Comparison of fluoroscopic cardiovascular measurements from healthy dogs obtained at end-diastole and end-systole.

INTRODUCTION: Quantitative measurements are commonly implemented to objectively evaluate heart size in dogs. However, recent studies suggest that the phase of cardiac cycle can impact vertebral heart score, thereby potentially influencing clinical management. This study used fluoroscopy to assess the impact of the cardiac cycle on quantitative cardiovascular measurements in healthy dogs of various breeds. ANIMALS, MATERIALS, AND METHODS: This was a prospective study. Multiple cardiac and respiratory cycles were recorded fluoroscopically. Peak inspiratory end-systole and end-diastole frames were captured from 49 dogs in right lateral recumbency. Vertebral heart score (VHS), cardiothoracic ratio (CTR), vertebral left atrial size (VLAS), and caudal vena cava diameter ratio (CVCDR) measurements were performed. Mean cardiac measurements were compared between cardiac cycle phases, and the impact of body condition score (BCS), weight, thoracic conformation, sex, and age was evaluated. RESULTS: Cardiac cycle had a significant impact on VHS (mean difference: 0.36 ± 0.14 vertebral units between systole and diastole; p < 0.001) and CTR (mean difference: 2.2 ± 1.2% between systole and diastole; p < 0.001). Cardiac cycle had no significant impact on VLAS or CVCDR. Increasing BCS significantly increased variation between systole and diastole in CTR measurements (p = 0.024). CONCLUSIONS: The cardiac cycle has a significant effect on VHS and CTR but does not impact VLAS or CVCDR. These findings should be taken into consideration during clinical use of these measurements, especially if a patient is being monitored for cardiac changes over time via serial radiographs.

Association between environmental factors including second-hand smoke and primary lung cancer in dogs.

OBJECTIVES: To estimate prevalence of exposure to environmental tobacco smoke and other environmental toxins in dogs with primary lung tumours and to analyse association between exposure and lung tumour development. MATERIALS AND METHODS: In this case-control study, an owner survey was developed to collect data on patient characteristics, general health care and environmental exposures. Dogs diagnosed with primary lung carcinomas formed the Case group. Dogs diagnosed with mast cell tumours served as Control Group 1 and dogs diagnosed with neurologic disease served as Control Group 2. Associations between diagnosis of primary lung tumour and patient and environmental exposure variables were analysed using bivariate and multivariate statistical methods. RESULTS: A total of 1178 owner surveys were mailed and 470 surveys were returned and included in statistical analysis, including 135 Cases, 169 dogs in Control Group 1 and 166 dogs in Control Group 2. An association between exposure to second-hand smoke and prevalence of primary lung cancer was not identified in this study. CLINICAL SIGNIFICANCE: Second-hand smoke is associated with primary lung cancer in people but a definitive association has not been found in dogs. The results of this study suggest that tobacco smoke exposure may not be associated with primary lung cancer development in dogs but study limitations may have precluded detection of an association.

Fluoroscopic Estimation of Thoracic Dimensional Changes in Healthy Dogs.

BACKGROUND: Current methods available for assessing alterations in lung mechanics require sophisticated equipment and are of limited availability. A method that could assess lung area change with respiration might be a clinically useful surrogate for assessing lung compliance. OBJECTIVE: To use fluoroscopy to determine percent change in thoracic and lung areas in healthy dogs. ANIMALS: Forty-four client-owned dogs with no evidence of respiratory disease. METHODS: Prospective study. Resting respiration was recorded fluoroscopically, and peak inspiratory and expiratory frames were captured for 3 typical respiratory cycles. The number of intrathoracic pixels in the entire thoracic cavity was measured for both inspiration and expiration, and the average percent change in intrathoracic area was determined for each dog. This process was repeated by a hemithorax measurement of lung area that excluded the mediastinum and cardiac silhouette. Proposed reference ranges (and 95% confidence intervals [CI]) were computed by a nonparametric percentile distribution. RESULTS: Median percent change in thoracic dimension for the total thorax measurement was 12.5% (CI, 8.9-24.0%). Median percent change for the hemithorax measurement was significantly (P < 0.001) larger (20.8%, CI, 14.3-37.6%). Both measurement techniques were correlated with body weight but not with age, sex, thoracic conformation, body condition score (BCS), or breed. CONCLUSIONS AND CLINICAL IMPORTANCE: Fluoroscopy allows a noninvasive and repeatable measure of lung area changes during respiration that must be corrected for body weight. Additional studies in dogs with respiratory diseases are needed to determine its utility in detecting clinically useful alterations in lung area changes.

