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121.
Reasons for performing study: Arthroscopy of the fetlock joints is a routine surgical procedure in the horse. It is unclear how much of the articular surface of the condyles of the metacarpal (MCIII)/metatarsal (MTIII) bone can be visualised using either the dorsal or palmar/plantar arthroscopic approach. Objectives: To investigate which part of the articular surface of the MCIII/MTIII condyles of the fetlock joints can be evaluated arthroscopically using: 1) dorsal approach in combination with flexion; 2) standard palmar/plantar approach; or 3) additional portal at the base of the sesamoid bone with joint extension. Methods: All 3 arthroscopic approaches were performed on 20 fore‐ and 20 hindlimbs of 14 cadavers. For each approach, a curette was inserted ipsilaterally to create a lesion at the most distal part of the condyle that could be seen. After disarticulation and placement of a nail in each lesion, the maximally reachable angle was calculated on a perfect lateromedial radiograph. The 0° angle was determined as the distal crossing of the best fitting circle around the condyle with a line parallel to the dorsal MCIII/MTIII bone running through the circle centre (positive angle dorsal to 0°, negative palmar/plantar to 0°). Results: Using the dorsal approach with flexion, a significantly larger area of visualisation was present in the hind‐ (?23.4°) compared to the forelimb (+2.7°). Using the palmar/plantar approach (fore: ?60.4°; hind: ?70.7°) and the approach at the base of the sesamoid bone (fore: ?36.3°; hind: ?47.6°) more cartilage could be seen in the fore‐ compared to the hindlimb. When combining the 3 approaches, the remaining nonvisible part measured 38.9° in the fore‐ and 24.2° in the hindlimb, both located palmaro/plantarodistally. Conclusions: The use of dorsal and palmar/plantar arthroscopic approaches in combination with flexion and extension of the fetlock joint allows visualisation of the majority of the cartilage of the MCIII/MTIII condyles. The nonvisible section is smaller in the hindlimb compared to the forelimb. Potential relevance: Knowledge of the specific areas of visualisation of the condyles on arthroscopy is important for both diagnostic and therapeutic planning of fetlock disorders.  相似文献   
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Background: Eosinophilic inflammation of the gastrointestinal tract of dogs occurs in numerous disorders, typically resulting in diffuse intestinal thickening. Rarely, eosinophilic masses have been reported.
Objective: Describe a series of dogs with 1 or more idiopathic eosinophilic gastrointestinal masses (IEGM) to better characterize the clinical features, treatment, and prognosis.
Animals: Seven dogs with 1 or more gastrointestinal masses composed primarily of eosinophilic infiltrates for which no underlying cause was found.
Methods: Retrospective case series.
Results: Rottweilers and purebred, large breed dogs predominated. Dogs were middle-aged and typically had chronic signs of upper or lower gastrointestinal disease. Decreased appetite, vomiting, and evidence of gastrointestinal hemorrhage were present in the majority of cases. An abdominal or rectal mass was frequently noted on physical examination. Common laboratory abnormalities included peripheral eosinophilia, mature neutrophilia, hypoproteinemia, and hypocholesterolemia. The masses were histologically composed of moderate to severe eosinophilic infiltrates, which were often transmural and accompanied by fibrosis. All dogs treated with surgery alone died of complications of their disease. Treatment with corticosteroids and ivermectin improved clinical signs, caused resolution of eosinophilic infiltrates, and prolonged survival in most dogs treated medically.
Conclusions and Clinical Importance: These findings suggest that the prognosis for dogs with IEGM may be good when recognized and managed appropriately. When surgery is performed, medical treatment should also be added.  相似文献   
124.
Background: Transcatheter atrial septal defect (ASD) closure in the dog was first reported in 2005.
Objectives: Describe the technique and both short- and mid-term outcome of transcatheter ASD closure with the Amplatzer® atrial septal occluder (ASO).
Animals: Thirteen client-owned dogs with ASD.
Methods: Records of the initial 13 dogs in which transcatheter ASD closure was attempted at Texas A&M University were reviewed.
