Daniel A. Feeney

Clinical, ultrasonographic, and laboratory findings associated with gallbladder disease and rupture in dogs: 45 cases (1997-2007).

OBJECTIVE To identify clinical, laboratory, and ultrasonographic characteristics associated with gallbladder disease and rupture in dogs. DESIGN Retrospective case series. ANIMALS 45 client-owned dogs. PROCEDURES Medical records of dogs with histologically confirmed gallbladder disease that had ultrasonographic evaluation were reviewed. Signalment, history, clinical signs, laboratory values, bacteriologic culture of bile, gallbladder status at surgery or necropsy (intact vs ruptured), histopathologic findings, radiographic findings, ultrasonographic findings, and outcome were analyzed. RESULTS The most common ultrasonographic findings were echogenic peritoneal fluid, thickened or laminated gallbladder wall, and echogenic reaction in the gallbladder fossa. Eighteen of 45 (40%) dogs had gallbladder rupture. Rupture was associated with histologic evidence of gallbladder necrosis, decreased serosal detail radiographically, and pericholecystic echogenic reaction, pericholecystic echogenic fluid, and generalized echogenic abdominal effusion ultrasonographically. Twenty-one of 45 (47%) dogs had mucocele, and 9 (43%) of those had gallbladder rupture. Eleven of 40 dogs had positive results of bacteriologic culture, and 5 of those had gallbladder rupture. Only 2 dogs had concurrent positive results of bacterial bile culture and gallbladder mucocele. Survival rate was 86% and not significantly related to presurgical bile leakage, positive results of bacterial culture, or mucocele. CONCLUSIONS AND CLINICAL RELEVANCE Ultrasonographic findings of pericholecystic reaction, localized or generalized echogenic peritoneal fluid, or decreased radiographic peritoneal detail should raise the index of suspicion for gallbladder rupture. Mucocele or bacterial gallbladder infection was the most common concurrent finding in dogs with gallbladder rupture.

Effects of high-dose and low-dose preoperative irradiation on low anterior anastomoses in dogs

Twenty mongrel dogs underwent preoperative irradiation to the colon and rectum, receiving 4000 rads according to the Nominal Standard Dose Equation. Each dog then underwent anterior resection of the rectosigmoid, and reconstructive technique was randomized into two groups consisting of either handsewn or EEA-stapled anastomoses. Anastomoses were examined digitally and radiographically at the time of surgery and on the seventh postoperative day. There were four radiographic leaks among the handsewn anastomoses, but only one was clinically significant and associated with peritonitis. There were no leaks among the ten EEA-stapled anastomoses. The data suggest that low anterior resection and anastomosis can be done safely after 4000 rad irradiation and that the EEA-stapled anastomosis may be preferable.

Canine gastric neoplasia: utility of ultrasonography in diagnosis.

The utility of ultrasonography in the diagnosis of canine gastric neoplasia was evaluated prospectively in a series of six cases subsequently confirmed as having adenocarcinoma by cytological or histological examination or both. Gastric neoplasia was associated with mural thickening with loss of normal wall sonographic layers and decreased or absent local motility. Sonographic findings were consistent with tumor localization obtained by other diagnostic methods employed. Ultrasonographic-guided, percutaneous, fine-needle aspirations biopsies were successful in two of the three cases in which they were performed. Ultrasonography appears useful in the diagnostic of canine gastric neoplasia.

