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A 6-year-old neutered male mixed-breed dog (dog 1) and 5-year-old neutered male Boston Terrier (dog 2) were evaluated because of lateralized multilobular osteochondrosarcoma (MLO) of the occiput.


Diagnostic imaging revealed proliferative bony occipital masses in both dogs and a nodule in the right caudal lung lobe of dog 1. For both dogs, MRI revealed intact flow through the dorsal sagittal sinus (DSS) into 1 transverse sinus.


In dog 1, a 4F balloon catheter was introduced into the DSS to the confluens sinuum (CS) and inflated over 16 hours to occlude venous flow. The mass with the CS was removed 24 hours later, and the skull was reconstructed. The dog was discharged from the hospital 2 days after surgery and survived 17 months before euthanasia because of metastasis. In dog 2, balloon catheter insertion into the DSS failed, and a 3.5F rubber catheter was placed up to the CS to occlude flow. The occiput with MLO was removed 48 hours after catheterization, and the skull was reconstructed. Dog 2 was discharged from the hospital after 3 days and was doing well 15 months later.


Findings for these 2 dogs suggested that deliberate preoperative occlusion of the DSS and CS allows successful resection of occipital neoplasms across the midline. Without prior occlusion of the DSS, development of lethal cerebral edema would have been likely. Gradual balloon catheter occlusion of the CS may facilitate challenging occipital mass excisions.

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in Journal of the American Veterinary Medical Association


Objective—To determine the ultrasonographic appearance and detectability of edema induced by SC injection of mild silver protein suspension in the mammary gland attachments of dairy cows.

Design—Prospective study.

Animals—6 lactating cows.

Procedure—In each cow, the number of quarters that received injections was randomly assigned. A mild silver protein susoension was injected SC into cranial and caudal mammary gland attachment sites. The number of injections and volume injected were determined on the basis of the appearance of the mammary gland and the desired subjective visual effect. Seventeen sites were chosen for injection and 7 sites did not receive injections. Ultrasonographic images were obtained 1 day prior and 6 days after injections were started. Cows received injections 1, 3, and 5 days after initial sonography. The sonographer was unaware of which sites received injections.

Results—Ultrasonography revealed alternating hypoechoic and hyperechoic bands at injection sites. Certain injections caused the intimal surface of the subcutaneous abdominal vein to develop a corrugated appearance. All injection sites were correctly identified ultrasonographically (100% sensitivity, 100% specificity) with a positive and negative predictive value of 1.0.

Conclusions and Clinical Relevance—Results suggest that mild silver protein suspension injected SC to enhance the appearance of the mammary glands of dairy cows can be readily detected by ultrasonography. Detection of injection sites should be made on the basis of the distribution and ultrasonographic appearance of edema. (J Am Vet Med Assoc 2002;221:408–410)

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in Journal of the American Veterinary Medical Association


OBJECTIVE To determine the size of the left and right kidneys by use of CT in dogs of various breeds without evidence of renal disease.

DESIGN Retrospective, observational study.

ANIMALS 21 client-owned dogs.

PROCEDURES Renal length, diameter of the abdominal aorta, and length of the L2 vertebral body were measured independently on multiplanar reformatted non–contrast-enhanced CT images by 3 observers at 3 time points. Intraobserver and interobserver agreement for renal length were determined. Associations of renal length with body weight, aorta diameter, and L2 vertebral body length were assessed by calculation of Pearson correlation coefficients and 95% confidence intervals. Renal measurements were normalized to patient size by calculating renal length-to-aorta diameter and renal length-to-L2 vertebral body length ratios for comparison with previously published radiographic and ultrasonographic measurements.

RESULTS All kidneys were identified and measured on CT images by all observers. Intraobserver and interobserver agreement were excellent. Body weight, aorta diameter, and length of the L2 vertebral body were significantly correlated with renal length. Renal length-to-aorta diameter and renal length-to-L2 vertebral body length ratios (7.4 and 2.7, respectively) fell within the ranges of previously published values for these measurements.

CONCLUSIONS AND CLINICAL RELEVANCE As CT becomes more widely available in general practice, knowledge of typical renal measurements and anatomic ratios obtained with this modality in dogs may be useful. A prospective study with a larger population of dogs, ideally including formulation of a reference range, is needed.

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in Journal of the American Veterinary Medical Association


Objective—To evaluate the signalment, neurologic examination and imaging findings, and outcome in dogs treated medically or surgically for osseous-associated cervical spondylomyelopathy (OACSM).

Design—Retrospective case series.

Animals—27 client-owned dogs.

Procedures—Medical records for dogs with OACSM (diagnosis made in 2000 through 2012) were reviewed. Collected data included signalment, neurologic examination findings (graded from 0 [normal] to 5 [tetraplegia]), imaging findings, treatment, and outcome. From MRI and CT images, measurements were obtained for subjective grading of spinal cord compression.