Ultrasound and computed tomography of the iliosacral lymphatic centre in dogs with anal sac gland carcinoma.

In this prospective study, we hypothesized that computed tomography (CT) would identify more normal and abnormal iliosacral lymph nodes (LNs) than abdominal ultrasound in dogs with anal sac gland carcinoma (ASGC). Twelve client-owned dogs with ASGC but without distant metastasis were enrolled. Abdominal ultrasound and contrast-enhanced CT scans of the abdomen were obtained. Iliosacral LNs were counted and assessed for location, laterality and size. Significantly (P < 0.00001) more iliosacral LNs were identified with CT (61) than ultrasound (30), including significantly (P = 0.00012) more medial iliac LNs with CT (33) than ultrasound (19). There was no difference in number of internal iliac LNs identified with CT versus ultrasound. Significantly (P = 0.000061) more sacral LNs were identified with CT (15) than ultrasound (0). Ultrasound identified slightly more (7) abnormal iliosacral LNs than CT (5). Contrast CT was able to identify more normal but not more abnormal LNs than ultrasound.

Perfusion and Volume Response of Canine Brain Tumors to Stereotactic Radiosurgery and Radiotherapy.

BACKGROUND: Stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) are highly conformal, high-dose radiation treatment techniques used to treat people and dogs with brain tumors. OBJECTIVES: To evaluate the response to SRS- and SRT-treated tumors using volume and perfusion variables and to measure the survival times of affected dogs. ANIMALS: Prospective study of 34 dogs with evidence of brain tumors undergoing stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT). METHODS: Computed tomography and MRI imaging were used to calculate tumor volume and perfusion at baseline, and at 3 months and 6 months after treatment. Survival analysis was performed to evaluate treatment efficacy. RESULTS: Mean tumor volume significantly declined from baseline to the first recheck by -0.826 cm(3) (95% CI: -1.165, -0.487) (P < .001); this reduction was maintained at the second recheck. Blood flow and blood volume declined significantly in the tumor after treatment. Median survival was 324 days (95% CI: 292.8, 419.4), and 4 dogs survived longer than 650 days. Neither actual tumor volume (hazard ratio = 1.21, P = .19) nor the change in tumor volume from the baseline (hazard ratio = 1.38, P = .12) significantly affected the hazard of death because of the tumor. CONCLUSIONS AND CLINICAL IMPORTANCE: Stereotactic radiosurgery and SRT are effective treatments for reducing tumor volume, blood flow, and blood volume. Treated dogs surviving for more than 1 year are more likely to die from other causes than of their primary brain tumor. SRS and SRT should be considered for noninvasive treatment of intracranial brain tumors.

Agreement Among Radiographs, Fluoroscopy and Bronchoscopy in Documentation of Airway Collapse in Dogs.

