmol/L)
27 to 381 μmol/L) and postprandial (218 μmol/L; range
49 to 656 μmol/L) serum bile acid concentrations for the dogs with EHPSS were significantly (P < 0.001) greater than those for controls
preprandial and postprandial serum bile acid concentrations
and arterial and venous blood and CSF ammonia concentrations as determined by 2 devices for 6 healthy adult Beagles (controls) and 19 dogs with EHPSS
Values represent the median (range) or mean ± SD
Clinical signs of HE were graded on a 5-point scale
where 0 = clinically normal; 1 = abnormally decreased mobility or mild apathy; 2 = severe apathy or mild ataxia; 3 = salivation
Ammonia concentrations in arterial and venous blood samples and CSF samples were measured in parallel by a portable blood ammonia analyzer (device A) and nonportable biochemical analyzer (device B)
All values for dogs with EHPSS were significantly (P < 0.001) greater than the corresponding values for the control dogs
*Value differs significantly (P < 0.001) from the corresponding value measured by device A
†Value differs significantly (P < 0.05) from the arterial ammonia concentration measured by the same device
Ammonia concentrations in arterial and venous blood samples and CSF samples were summarized (Table 1)
The mean arterial and venous ammonia concentrations for dogs with EHPSS were significantly (P < 0.001) greater than those for controls
The arterial and venous ammonia concentrations measured by device A were significantly greater (P < 0.001) than those measured by device B for dogs with EHPSS; nevertheless
there was a strong positive correlation between the ammonia concentrations measured by devices A and B for both arterial (r = 0.884) and venous (r = 0.819) blood samples
Although arterial ammonia concentrations were greater than venous ammonia concentrations
only those measured by device A differed significantly (P < 0.05)
There was a strong positive correlation between arterial and venous ammonia concentrations measured by device A (r = 0.960) and device B (r = 0.900)
positive correlation between preprandial serum bile acid concentration and venous ammonia concentration measured by device A (ρ = 0.461) and device B (ρ = 0.486) as well as between postprandial serum bile acid concentration and venous ammonia concentration measured by device A (ρ = 0.414) and device B (ρ = 0.394)
positive correlation between HE grade and arterial ammonia concentration measured by device A (ρ = 0.445) and device B (ρ = 0.461)
All CSF samples were macroscopically normal
and the CSF WBC count was within the reference range (< 8 cells/μL) for all controls and dogs with EHPSS
The mean CSF ammonia concentration for dogs with EHPSS was significantly (P < 0.001) greater than that for controls
The mean CSF ammonia concentration measured by device A was significantly (P < 0.001) greater than that measured by device B
There was a strong significant (P < 0.001) positive correlation between arterial and CSF ammonia concentrations measured by device A (r = 0.884) and device B (r = 0.870) as well as between venous and CSF ammonia concentrations measured by device A (r = 0.892) and device B (r = 0.725)
The HE grade was not significantly (P = 0.09) correlated with CSF ammonia concentration measured by device A
but there was a significant (P = 0.05) weak positive correlation (ρ = 0.396) between HE grade and CSF ammonia concentration measured by device B
Results of the present study indicated that ammonia concentrations in arterial and venous blood samples and CSF samples of dogs with EHPSS were significantly greater than those for healthy control dogs
There was also a strong positive correlation between ammonia concentrations in the CSF and blood regardless of whether it was arterial or venous
In human patients with HE, disease severity is positively correlated with blood ammonia concentration,31 and an arterial ammonia concentration ≥ 150 μmol/L is associated with a negative prognosis.17,18 There is also a strong positive correlation between disease severity and blood ammonia concentration in dogs with HE.19 In the present study
the blood ammonia concentration for dogs with HE (regardless of disease severity) was significantly greater than that for healthy dogs; however
the correlations between blood ammonia concentrations and disease severity (ie
HE grade) were rather weak for dogs with EHPSS
mean arterial ammonia concentration was greater than the mean venous ammonia concentration for the dogs with EHPSS in the present study; however
that difference was statistically significant only when the ammonia concentration was measured by device A
