Evaluation of two nephrocystostomy techniques for ureteral bypass in cats.

OBJECTIVE: To describe two techniques for nephrocystostomy (NCT) in cats. STUDY DESIGN: Experimental study. ANIMALS: Twelve, adult, purpose-bred, cats. METHODS: A simple NCT (n = 3) or bladder cuff NCT (n = 9) was performed in the right or left kidneys. For simple NCT, an 8F catheter was placed through the caudal pole into the renal pelvis and the bladder was sutured around the catheter. For bladder cuff NCT, a 6 mm defect was removed from the caudal pole and a cuff of bladder mucosa was advanced and sutured into the renal pelvis. A 10F catheter was placed through the defect into the renal pelvis and the bladder wall was sutured around the catheter. Catheters were removed 41-118 days post-surgery. Computed tomography (CT) was performed 25 days after catheter removal for the simple NCT and 30 (n = 6) and 90 (n = 3) days after catheter removal for bladder cuff NCT. Histological evaluation of the nephrocystostomy site was performed. RESULTS: All simple NCTs became obstructed after catheter removal. All bladder cuff NCTs were patent, and CT revealed contrast flow into the bladder. Hematuria, clot-associated urethral obstruction, catheter dislodgement, and bladder infection occurred variably after surgery. Histological findings consisted of smooth epithelialization of the NCT and degenerative changes in the caudal pole of the kidney. CONCLUSION: Bladder cuff NCT was feasible in normal cats and remained patent for 90 days. Methods to limit nephrostomy track hemorrhage should be investigated. Degenerative changes may be related to vascular impairment from the bladder cuff sutures. CLINICAL SIGNIFICANCE: Complete ureteral bypass was possible in cats using only native tissues.

MRI of the live fish brain at 3 Tesla: Feasibility, technique and interspecies anatomic variations.

Advances in aquatic animal medicine and continued growth of the fish hobbyist and aquaculture communities have led to a developing interest in antemortem diagnostic imaging of aquatic species. The aims of this prospective, pilot study were to determine whether advanced neuroimaging can be safely achieved in live fish using clinically available equipment, to optimize imaging parameters, and to develop a comparative MRI atlas of a few fish species of economic or research value. Two each of channel catfish (Ictalurus punctatus), koi (Cyprinus rubrofuscus), and grass carp (Ctenopharyngodon idella) of at least 30 cm in length were individually anesthetized for 3 Tesla (3T) magnetic resonance imaging (MRI) of the brain. All fish achieved an adequate anesthetic level for prolonged immobilization during imaging. Diagnostic quality images were obtained for all subjects; however, the spatial resolution was maximized with larger fish. Imaging protocols were optimized for standard neuroimaging sequences. Additionally, inversion times for fluid-attenuation inversion recovery (FLAIR) sequences were adapted to the naturally high protein content of fish pericerebral fluid. Following imaging, the fish successfully recovered from anesthesia, were humanely euthanized, and were immediately processed to assess brain histopathology. Necropsy confirmed the sex and health status of each fish. A limited comparative MRI atlas was created of the brains of these species for clinical reference. Findings from the current study supported the use of 3T MRI as an adjunct diagnostic test for fish with suspected neurologic disease and provided a limited anatomic atlas of the teleost brain for use as a reference.

Use of computed tomography and magnetic resonance imaging to assess a case of spinal injury in a Showa koi Cyprinus carpio.

OBJECTIVE: A privately owned, 4-year-old female Showa koi (ornamental variant of Common Carp Cyprinus carpio) was presented for erratic swimming, air gasping, water spitting, and abnormal orientation in the water column. Initial physical examination revealed an obese patient with no external abnormalities except a small plaque localized to filaments on a right gill hemibranch. METHODS: The fish was anesthetized using AQUI-S 20E (10% eugenol solution) at 50 mg/L to facilitate diagnostic evaluation. Biopsy of the gill lesion yielded no significant findings. Whole-body computed tomography confirmed an excess of adipose tissue and mild scoliosis, with narrowing of the 10th-11th intervertebral space. A weight loss plan and need for repeat assessment were recommended. RESULT: The patient's original abnormal behaviors resolved over the following weeks, but it subsequently became hyporexic and depressed. Full-body magnetic resonance imaging (MRI) showed extensive alteration of vertebral centra, with multifocal compression of the spinal cord. Due to the patient's declining clinical condition and the grave prognosis based on MRI findings, the patient was humanely euthanized. CONCLUSION: Postmortem examination showed severe transmural myelomalacia associated with a vertebral subluxation. This case demonstrates the practical application of advanced cross-sectional imaging that has not been commonly afforded to fish or other lower vertebrates.