Efficacy of radioprotective agents in preventing small and large bowel radiation injury

PURPOSE: A variety of adjuvant treatments and cytoprotective agents have been proposed to lessen the toxicity of radiation therapy. The following study was designed to evaluate the benefit of six agents or combinations using anastomotic bursting strength as a measure of transmural radiation injury. METHODS: The 40-Gy study consisted of the following. Seventy-two male Sprague-Dawley rats were divided into eight equal groups: nonradiated control, radiated untreated control, and six radiated treated groups. The radioprotective treatments included ribose-cysteine (RibCys), WR-2721, glutamine, vitamin E, MgCl2/adenosine triphosphate, and RibCys/glutamine in combination. Radiated animals received 40 Gy to the abdomen. Two weeks after radiation, all animals underwent small bowel and colonic resection with primary anastomosis. Animals were sacrificed one week postoperatively, at which time anastomoses were evaluated and bursting strengths determined. The 70-Gy study consisted of the following. The same protocol was repeated for five groups of nine rats divided into nonradiated, radiated untreated, and three radiated treated groups receiving RibCys (8 mmol/kg), RibCys (20 mmol/kg), and WR-2721. All radiated animals received 70-Gy doses. RESULTS: In the 40-Gy group, there were 10 radiation-related deaths and 6 anastomotic leaks among 70 rats studied. None of the differences between groups were significant. Nonradiated control group small bowel and large bowel anastomotic bursting pressures were significantly elevated compared with all radiated groups. Compared with radiated controls, there were significant improvements in small bowel bursting strength in the RibCys, WR-2721, RibCys-glutamine, and vitamin E groups and significant improvement in colonic bursting strength in MgCl2/adenosine triphosphate, WR-2721, and RibCys groups. In the 70-Gy group, all nine nonradiated control rats survived. All eight untreated radiated control rats died, four of eight WR-2721 animals died (P=0.03), all RibCys (8 mmol/kg) animals died (P=0.03), and three of nine treated with RibCys (20 mmol/kg) survived (P=0.08). CONCLUSIONS: WR-2721 and RibCys gave consistent protection against large and small bowel radiation injury. The lower incidence of treatment-related toxicity and potentially equal or greater radioprotective effects may make RibCys more clinically useful than WR-2721.

Canine intracranial gliomas: Relationship between magnetic resonance imaging criteria and tumor type and grade

Limited information is available to assist in the ante-mortem prediction of tumor type and grade for dogs with primary brain tumors. The objective of the current study was to identify magnetic resonance imaging (MRI) criteria related to the histopathological type and grade of gliomas in dogs. A convenience sample utilizing client-owned dogs (n=31) with gliomas was used. Medical records of dogs with intracranial lesions admitted to two veterinary referral hospitals were reviewed and cases with a complete brain MRI and definitive histopathological diagnosis were retrieved for analysis. Each MRI was independently interpreted by five investigators who were provided with standardized grading instructions and remained blinded to the histopathological diagnosis. Mild to no contrast enhancement, an absence of cystic structures (single or multiple), and a tumor location other than the thalamo-capsular region were independently associated with grade II tumors compared to higher grade tumors. In comparison to oligodendrogliomas, astrocytomas were independently associated with the presence of moderate to extensive peri-tumoral edema, a lack of ventricular distortion, and an isointense or hyper-intense T1W-signal. When clinical and MRI features indicate that a glioma is most likely, certain MRI criteria can be used to inform the level of suspicion for low tumor grade, particularly poor contrast enhancement. Information obtained from the MRI of such dogs can also assist in predicting an astrocytoma or an oligodendroglioma, but no single imaging characteristic allows for a particular tumor type to be ruled out.

Effects of low-dose preoperative irradiation on low anterior anastomosis in dogs.

Twenty mongrel dogs underwent preoperative radiation therapy to the colon and rectum using the Nominal Standard Dose Equation to simulate treatment with 2000 rads. Each dog then underwent anterior resection of the rectosigmoid, and reconstruction was randomized into two groups consisting of either handsewn or EEA-stapled anastomoses. Anastomoses were examined digitally and radiographically on the day of surgery and on the seventh postoperative day. There were three radiographic leaks among the ten dogs having the handsewn anastomoses and one radiographic leak among the ten dogs having the EEA-stapled anastomoses. There was one clinically significant leak which occurred in a dog having an EEA-stapled anastomosis and was associated with peritonitis and death. The overall leak rate was 30 per cent among dogs having handsewn anastomoses and 20 per cent among dogs with stapled anastomoses. The data suggest that an anterior resection in low colorectal anastomosis can be done safely after low-dose radiation using either handsewn or stapling techniques.