In the present study, dogs with EHPSS had high CSF ammonia concentrations that were strongly and positively correlated with blood ammonia concentrations. Investigators of other studies7,14 have presumptively stated that the ammonia concentration is abnormally increased in the CSF of dogs with congenital EHPSS without actually measuring the CSF ammonia concentration
Data regarding CSF ammonia concentration are lacking
likely because of a paucity of validated techniques to measure the ammonia concentration in CSF
2 commercial devices (device A and device B) were used to measure ammonia concentration in blood samples as well as CSF samples
The respective test slides for each device contain a buffer in the top layer that converts ammonium ions in the sample into gaseous ammonia
which passes through a selectively permeable membrane and reacts with a pH indicator (bromocresol green for device A and bromophenol blue for device B)
color development is proportional to the amount of ammonia in the sample
no device has been validated to measure the ammonia concentration in CSF
the CSF ammonia concentration measured by device A was consistently greater than that measured by device B
there was a strong positive correlation between the ammonia concentration measured in blood (arterial or venous) and that measured in CSF
which suggested that either device can be used in clinical practice to provide an estimate of the CSF ammonia concentration
the CSF ammonia concentrations measured in the present study should be interpreted cautiously in a comparative rather than absolute manner until the devices have been validated for measurement of the ammonia concentration in CSF samples
the ammonia concentrations in both the blood and CSF of dogs with EHPSS were significantly greater than the corresponding concentrations in the healthy controls
which suggested that an increasing concentration of ammonia in the brain can lead to toxicosis and severe clinical signs of HE
we could not definitively rule out the possibility that seizures and other clinical signs of HE in some of the dogs with EHPSS were caused or triggered by another neurodegenerative disease process
If the clinical signs of HE were indeed induced by an increase in cerebral ammonia concentration
administration of a medical treatment regimen that alters the ratio between the ionic and gaseous forms of ammonia might decrease the influx of ammonia into the CSF and brain prior to surgery to correct the EHPSS
preprandial and postprandial serum bile acid concentrations were only weakly correlated with venous ammonia concentration
Only a limited number of dogs with various degrees of HE were evaluated
and samples need to be processed with special care so as not to influence the test results
Precautions such as the use of melting ice for sample transport and the nearly immediate processing of samples (time from sample collection to measurement of ammonia concentration was < 120 seconds for all samples) and discarding of CSF samples that were grossly contaminated with blood should have minimized the risk for preanalytic errors
although they can never be completely excluded
the CSF ammonia concentrations for dogs with EHPSS were significantly greater than those for healthy control dogs
and there was a strong positive correlation between the ammonia concentrations in the CSF and blood
which suggested that the permeability of the BBB to ammonia may be abnormally increased in dogs with EHPSS
the ammonia concentration was markedly increased from the reference range in both arterial and venous blood samples
can be substituted for arterial blood samples
which can be difficult to obtain and often require anesthetizing the patient
for measurement of blood ammonia concentration
because ammonia passes through the BBB into the brain in a nonlinear manner relative to the blood ammonia concentration
caution is necessary to ensure that the presence or severity of HE is not underestimated when blood ammonia concentrations are interpreted
Further investigation of the relationship between blood or CSF ammonia concentration and clinical signs of HE or the surgical outcome for dogs with EHPSS is warranted
Supported in part by a European College of Veterinary Surgeons’ Surgeon-in-Training Research Grant
Presented in part at the 23rd Annual Scientific Meeting of the European College of Veterinary Surgeons
The authors thank Sara Kol for language editing
Clinical investigation of a point-of-care blood ammonia analyzer
Diagnostic value of fasting plasma ammonia and bile acid concentrations in the identification of portosystemic shunting in dogs