BACKGROUND: Airway collapse is a common finding in dogs with chronic cough, yet the diagnosis can be difficult to confirm without specialty equipment. HYPOTHESIS: Bronchoscopic documentation of tracheobronchial collapse will show better agreement with fluoroscopic imaging than with standard radiography. ANIMALS: Forty-two dogs prospectively evaluated for chronic cough. METHODS: In this prospective study, three-view thoracic radiographs were obtained followed by fluoroscopy during tidal respiration and fluoroscopy during induction of cough. Digital images were assessed for the presence or absence of collapse at the trachea and each lobar bronchus. Bronchoscopy was performed under general anesthesia for identification of tracheobronchial collapse at each lung segment. Agreement of imaging tests with bronchoscopy was evaluated along with sensitivity and specificity of imaging modalities as compared to bronchoscopy. RESULTS: Airway collapse was identified in 41/42 dogs via 1 or more testing modalities. Percent agreement between pairs of tests varied between 49 and 87% with poor-moderate agreement at most bronchial sites. Sensitivity for the detection of bronchoscopically identified collapse was highest for radiography at the trachea, left lobar bronchi, and the right middle bronchus, although specificity was relatively low. Detection of airway collapse was increased when fluoroscopy was performed after induction of cough compared to during tidal respiration. CONCLUSIONS: Radiography and fluoroscopy are complementary imaging techniques useful in the documentation of bronchial collapse in dogs. Confirming the presence or absence of tracheal or bronchial collapse can require multiple imaging modalities as well as bronchoscopy.

Bacterial urinary tract infections associated with transitional cell carcinoma in dogs.

BACKGROUND: Urinary tract infections (UTI) are believed to be common in dogs with transitional cell carcinoma (TCC), but incidence and contributing factors have not been reported. OBJECTIVES: To determine the frequency and bacterial agents associated with UTI in dogs with TCC and define contributing factors. ANIMALS: Eighty-five dogs with a history of urogenital TCC undergoing treatment with chemotherapy that had at least 1 urine culture performed. METHODS: Medical records and culture results were retrospectively reviewed and ultrasound images were reviewed when available. Clinical factors were evaluated statistically for association with positive culture. RESULTS: Fifty-five percent (47/85) of dogs had at least 1 positive culture during the course of treatment. Female dogs (80%, 40/50) were more likely than male dogs (29%, 10/35) to have at least 1 positive culture. Ultrasound examination determined that female dogs were more likely to have urethral (74%, 31/42) or trigonal tumor involvement (71%, 30/42) compared to male dogs (32%, 9/28 and 43%, 12/28, respectively). The most commonly isolated organisms were Staphylococcus spp. (23.9%, 29/121) and Escherichia coli (19.8%, 24/121). Dogs with urethral involvement of TCC were significantly more likely to have at least 1 positive culture than dogs without urethral involvement (75%, 30/40 versus 30%, 9/30). CONCLUSIONS: Urinary tract infection is common in dogs with TCC highlighting the importance of regular monitoring for bacterial cystitis in dogs with TCC. In addition, clinical factors such as tumor location and sex may be predictive of positive culture and can help clinicians assess the risk of UTI.

Vertebral heart scores in eight dog breeds.

The vertebral heart score (VHS) measurement is commonly used to provide a more objective measurement of cardiomegaly in canines. However, several studies have shown significant breed variations from the value previously established by Buchanan and Bücheler (9.7 ± 0.5). This study describes VHS measurements in Pug, Pomeranian, Yorkshire Terrier, Dachshund, Bulldog, Shih Tzu, Lhasa Apso, and Boston Terrier dog breeds. Dogs with two or three view thoracic radiographs, no subjective radiographic evidence of cardiomegaly, and no physical examination findings of heart murmurs or gallop rhythms were included in the study. The Pug, Pomeranian, Bulldog, and Boston Terrier groups were found to have a VHS significantly greater than 9.7 ± 0.5 (P < 0.00001, P = 0.0014, P < 0.0001, P < 0.00001, respectively). Body condition score (BCS) was found to have a significant effect on the VHS of Lhasa Apso group. Anomalous vertebrae in the thoracic column were associated with a significant increase in VHS of the Bulldog (P = 0.028) and Boston Terrier (P = 0.0004) groups. Thoracic depth to width ratio did not have a significant effect on VHS.

Bronchomalacia in dogs with myxomatous mitral valve degeneration.