Utility of diagnostic tests for and medical treatment of pulmonary blastomycosis in dogs: 125 cases (1989-2006)

OBJECTIVE To compare results of the most common diagnostic tests for pulmonary blastomycosis in dogs, identify factors associated with outcome, and determine response to various antifungal treatment protocols. DESIGN Retrospective case series. ANIMALS 125 dogs with pulmonary blastomycosis. PROCEDURES Medical records were reviewed, and information was obtained regarding diagnostic methods, results of routine laboratory testing, and radiographic response to antifungal treatment. RESULTS 79 dogs survived, 38 died, and 8 were euthanized. Transthoracic fine-needle aspiration and transtracheal lavage were the most common diagnostic methods. Results of an agar gel immunodiffusion test for antibodies against Blastomyces dermatitidis were negative in 12 of 24 (50%) dogs. Only 3 of 94 (3.2%) dogs in which cytologic or histologic examination or bacterial culture of pulmonary samples were performed had any evidence of concurrent bacterial infection. The half-time for radiographic resolution of pulmonary infiltrates did not vary significantly with antifungal treatment, and use of a loading dosage of itraconazole was not associated with significant improvements in outcome or time to disease resolution. Dogs that died had a higher number of band neutrophils at initial examination, compared with those that survived. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the agar gel immunodiffusion test should not be used as the sole diagnostic test for pulmonary blastomycosis in dogs, that concurrent bacterial pneumonia was uncommon in dogs with pulmonary blastomycosis, and that the rate with which pulmonary infiltrates resolved did not vary significantly among antifungal treatments.

Diagnostic Imaging of the Male Canine Reproductive Organs: Methods and Limitations

Survey radiographic, contrast radiographic, and ultrasonographic techniques for evaluation of the male canine reproductive organs are reviewed. The applications and limitations of these technique as they apply to reproductive diseases involving the prostate gland and testicles are illustrated.

Two-dimensional, gray-scale ultrasonography. Applications in canine prostatic disease.

The technique of and general appearance of suprapubic gray-scale prostatic ultrasonography in the dog are described. Using case examples, the various spontaneous diseases of the canine prostate are described and compared to the defined normal appearance of the prostate. An integrated approach to imaging the canine prostate gland is advocated and includes radiographic techniques, specifically distension retrograde urethrocystography. A clinically relevant classification scheme for use with microbiologic, cytologic, and imaging techniques is proposed.

Accuracy of US-guided FNA of focal liver lesions in dogs: 140 cases (2005-2008)

Medical records from dogs having abdominal ultrasound (US) performed between March 2005 and October 2008 were reviewed for detection of focal liver lesions (FLL) with both cytologic and histologic sampling. Samples were classified as to either the presence or absence of major categories of pathologic processes, including malignant neoplasia, inflammation, hyperplasia/benign neoplasia, vacuolar change, extramedullary hematopoeisis, cholestasis, necrosis, and no microscopic abnormalities. Evaluation of selection bias was performed by review of the relative distribution of cytologic diagnoses for cases with histology compared with cases excluded from the comparison analysis because histology results were not available. Cytology had the highest sensitivity for vacuolar change (57.9%), followed by neoplasia (52.0%). Cytology had the highest positive predictive value (PPV) for neoplasia (86.7%) followed by vacuolar change (51.6%). Cytology had lower sensitivity and PPVs for inflammation, necrosis, and hyperplasia. The ability of cytology to characterize disease in canine FLL varies by pathologic process. Clinicians can have a high degree of confidence when a cytologic diagnosis of neoplasia is given; however, cytology is less reliable for excluding the potential for neoplasia. Cytology has a low sensitivity and PPV for inflammation and a limited diagnostic performance for the diagnosis of vacuolar change.