Hyperammonemia due to a urea cycle enzyme deficiency in two dogs
Transient hyperammonemia due to urea cycle enzyme deficiency in Irish Wolfhounds
and clinicopathologic features of portosystemic vascular anomalies in the dog and cat
Semin Vet Med Surg (Small Anim) 1990; 5: 83–93
Glutamine as a pathogenic factor in hepatic encephalopathy
diagnosis and management of hepatic encephalopathy
Nat Rev Gastroenterol Hepatol 2010; 7: 515–525
Fine structural localization of glutamine synthetase in astrocytes of rat brain
The role of astrocytes in hepatic encephalopathy
Blood ammonia levels and hepatic encephalopathy
Cerebral ammonia metabolism in patients with severe liver disease and minimal hepatic encephalopathy
J Cereb Blood Flow Metab 1991; 11: 337–341
Congenital portosystemic shunts in dogs and cats
Selective alterations of cerebrospinal fluid amino acids in dogs with congenital portosystemic shunts
and tryptophan metabolite concentrations in dogs with portosystemic shunts
Improvement of chronic hepatic encephalopathy in dogs by the benzodiazepine-receptor partial inverse agonist sarmazenil
Predictive value of arterial ammonia for complications and outcome in acute liver failure
Arterial ammonia and clinical risk factors for encephalopathy and intracranial hypertension in acute liver failure
Arterial and venous ammonia concentrations in the diagnosis of canine hepato-encephalopathy
Brain magnetic resonance imaging characteristics in dogs and cats with congenital portosystemic shunts
Use of 99mTCO4(−) trans-splenic portal scintigraphy for diagnosis of portosystemic shunts in 28 dogs
In vivo proton magnetic resonance spectroscopy for the evaluation of hepatic encephalopathy in dogs
Effects of liver disease and hyperammonemia
Astrocyte glutamine synthetase: importance in hyperammonemic syndromes and potential target for therapy
Hyperammonemia-induced toxicity for the developing central nervous system
In vivo studies of brain metabolism in animal models of hepatic encephalopathy using 1H magnetic resonance spectroscopy
Glutamine as a mediator of ammonia neurotoxicity: a critical appraisal
Correlation between ammonia levels and the severity of hepatic encephalopathy
Regional cerebral blood flow assessed by single photon emission computed tomography (SPECT) in dogs with congenital portosystemic shunt and hepatic encephalopathy
Blood-brain barrier permeability to ammonia in liver failure: a critical reappraisal
Sensitivity and specificity of fasting ammonia and serum bile acids in the diagnosis of portosystemic shunts in dogs and cats
Objective—To determine the clinical effects and pharmacokinetics of amiodarone after single doses of 5 mg/kg administered orally or intravenously
clinical signs and electrocardiographic variables were monitored and plasma and urine samples were collected
A liquid chromatography–mass spectrometry method was used to determine the percentage of protein binding and to measure plasma and urine concentrations of amiodarone and the active metabolite desethylamiodarone
Results—No adverse clinical signs were observed
median terminal elimination half-lives of amiodarone and desethylamiodarone were 51.1 and 75.3 hours
and the apparent volume of distribution for amiodarone was 31.1 L/kg
The peak plasma desethylamiodarone concentration of 0.08 μg/mL was attained 2.7 hours after IV administration
Neither parent drug nor metabolite was detected in urine
absorption of amiodarone was slow and variable; bioavailability ranged from 6.0% to 33.7%
The peak plasma amiodarone concentration of 0.14 μg/mL was attained 7.0 hours after oral administration and the peak plasma desethylamiodarone concentration of 0.03 μg/mL was attained 8.0 hours after administration
Median elimination half-lives of amiodarone and desethylamiodarone were 24.1 and 58.6 hours
Conclusion and Clinical Relevance—Results indicate that the pharmacokinetic distribution of amiodarone is multicompartmental
This information is useful for determining treatment regimens for horses with arrythmias
Amiodarone has low bioavailability after oral administration
the present study was undertaken to investigate the pharmacokinetics of orally and IV administered amiodarone in horses
Study design—In a crossover format, the first phase of the study involved IV administration of a single dose (5 mg/kg) of amiodaroneb to 3 healthy Standardbred mares with mean ± SD age
and height at the withers of 9.8 ± 3.5 years
Horses received the dose of amiodarone as a bolus in the right jugular vein over a period of 2 minutes