BACKGROUND: Cough in the geriatric small breed dog with myxomatous mitral valve degeneration (MMVD), a large left atrium, and absence of heart failure often is attributed to compression of the left mainstem bronchus by the left atrium. Studies investigating this syndrome are lacking in dogs. HYPOTHESIS: Airway collapse is independent of left atrial enlargement. ANIMALS: A total of 16 dogs presenting with chronic cough in the absence of congestive heart failure. Group 1 dogs (n = 10) had moderate-to-severe left atrial enlargement based on an echocardiographically calculated left atrial:aortic surface area [LA:Ao(a)] > 6. Group 2 dogs (n = 6) had no to mild left atrial enlargement [LA:Ao(a) ≤ 6]. METHODS: Dogs were prospectively evaluated. CBC, biochemistry, urinalysis, cervical and thoracic radiographs, fluoroscopy, echocardiography, and bronchoscopy were performed. Bronchoscopic abnormalities were compared between groups using Fisher's Exact Test. P < .05 was considered significant. RESULTS: Fluoroscopy identified airway collapse in both groups. Bronchoscopic evidence of airway collapse >50% was observed in multiple bronchi with no difference between groups. All dogs had inflammation on airway cytology with respiratory infection in 1 dog in group 2. Left atrial size was interpreted radiographically as enlarged in 9 of 10 group 1 dog and in 2 of 6 group 2 dogs. VHS was above normal in both groups of dogs regardless of echocardiographic evidence of cardiomegaly. CONCLUSIONS: Results failed to identify an association between left atrial enlargement and airway collapse in dogs with MMVD, but did suggest that airway inflammation is common in dogs with airway collapse.

Salmon poisoning disease in dogs: 29 cases.

BACKGROUND: Salmon poisoning disease (SPD) is a trematode-borne disease of dogs caused by Neorickettsia helminthoeca. OBJECTIVES: To determine risk factors and spatial epidemiology of SPD in dogs from northern California; to describe the clinicopathologic, microbiologic, and imaging findings of SPD in these dogs; and to evaluate treatments and outcomes for SPD. ANIMALS: Twenty-nine dogs with SPD based on the finding of trematode ova in the feces, or organisms consistent with N. helminthoeca in specimens submitted for microscopic examination. METHODS: Information regarding signalment, fish exposure, clinical signs, diagnostic evaluation, treatments, and outcomes was obtained for each dog. Archived lymph node aspirates and histopathology specimens were subjected to polymerase chain reaction (PCR) testing for Neorickettsia spp. RESULTS: Labrador Retrievers and intact male dogs were overrepresented. Exposure locations were often distant from the dogs' residence. Some dogs had neurologic signs, including twitching and seizures. Dogs lacking peripheral lymphadenomegaly had abdominal lymphadenomegaly on ultrasound examination. A combination of centrifugation fecal flotation and sedimentation had greatest sensitivity for finding fluke ova. N. helminthoeca DNA was amplified by PCR from 4/10 dogs. Penicillins, cephalosporins, and chloramphenicol did not appear to be effective treatments. Mortality rate was 4/29 (14%). CONCLUSIONS AND CLINICAL IMPORTANCE: SPD should be suspected in dogs with inappetence, gastrointestinal, or neurologic signs, with or without fever or peripheral lymphadenomegaly in the appropriate geographical setting. Diagnosis is facilitated by a combination of fecal sedimentation and centrifugal flotation, abdominal ultrasonography, and PCR-based assays on lymphoid tissue. The treatment of choice is tetracycline antimicrobials.

Tracheal collapse and bronchomalacia in dogs: 58 cases (7 /2001-1 /2008).

BACKGROUND: Tracheobronchomalacia is diagnosed in people by documentation of a reduction in airway diameter during bronchoscopy. While tracheal collapse in the dog has been well described in the literature, little information is available on bronchomalacia in the dog. HYPOTHESES: Bronchomalacia is common in dogs with tracheal collapse, is associated with inflammatory airway disease, and is poorly documented radiographically. ANIMALS: One hundred and fifteen dogs admitted for evaluation for respiratory disease and examined by bronchoscopy. METHODS: Case-controlled, observational study. Dogs examined and having a bronchoscopic procedure performed by a single operator were separated into groups with and without visually identified airway collapse. Clinical parameters and bronchoalveolar lavage findings were compared between groups. Radiographs were reviewed in masked fashion to assess the sensitivity and specificity for detection of bronchomalacia. RESULTS: Tracheobronchomalacia was documented in 50% of dogs examined, with tracheal collapse in 21% and bronchomalacia in 47%. In dogs with bronchomalacia, collapse of the right middle (59%) and left cranial (52%) lung lobes was identified most commonly. Dogs with bronchomalacia were significantly more likely to display normal airway cytology and to have mitral regurgitation and cardiomegaly than dogs without airway collapse (P < .05). Radiographs were insensitive for detection of airway collapse. CONCLUSIONS AND CLINICAL IMPORTANCE: Bronchomalacia was identified more commonly than tracheal collapse in this population of dogs, and documentation required bronchoscopy. This study could not confirm a role for airway inflammation in bronchomalacia, and further studies are required to determine the role of cardiomegaly in the disorder.