Results—Among the 27 dogs, the median age was 2 years; there were 15 Great Danes, 3 Mastiffs, 3 Newfoundlands, and 6 other large-breed dogs. For medically treated dogs (n = 7), the median initial neurologic grade was 2; for surgically treated dogs (20), the median initial neurologic grade was 3. Magnetic resonance imaging revealed dorsolateral spinal cord compression in 22 dogs and lateral spinal cord compression in 5 dogs. Dogs with more severe compressions were slightly more likely to undergo surgical than medical treatment. Median survival time of medically treated dogs was 43 months, and that of surgically treated dogs was 60 months. Fifteen of 19 dogs treated surgically had improved neurologic grades at 4 to 8 weeks after surgery and had a good to excellent long-term outcome.

Conclusions and Clinical Relevance—Surgical treatment of dogs with OACSM resulted in neurologic improvement and was associated with a good long-term outcome. For dogs that received medical treatment, neurologic deterioration continued but some patients did well for several years. (J Am Vet Med Assoc 2014;244:1309–1318)

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in Journal of the American Veterinary Medical Association


To determine whether exogenous isobutane gas infused into the udders of dairy cattle could be detected ultrasonographically, and if so, what effects volume of gas infused and infusion pressure had on how long after infusion exogenous isobutane gas could be detected.


Randomized block design.


8 Holstein cows 28 to 32 days after parturition.


In each cow, 1 mammary gland was not treated and the other 3 received 1 of 3 treatments by means of intramammary infusion: low volume-high pressure, low volume-low pressure, and high volume-high pressure infusion of isobutane gas. Mammary glands were examined ultrasonographically 1 hour before and 1,3, 12, 24, 36, 48, 72, and 96 hours after treatment.


After intramammary infusion of isobutane gas, bright echoes and associated acoustic shadows were seen ultrasonographically; echoes were no longer seen 72 hours after gas infusion. Percentages of mammary glands in which bright echoes were detected were not significantly different among the 3 treatment groups at any time during the study.

Conclusions and Clinical Relevance

Results suggest that exogenous isobutane gas infused into the mammary glands to enhance the appearance of the udder of show dairy cattle can be readily detected by ultrasonography. (J Am Vet Med Assoc 1999;215:366–368)

Free access
in Journal of the American Veterinary Medical Association



To evaluate with CT the characteristics of brain tissue disruption and skull damage in cadaveric heads of adult horses caused by each of 6 firearm-ammunition combinations applied at a novel anatomic aiming point.


53 equine cadaveric heads.


Heads placed to simulate that of a standing horse were shot with 1 of 6 firearm-ammunition combinations applied at an aiming point along the external sagittal crest of the head where the 2 temporalis muscles form an inverted V. Firearm-ammunition combinations investigated included a .22-caliber long rifle pistol firing a 40-grain, plated lead, solid-core or hollow-point bullet (HPB); a semiautomatic 9-mm pistol firing a 115-grain, jacketed HPB; a semiautomatic .223-caliber carbine firing a 55-grain, jacketed HPB; a semiautomatic .45-caliber automatic Colt pistol firing a 230-grain, jacketed HPB; and a 12-gauge shotgun firing a 1-oz rifled slug. Additional heads placed in a simulated laterally recumbent position were shot with the semiautomatic 9-mm pistol–HPB combination. All heads underwent CT before and after being shot, and images were evaluated for projectile fragmentation, skull fracture, and cerebrum, cerebellum, and brainstem disruption.


Computed tomography revealed that all firearm-ammunition combinations caused disruption of the cerebrum, cerebellum, and brainstem that appeared sufficient to result in instantaneous death of a live horse. Hollow-point ammunition was as effective as solid-core ammunition with regard to brain tissue disruption. Brain tissue disruption was not affected by head positioning.


Results indicated that the examined firearm-ammunition combinations, when applied at a novel aiming point, appear to be reasonable options for euthanasia of horses.

Full access
in American Journal of Veterinary Research


Case Description—An approximately 8-month-old female Miniature Lop rabbit (Oryctolagus cuniculus) was evaluated because of an acute onset of progressive paraparesis.

Clinical Findings—The rabbit was ambulatory paraparetic, and results of neurologic examination were consistent with a myelopathy localizing to the T3-L3 spinal cord segments. Evaluation with CT myelography revealed focal extradural spinal cord compression bilaterally at the level of the articular process joints of T12-L1.

Treatment and Outcome—A Funkquist type A dorsal laminectomy was performed at T12-L1, and the vertebral column was stabilized with pins and polymethylmethacrylate-based cement. Multiple vertebral synovial cysts were confirmed on histologic evaluation of the surgically excised tissues. The rabbit was nonambulatory with severe paraparesis postoperatively and was ambulatory paraparetic at a recheck examination 7 weeks after surgery. Fourteen weeks after surgery, the rabbit appeared stronger; it walked and hopped slowly but still fell and dragged its hindquarters when moving faster. Thirty-seven weeks after surgery, the neurologic status was unchanged.

Clinical Relevance—Although thoracolumbar myelopathy in rabbits is commonly secondary to vertebral fracture, vertebral synovial cysts should be considered a differential diagnosis for rabbits with slowly progressive paraparesis. Decompressive surgery and stabilization can result in a good outcome for rabbits with this condition.

Full access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association