Three other horses received an orally administered dose (5 mg/kg) of crushed tablets by means of nasogastric intubation after being withheld from feed for 12 hours
Four hours after receiving the oral treatment
Blood was withdrawn from the left jugular vein in heparinized polyethylene tubes just before drug administration; 5
and 720 minutes after administration; and every 12 hours after that until 7 days after administration
Blood samples were centrifuged at 3,000 × g immediately after collection to obtain plasma
Plasma and urine samples were frozen and stored at −18°C until drug assay
and an ECG were recorded at each blood sampling time until 6 hours after drug administration
Information collected from ECG included heart rate
Immediately before and 7 days after drug administration
complete hematologic and biochemical blood analyses were performed
which was initiated 60 days after the first phase
Horses that had received amiodarone IV in the first phase were treated orally and vice versa
The experimental protocol was approved by the Ethics Committee of the Faculty Veterinary Medicine at Ghent University
An isocratic run of 5 minutes was performed with a mobile phase of acetonitrile (A) and 0.1% formic acid in water (B; ratio
80A:20B[vol/vol]) at a flow rate of 0.2 mL/min
Quantification was performed by use of ion transitions with mass-over-charge ratios of 646.1 > 572.8 for amiodarone and 618.2 > 546.8 for desethylamiodarone
The between-day trueness and precision were determined by use of samples of plasma with a drug concentration of 0.010 µg/mL and were used for quality control during analyses of the collected samples
Those values were in the specified maximum ranges
The LOQs for plasma and urine were established by analyzing 6 blank samples to which amiodarone and desethylamiodarone (concentration
The LOD was calculated by means of the criterion of a signal-to-noise ratio of 3:1
This corresponded to LODs of 0.0001 and 0.00004 µg/mL
for amiodarone and desethylamiodarone in plasma and of 0.00016 and 0.00009 µg/mL
Protein binding was determined in plasma samples (n = 6) to which drug had been added at a concentration of 2 µg/mL and allowed to equilibrate for 30 minutes at 37°C. One milliliter of that solution was centrifuged at 9,500 × g for 10 minutes through a filtere of 30.000 molecular-weight cutoff
The filtrate was analyzed similarly to plasma samples
For amiodarone data obtained after oral administration and desethylamiodarone data obtained after IV and oral administration (of amiodarone)
noncompartmental methods were used because standard fitting procedures resulted in poor correlations
The AUC0–inf value was calculated via the trapezoidal method
The variables Cmax and Tmax were observed directly from the plasma concentration time plots
Absolute bioavailability (F) was calculated from the following equation:
Statistical analysis—Pharmacokinetic variables were reported as median values except for t1/2el, for which a harmonic mean was calculated. Respiratory rate, heart rate, P-R interval, QRS duration, and Q-T interval over time were analyzed by use of single-factor ANOVA.g The mean measured values were compared with values obtained before treatment
values of P < 0.05 were considered significant
Administration of amiodarone via IV and oral routes was tolerated well by all horses. Values for hematologic and serum biochemical variables remained within reference ranges21 for the first (ie
immediately before administration) and second (ie
7 days after administration) blood samples
Numeric and graphic descriptions of data for respiratory rate
and QT interval indicated that the condition of equality of variances was satisfied
Results of single-factor ANOVA did not reveal significant differences between mean values for the variables
Although increased heart rate was observed after IV administration of amiodarone
Pharmacokinetic variables for amiodarone and desethylamiodarone were given as median and range values and summarized (Tables 1 and 2). Mean ± SD plasma concentrations of amiodarone and desethylamiodarone after IV and oral administration were plotted (Figures 1 and 2)
plasma concentrations of amiodarone and desethylamiodarone were quantifiable from 5 and 15 minutes
after administration until 168 hours after administration
amiodarone and desethylamiodarone concentrations were quantified in plasma from 30 and 90 minutes
after administration until 96 and 120 hours after administration
plasma concentrations of amiodarone decreased rapidly in the first phase of the 3-compartment model
The second phase was characterized by a slower decline in concentration and was followed by a very slow decline in concentration in the third phase