Effects of body positioning on swallowing and esophageal transit in healthy dogs.

BACKGROUND: Contrast videofluoroscopy is the imaging technique of choice for evaluating dysphagic dogs. In people, body position alters the outcome of videofluoroscopic assessment of swallowing. HYPOTHESIS/OBJECTIVE: That esophageal transit in dogs, as measured by a barium esophagram, is not affected by body position. ANIMALS: Healthy dogs (n=15). METHODS: Interventional, experimental study. A restraint device was built to facilitate imaging of dogs in sternal recumbency. Each dog underwent videofluoroscopy during swallowing of liquid barium and barium-soaked kibble in sternal and lateral recumbency. Timing of swallowing, pharyngeal constriction ratio, esophageal transit time, and number of esophageal peristaltic waves were compared among body positions. RESULTS: Transit time in the cervical esophagus (cm/s) was significantly delayed when dogs were in lateral recumbency for both liquid (2.58+/-1.98 versus 7.23+/-3.11; P=.001) and kibble (4.44+/-2.02 versus 8.92+/-4.80; P=.002). In lateral recumbency, 52+/-22% of liquid and 73+/-23% of kibble swallows stimulated primary esophageal peristalsis. In sternal recumbency, 77+/-24% of liquid (P=.01 versus lateral) and 89+/-16% of kibble (P=.01 versus lateral) swallows stimulated primary esophageal peristalsis. Other variables were not significantly different. CONCLUSIONS AND CLINICAL IMPORTANCE: Lateral body positioning significantly increases cervical esophageal transit time and affects the type of peristaltic wave generated by a swallow.

Canine intraspinal meningiomas: imaging features, histopathologic classification, and long-term outcome in 34 dogs.

BACKGROUND: Meningioma is the most common primary intraspinal nervous system tumor in dogs. Clinical findings, clinicopathologic data, and treatment of these tumors have been reported sporadically, but little information is available regarding cerebrospinal fluid (CSF) analysis, histologic tumor grade, or efficacy of radiation therapy as an adjunct to cytoreductive surgery. ANIMALS: Dogs with histologically confirmed intraspinal meningiomas (n = 34). METHODS: A retrospective study of dogs with intraspinal meningiomas between 1984 and 2006 was carried out. Signalment, historical information, physical examination, clinicopathologic data, radiation therapy protocols, surgery reports, and all available images were reviewed. All tumors were histologically classified and graded as defined by the international World Health Organization classification scheme for central nervous system tumors. RESULTS: Intraspinal mengiomas in dogs are most common in the cervical spinal cord but can be found throughout the neuraxis. Location is correlated with histologic grade, with grade I tumors more likely to be in the cervical region than grade II tumors. Myelography generally shows an intradural extramedullary compressive lesion. On magnetic resonance imaging, the masses are strongly and uniformly contrast enhancing and a dural tail often is present. CSF analysis usually shows increased protein concentration with mild to moderate mixed pleocytosis. Surgical resection is an effective means of improving neurologic status, and adjunctive radiation therapy may lead to an improved outcome. CONCLUSIONS AND CLINICAL IMPORTANCE: Biopsy is necessary for definitive diagnosis, but imaging and CSF analysis can suggest a diagnosis of meningioma. Treatment of meningiomas with surgery and radiation therapy can result in a fair to excellent prognosis.