Results: All dogs had hemodynamically relevant septum secundum ASD. Two dogs had concurrent congenital abnormalities. ASOs were deployed in 13 dogs and released in 12. Eleven were released by a right jugular approach and 1 by a transatrial approach through a right lateral thoracotomy. Transthoracic echocardiographic estimates of ASD size were 14.0 ± 5.4 mm (mean ± 1 standard deviation) with a range of 7–22 mm. Accidental right atrial release occurred in 1 dog and embolization after release occurred in 2 dogs. Transcatheter ASD closure was successful in 10 dogs. Transthoracic color Doppler echocardiography the day after ASD closure indicated complete occlusion in 5 dogs, trivial to mild residual shunting in 4 dogs, and moderate residual shunting in 1 dog. Follow-up echocardiograms (mean of 12.4 ± 7.4 months postprocedure) were available for 9 dogs. There was no residual ASD shunting in 6 dogs. In 3 of the 5 dogs with postoperative residual shunting it was judged to be decreased and hemodynamically unimportant relative to the dogs' postoperative evaluations. The mean length of event-free survival in the 10 dogs that underwent successful transcatheter ASD closure was 22.2 ± 10.2 months.  相似文献   
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OBJECTIVE: To evaluate efficacy of intra-articular injection of gadolinium tetra- azacyclododecane tetraacetic acid (gadolinium-DOTA) for delineating fragmented medial coronoid processes (FMCP) and lesions on the medial aspect of the humeral condyle (MAHC). SAMPLE POPULATION: 14 cubital joints in 9 dogs. PROCEDURE: Magnetic resonance imaging (MRI) was performed with and without intra-articular injection of a solution of 2 mmol of gadolinium-DOTA/L. Arthrographic images obtained after injection of contrast medium were compared with those obtained without contrast medium. Evidence of contrast medium around or in the medial coronoid process and infiltration of contrast medium in subchondral bone lesions was recorded. Twenty-four hours after imaging, arthroscopy was performed, and lesions detected were correlated with results of MRI. RESULTS: An abnormal coronoid process was diagnosed in 13 of 14 joints. A fragmented process (free) was seen in 7 of 14 joints; nondisplaced mineralized medial (in situ) coronoid processes were evident in 4 joints; and nondisplaced unmineralized medial coronoid processes were evident in 2 joints. Lesions on the MAHC were diagnosed in 4 of 12 joints. In 5 joints, a hyperintense signal resulted from contrast medium that infiltrated between the fragmented process and ulna. In 2 joints, contrast medium did not infiltrate completely around the process and was stopped by an isointense structure (ie, abnormal cartilage). Subchondral bone lesions were enhanced by use of contrast medium. CONCLUSION AND CLINICAL RELEVANCE: Use of arthrography enabled us to identify FMCP easily, but did not provide important additional information about changes on the medial coronoid process, compared with MRI performed without contrast medium.  相似文献   
127.
OBJECTIVES: To evaluate and compare methods for DNA extraction from formalin-fixed, paraffin-embedded tissues and methods for detection of Mycobacterium avium subsp paratuberculosis by IS900 PCR for confirmation of Johne's disease in ruminants. DESIGN: A laboratory study. PROCEDURE: Three methods of DNA extraction of differing complexity and two PCR protocols using different pairs of IS900 primers were compared. Sensitivity and specificity were assessed using samples from ruminants with and without histological evidence of Johne's disease. RESULTS: The simplest method of DNA extraction, which involved two cycles of boiling and freezing followed by centrifugation, gave more consistent results than two methods that required solvent extraction of paraffin, proteinase digestion and DNA purification. The sensitivity of detection of M avium subsp paratuberculosis in paraffin blocks stored for 1 to 6 years from 34 cases of Johne's disease in sheep, cattle and goats was 88% for a 229 bp IS900 PCR assay and 71% for a 413 bp assay, using the detection of acid-fast bacilli by Ziehl Neelsen staining of histological sections from the same blocks as the gold standard test. PCR results correlated with the abundance of acid-fast organisms in the tissues. No false positive reactions were detected. CONCLUSION: PCR for identification of M avium subsp paratuberculosis in formalin-fixed, paraffin-embedded intestinal tissues from ruminants is a rapid and useful method. A simple method of sample preparation is effective. Amplification of short fragments of IS900 is more effective than amplification of longer fragments.  相似文献   
128.
OBJECTIVE: To present details of an unusual case of caudal vena caval obstruction and its management in a cat. STUDY DESIGN: Clinical case report. STUDY POPULATION: A 15 month old male castrated domestic shorthaired cat. RESULTS: The diagnostic evaluation included the use of digital subtraction angiography and ultrasonography to locate the caudal vena caval obstruction. Treatment initially involved puncture and balloon dilation of the obstructed area of the cava. After reobstruction, the stenotic area was redilated and stented. The cat was euthanatized 4 weeks later because of vomiting, anorexia, and abnormal behavior, presumed to be associated with liver disease. CONCLUSION AND CLINICAL RELEVANCE: Interventional radiography provided a minimally invasive way to manage this unusual vascular anomaly.  相似文献   
129.
Computed tomography (CT) was performed on 36 dogs with nasal aspergillosis to assess whether this imaging technique can be used to predict the success of a noninvasive intranasal infusion of enilconazole. A CT score based on the severity of the disease was given to each dog, prior to treatment, by dividing the nasal cavities and frontal sinuses into 8 anatomical regions. After therapy, the dogs were classified into 2 response groups (success group: dogs cured after 1 treatment; failure group: dogs needing more than 1 treatment or with treatment failure). No significant relationship on the logistic scale was found between the CT score and the response to treatment. High sensitivity (treatment failures correctly predicted) and specificity (treatment successes correctly predicted) could not be obtained at the same time, whatever the cut-off value chosen. The results of this study suggest that CT cannot predict the therapeutic success of nasal aspergillosis in dogs treated with a 1-hour infusion of enilconazole. However, dogs with a low score seem to be good candidates to respond after 1 treatment.  相似文献   
130.
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