there was a small increase (50 and 100 µg/mL) in plasma amiodarone concentration at 8 and 12 hours
The plasma concentration curves after oral administration of the drug were variable
Protein binding of amiodarone as analyzed at 2 µg/mL was 96%
No amiodarone or desethylamiodarone could be detected in the urine samples collected until 12 hours after IV administration
Figure 1—Mean ± SD plasma concentrations of amiodarone and desethylamiodarone after a single IV administered dose (5 mg of amiodarone/kg) in 6 healthy horses
Citation: American Journal of Veterinary Research 67, 3; 10.2460/ajvr.67.3.448
Figure 2—Mean ± SD plasma concentrations of amiodarone and desethylamiodarone after a single orally administered dose (5 mg/kg) of amiodarone in the same horses as in Figure 1
Median and range values of pharmacokinetic variables after a single IV or orally administered dose (5 mg/kg) of amiodarone in 6 healthy horses
Median and range values of pharmacokinetic variables for desethylamiodarone after a single IV or orally administered dose (5 mg/kg) of amiodarone in the same 6 horses as in Table 1
Comparison of pharmacokinetic variables should
be performed with data collected under the same circumstances
including similar sampling times and sensitivity of analytic methods
Whether food intake also increases bioavailability of orally administered amiodarone in horses remains to be investigated
A secondary peak in plasma concentration 8 to 12 hours after IV administration was observed in 2 horses and may have been a result of enterohepatic cycling.32 The fact that the highest bioavailability for amiodarone was observed in those 2 horses supports this theory
This may indicate that there is a species-dependent difference in metabolism
with N-dealkylation being a less important metabolic pathway in horses than in humans
long-term administration studies should be performed
with analysis of plasma and liver tissue for amiodarone and desethylamiodarone concentrations
and in vitro experiments with microsomes obtained from equine liver tissue could be performed to confirm this hypothesis
but no clinical data from horses treated via this protocol have been published
Another possibility would be a treatment protocol combining IV and oral dosing
in which the IV dose could be administered in a clinic setting and plasma drug concentrations could be measured
Use of such a protocol would potentially permit slower increases in plasma drug concentrations toward the desired steady-state concentration with fewer adverse effects but would have the disadvantage of increased treatment costs
Results of the present study confirm that the pharmacokinetics of amiodarone and desethylamiodarone in horses are multicompartmental
The drug is poorly bioavailable after oral administration
further pharmacokinetic and pharmacodynamic studies are needed to develop a safe treatment protocol for amiodarone in horses
Studies of long-term dosing and clinical effects and use of more sensitive analytic techniques are needed before amiodarone can feasibly be administered to horses with chronic AF
Pacing induced long-term atrial fibrillation in horses (abstr)
Amiodarone: historical development and pharmacologic profile
Amiodarone: guidelines for use and monitoring
Use of population modeling to define rational monitoring of amiodarone hepatic effects
An overview of its pharmacological properties
and review of its therapeutic use in cardiac arrhythmias
et al.Pharmacokinetics and pharmacodynamic effects of amiodarone in plasma of ponies after single intravenous administration
A review of class III antiarrhythmic agents for atrial fibrillation: maintenance of normal sinus rhythm
Factors affecting prognosis and conversion in equine atrial fibrillation
Echocardiography and therapy of atrial fibrillation in horses [in German]
Dtsch Tierarztl Wochenschr 1994;101:190–194
Treatment of atrial fibrillation in horses by intravenous administration of quinidine
et al.An echocardiographic study of atrial fibrillation in horses: before and after conversion to sinus rhythm
Treatment of atrial fibrillation in horses: new perspectives
et al.Transvenous electrical cardioversion in equine atrial fibrillation: technique and successful treatment of 3 horses
Pharmacological cardioversion of atrial fibrillation: current management and treatment options
et al.Use of intravenous flecainide in horses with naturally-occurring atrial fibrillation
et al.Intravenous amiodarone treatment in horses with chronic atrial fibrillation
et al.Safe and efficacious dosage of flecainide acetate for treating equine atrial fibrillation