Management of carpal tunnel syndrome in renal dialysis patients using an extended carpal tunnel release procedure.

BACKGROUND: Chronic dialysis patients are susceptible to median nerve compression. This may be due to oedema or vascular insufficiency related to a dialysis shunt or fistula. Patients with renal failure may also develop amyloid disease. Amyloid infiltration of the synovium within the carpal canal may be a contributing factor to the nerve compression. Traditional carpal tunnel release, although simple to perform, is associated with a much higher recurrence rate in this group than in nonrenal patients. Our aim was to modify the carpal tunnel release procedure and prevent these recurrences. METHODS: A retrospective review of 24 extended carpal tunnel decompressions in 19 dialysis patients was performed, with reference to patient records. The surgical technique is detailed and the clinical results analysed. RESULTS: All patients noted an early and sustained improvement in symptoms; those patients with established sensory or motor signs had poorer results following surgery. There were no instances of recurrence of nerve compression during this follow-up period, range 2-6 years. CONCLUSIONS: Carpal tunnel decompression enhances hand function and quality of life in this group.

Trends in veterinary cancer imaging.

With the recent advances in diagnostic imaging technology, cancer imaging in veterinary medicine has become more specific for disease diagnosis, more accurate for determining tumour margins and more sensitive for detecting metastatic disease. Ultrasound provides highly detailed images of parenchymal masses and infiltrative lesions while providing a means for aspiration or biopsy using real-time image guidance. Computed tomography and magnetic resonance-imaging techniques provide exquisite anatomical resolution that improves diagnostic accuracy, provides an accurate means of radiation or surgical treatment planning and a quantitative means for monitoring response to therapy. In addition to traditional anatomic imaging, new techniques are being developed for estimating functional parameters such as tumour perfusion, cell metabolism and gene expression. While conventional planar scintigraphy has been available for some time, newer nuclear imaging modalities such as positron emission tomography promise to further improve the accuracy of initial tumour diagnosis and staging and determination of response to therapy. Although many of these functional techniques are not yet clinically available, it is highly likely that some will be integrated into routine clinical practice in the near future.

Percutaneous ultrasonographically guided radiofrequency heat ablation for treatment of primary hyperparathyroidism in dogs.

OBJECTIVE: To evaluate the efficacy and safety of ultrasonographically guided radiofrequency heat ablation of parathyroid masses in dogs with primary hyperparathyroidism. DESIGN: Clinical trial. ANIMALS: 11 dogs. PROCEDURE: In all dogs, either 1 or 2 parathyroid masses were evident ultrasonographically. Dogs were anesthetized, and a 20-gauge over-the-needle catheter was directed into the parathyroid mass via ultrasonographic guidance. Radiofrequency heat was applied to the stylet of the catheter until there was sonographically apparent change to the entire parenchyma of the mass. Serum total and ionized calcium and parathyroid hormone concentrations were monitored daily for 5 days after the ablation procedure and again at 1, 2, and 3-month intervals, if possible. Dogs were monitored for adverse effects. RESULTS: One treatment was required in 6 dogs, 2 treatments were required in 2 dogs, and treatment was unsuccessful in 3 dogs. Serum total and ionized calcium concentrations were within reference ranges within 2 days of the last procedure in all 8 successfully treated dogs. Serum parathyroid hormone concentration was decreased 24 hours after treatment in all 8 dogs. Hypocalcemia developed in 5 of the 8 successfully treated dogs, all of which required treatment. One dog had a transient voice change. Other adverse effects were not reported. CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasonographically guided radiofrequency heat ablation of parathyroid masses is a safe and effective alternative to surgery in dogs with primary hyperparathyroidism.

Evaluation of interoperator variance in shunt fraction calculation after transcolonic scintigraphy for diagnosis of portosystemic shunts in dogs and cats.