Application of Akaike’s Information Criterion (AIC) in the evaluation of linear pharmacokinetic equations
Multicompartment models: three compartment model
et al.Electrocardiographic and antiarrhythmic effects of intravenous amiodarone: results of a prospective
et al.Chronic amiodarone evokes no torsades de pointes arrhythmias despite QT lengthening in an animal model of acquired long-QT syndrome
et al.A comparison of the electrophysiologic effects of intravenous and oral amiodarone in the same patient
Pharmacodynamics of intravenous amiodarone in the dog
et al.Amiodarone as a first-choice drug for restoring sinus rhythm in patients with atrial fibrillation: a randomized
The anomalous pharmacokinetics of amiodarone explained by nonexponential tissue trapping
Population pharmacokinetics of long-term oral amiodarone therapy
et al.Bioavailability of amiodarone tablets administered with and without food in healthy subjects
Comparative study of transit and metabolism of amiodarone in different species of animals and humans [in French]
Arch Int Pharmacodyn Ther 1969;177:340–359
et al.Pharmacokinetics of amiodarone after intravenous and oral administration
et al.Clinical pharmacokinetics and efficacy of amiodarone for refractory tachyarrhythmias
et al.Amiodarone for tachyarrhythmias: pharmacology
et al.Pharmacokinetics and body distribution of amiodarone in man
et al.Pharmacokinetics of amiodarone in man
Single-dose kinetics of tissue distribution
excretion and metabolism of amiodarone in rats
Plasma protein binding of amiodarone in a patient population: measurement by erythrocyte partitioning and a novel glass-binding method
et al.Disposition of intravenous amiodarone in subjects with normal and impaired renal function
Iodine kinetic studies during amiodarone treatment
et al.Early-onset acute toxic hepatitis induced by intravenous amiodarone administration [in Spanish]
Acute hepatitis complicating intravenous amiodarone treatment
et al.Atrial fibrillationin the horse: retrospective study on 30 subjects
The slightly uphill drag to the line favoured the Belgian
three stages in the UAE Tour and two in the AlUla Tour so far this year
It was a tactical battle for the stage win
and Merlier took advantage of Philipsen's reluctance to start the sprint
"I felt it was the right moment," Merlier said
"We didn't have a lot of speed because of the headwind
I knew we had everything under control in the final kilometres
I deliberately stayed in the wheels after the last turn."
Merlier said he wasn't on his best form after racing the Giro d'Italia and was surprised to win the stage
especially against the fresher riders here," Merlier said
"I've done this stage quite a few times before
and I've never won a stage in the Tour of Belgium before
Stage 1 winner Søren Wærenskjold (Uno-X) managed to keep a narrow lead in the general classification after coming seventh on the stage and snatching one of the intermediate sprint bonuses
"I was a little too tired to sprint but I still have one second lead," Wærenskjold said
"When I came into the finish it was a little hard so I didn't have the best legs
the sprinters were highly motivated to contest stage 2 of the 2024 Tour of Belgium
an 184.2-kilometre stage from Merelbeke to Knokke-Heist
The mostly flat stage had some climbs and cobbles familiar to riders from Omloop Het Nieuwsblad and Nokere Koerse
but these obstacles were largely limited to the first half of the stage
It took almost an hour for the day's breakaway to be established
the WorldTour teams kept the gap to an easy-to-close level
Seven riders from lower-ranked teams made up the move with Ward Vanhoof (Flanders-Baloise)
Gianni Marchand (Tarteletto Isorex) and Max Kroonen (Volkerwessels) getting a maximum of 1:45
and the race was all back together with 75km to go
Dries De Bondt (Decathlon AG2R La Mondiale) won the sprint in Damme with 48km to go
The peloton hit the closing circuits all together
Visma-Lease a Bike and Soudal-Quickstep fighting for control
Philipsen found himself with Olav Kooij on his wheel and delayed his jump
while Merlier took advantage of the delay to sprint away to the stage win
Results powered by FirstCycling
she coordinates coverage for North American events and global news
As former elite-level road racer who dabbled in cyclo-cross and track
Laura has a passion for all three disciplines
When not working she likes to go camping and explore lesser traveled roads
UCI governance and performing data analysis
The IKF Korfball Champions League Final has its champion: the Dutch club PKC/Vertom
after beating by 19-10 Fortuna/Delta Logistiek in the big final
The Belgian Borgerhout/Groen-Wit KC and Floriant Merelbeke played an exciting and tight game for 3rd place
that was decided by 18- 19 in favour of Floriant in the last minutes
this final event was taking place in the Dutch city of Delft
between the best four korfball clubs in Europe playing to win the 1st edition of this new European club trophy
All fans and supporters were welcome to see the matches live at Fortuna Hall (buy tickets), or they could also enjoy the 4 matches scheduled watching the live streams through the Olympic Channel
The signal were be produced by the IKF and broadcasted live trough the Olympic Channel platform
as part of a collaboration and partnership between these two organisations
The IKF is an international federation officially recognised by the Olympic International Committee
korfball content has been broadcasted several times
specially during the World Games 2017 and 2022
This IKF KCL Final was expected to be the first of many more events and korfball content to be broadcasted during the next years
fans were able to watch these live streams next to all the statistics
live results and scorers and play-by-play actions
SEMI-FINALS (in English): Watch the live stream here (streaming starts at 17:15 h)
SF1 (18:00h) Borgerhout/Groen-Wit KC, BEL 9-22 Fortuna/Delta Logistiek, NEDSF2 (20:00h) Floriant Merelbeke, BEL 13-21 PKC/Vertom, NED
SEMI-FINALS (in Dutch): Watch the live stream here (streaming starts at 17:15 h)
3rd PLACE & FINAL (in English): Watch the live stream here (streaming starts at 16:15 h)
For 3rd Place: Borgerhout/Groen-Wit KC, BEL 18- 19 Floriant Merelbeke, BELFinal: PKC/Vertom, NED 19-10 Fortuna/Delta Logistiek, NED
3rd PLACE & FINAL (in Dutch): Watch the live stream here (streaming starts at 16:15 h)
More information (Olympic Channel): www.olympics.com/en/sport-events/2023-ikf-korfball-champions-league-final-delft
The Royal Dutch Korfball Association and Korfbalvereniging Fortuna/Delta Logistiek
The previuos rounds of this IKF Korfball Champions League 2022-2023 were played as follows:
All fans around the world were be able to follow this tournament live on www.worldkorfball.sport (with live results and streams, statistics, scorers, play-by-play, …) and live on the Olympic Channel
clips and highlights were be published and shared on all IKF profiles (see below) and via the hashtags #KCL and #korfball:
youtube.com/IKFchannel
facebook.com/korfball.org
twitter.com/korfball
instagram.com/korfball_org
tiktok.com/@korfball.sport
Event info: https://korfball.sport/?p=29805
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Ghent University redesigns the university campuses in an ambitious future plan: a long-term vision in which the 11 faculties will be housed in three clusters by 2050
The 3 university clusters would be on one virtual axis from the centre of the city of Ghent across Campus Sterre and UZ Gent to the south of Ghent by 2050
Some traditional university campuses will be abandoned
Ghent University wants to rethink the infrastructure in function of the challenges that will arise in the coming decades
four faculties (or in some cases: a specific part of a faculty) will each be grouped by cluster
The implementation of this vision will be accompanied by ongoing consultations at both local and supra-local levels in the coming years
the necessary permits to implement this plan are crucial and numerous
Ghent University will start consultations with both the local and Flemish authorities in the short term
This means that Campus Coupure (Faculty of Bioscience Engineering)
Campus Dunant (Faculty of Psychology and Educational Sciences)
Campus Schoonmeersen (the Ghent University activities)
Campus Heide (part of Faculty of Veterinary Medicine)
Campus Mercator (part of Faculty of Arts and Philosophy) and Campus Rommelaere (currently no occupancy) will be vacated by 2050
The research and teaching activities taking place on these campuses or in these buildings will be relocated
Buildings that are abandoned may be given in concession or long lease to an external party
the university outlines the choices to be made now and in the near future
research and service provision are central to Ghent University's core tasks
mobility and digitisation are also major challenges and opportunities
The plan allows for an optimal response to these
Ghent University is focusing on shared facilities within the core campuses in order to achieve a high-quality
this vision will be central to every decision concerning Ghent University's patrimony
Every building project or renovation plan will be tested against it.