OBJECTIVE: To determine interoperator variance in shunt fraction calculation. DESIGN: Case series. SAMPLE POPULATION: 101 transrectal portoscintigraphic studies. PROCEDURE: Results of dynamic portoscintigraphic studies were reviewed by 4 radiologists without knowledge of signalment, history, or medical profile. Results were judged to be negative or positive on the basis of the dynamic scan. Composite images were formulated, and hand-drawn regions of interest were determined for the heart and liver. Time-activity curves were generated, time-zero points were selected, curves were integrated during a 10-second interval, and shunt fractions were calculated. RESULTS: Radiologists were in agreement regarding positive versus negative results for 99 of 101 studies. Interoperator variance in shunt fraction calculation ranged from 0.4 to 59.6%. For 51 studies with positive results, variance ranged from 2.5 to 59.6% (mean +/- SD, 22.8 +/- 14.5%); differences among reviewers were significant. For 48 studies with negative results, variance in shunt fraction ranged from 0.4 to 25.9% (mean, 5.3 +/- 5.8%); significant differences among reviewers were not detected. Shunt fraction calculations were not exactly reproducible among radiologists in 94 and 100% of studies with negative or positive results, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that shunt fraction values are not reproducible among operators. Range in variability was greater in studies with positive results. This factor may be of particular clinical importance in reassessment of patients after incomplete shunt ligation.

Quantitative videofluoroscopic evaluation of pharyngeal function in the dog.

Videofluoroscopic evaluation of both liquid barium and barium soaked kibble was performed in 11 adult, clinically normal dogs of varying breeds. Each examination was digitized and evaluated frame by frame to establish the normal timing sequence of the pharyngeal phase of swallowing. Closure of the epiglottis was considered the onset of swallowing. The time to each of the following events was recorded: (1) Maximum pharyngeal contraction, (2) Opening of the epiglottis, (3) Opening of the cranial esophageal sphincter, and (4) Closure of the cranial esophageal sphincter. These values were found to be consistent both intra and interpatient. Retrospective analysis of 3 videofluoroscopic examinations from dogs that met the subjective criteria defining cricopharyngeal achalasia was then performed. A statistically significant delay in the time to opening and closure of the cranial esophageal sphincter was found employing both liquid barium and barium soaked kibble in the dogs with cricopharyngeal achalasia.

Comparison of two surgical techniques for renal transplantation in cats.

OBJECTIVE: To compare two surgical techniques for renal transplantation in cats with respect to graft warm ischemia time, total surgical time, operative and postoperative complications, and return to normal renal function based on measurement of plasma creatinine concentrations. STUDY DESIGN: Research study using normal cats. ANIMALS OR SAMPLE POPULATION: Fourteen adult, feline leukemia virus and feline immunodeficiency virus (FELV/FIV) negative, neutered male and spayed female cats. MATERIALS AND METHODS: Fourteen cats underwent heterotopic renal isograft transplantation with nephrectomy of the contralateral kidney. Renal arterial end-to-end anastomosis to the external iliac artery was performed in eight cats and renal arterial end-to-side anastomosis to the aorta was performed in six cats. Cats were monitored for 14 days after surgery. Renal function was evaluated by daily measurement of plasma creatinine concentrations. The cats' health was assessed by the daily recording of body weight, rectal temperature, postoperative complications, urine production, appetite, packed red blood cell volume, and total serum protein. Ultrasonographic assessment of the isograft was performed every third day. Animals were euthanatized or adopted 14 days after surgery and histopathologic analysis of biopsies or whole isograft tissues was performed. RESULTS: Nine of fourteen cats survived the 14-day study period. Although not statistically significant, mean total surgical time and graft warm ischemia time was shorter for the arterial end-to-side anastomosis. Mean daily plasma creatinine concentrations were not significantly different between the two groups. Five of eight cats (62%) undergoing the arterial end-to-end technique developed neuropraxia and lameness of the ipsilateral pelvic limb. Five cats died or were euthanatized because of other complications. CONCLUSIONS AND CLINICAL RELEVANCE: The arterial end-to-side technique appears to be the better method for renal transplantation in cats. Shorter graft warm ischemia and total surgical times, absence of pelvic limb complications, and an adequate return to normal renal function were associated with this technique.