Intramuscular Grade 1 fibrosarcoma: Magnetic resonance imaging findings in 2 dogs.

Two adult neutered male dogs were presented for evaluation of firm, painless masses arising within muscle: an 8-year-old German wirehaired pointer dog with an accessory tricipital growth, and a 3-year-old German shepherd dog with a gracilis muscle growth. Magnetic resonance imaging (MRI) characteristics suggested malignant behavior, with a central fluid-like portion with a hyperenhancing lining, a nidus of disorganized tissue, and an extensive reactive zone, whereas histopathology was consistent with low-grade fibrosarcoma. This report describes histologically low-grade, yet biologically high-grade intramuscular fibrosarcoma, in which MRI provided detailed information on tumor behavior and assisted with biopsy and surgical planning.

Fibrosarcome intramusculaire de Grade 1 chez deux chiens : Imagerie par résonance magnétique. Ce rapport de cas décrit des fibrosarcomes intramusculaires de bas grade histologique mais au comportement biologique de haut grade ainsi que leur imagerie par résonance magnétique (IRM) chez deux chiens mâles castrés évalués pour des masses musculaires fermes et indolores : un Braque Allemand de 8 ans avec une masse originant de la branche accessoire du muscle triceps, et un Berger Allemand de 3 ans avec une masse au muscle gracile. L'IRM a révélé une zone centrale liquide bordée d'une mince couche au rehaussement marqué, adjacent à un foyer de tissu désorganisé, entourés par une zone réactive étendue. L'histopathologie des lésions révèle un fibrosarcome et malgré la présence d'anomalies histologiques de bas grade, l'infiltration des muscles adjacents est documentée par microscopie et les caractéristiques d'imagerie sont celles associées chez l'humain avec un comportement malin.(Traduit par les auteurs).

Diagnosis and treatment of epidural empyema in a pygmy goat.

A mixed-breed pygmy goat was presented for nonambulatory tetraparesis. Neurological examination was consistent with a C6 to T2 myelopathy. Initially, the goat was treated medically. Forty-three days later, magnetic resonance imaging (MRI) revealed an extradural mass compressing the cervical spinal cord. Magnetic resonance attributes of the mass were consistent with a slow-growing, fluid-poor lesion. The spinal cord was surgically decompressed. Epidural empyema secondary to Fusobacterium necrophorum was identified. Postoperative care consisted of anti-inflammatory medication, antimicrobials, and physical therapy. Ability to walk occurred by day 14 after surgery. Despite prolonged recumbency before surgery, the goat was clinically normal, and antimicrobials were discontinued on day 60 after surgery. Key clinical message: Epidural empyema can cause a compressive myelopathy which may result in varying degrees of paresis/paralysis. Clinical resolution and return of normal function occurred following the use of MRI to plan surgical decompression combined with extended use of antimicrobials.

Diagnostic et traitement d'un empyème épidural chez une chèvre pygmée. Une chèvre naine fut présentée pour tétraparésie non-ambulatoire, neuro-localisée au segment C6-T2. Un traitement conservateur fut initialement instauré. Quarante-trois jours plus tard, une IRM révéla une compression sévère de la moelle épinière cervicale par une masse extradurale faiblement liquide et à croissance lente. La moelle épinière fut chirurgicalement décompressée. Un empyème épidural secondaire à Fusobacterium necrophorum fut identifié. Des soins postopératoires à base d'anti-inflammatoires, d'antibiotiques ainsi qu'une rééducation physique furent instaurés. L'animal recouvra la capacité de marcher 14 jours plus tard. Malgré un décubitus prolongé, 60 jours après la chirurgie la chèvre était normale et les antimicrobiens furent interrompus.Message clinique clé :L'empyème épidural peut provoquer une myélopathie compressive pouvant entraîner divers degrés de parésie/ paralysie. La résolution clinique et le retour de la fonction normale sont survenus après l'utilisation de l'IRM pour planifier la décompression chirurgicale combinée à une utilisation prolongée d'antimicrobiens.(Traduit par Karin Gendron et Maëva Barozzi).

Imaging Ischemic and Hemorrhagic Disease of the Brain in Dogs.

Strokes, both ischemic and hemorrhagic, are the most common underlying cause of acute, non-progressive encephalopathy in dogs. In effect, substantial information detailing the underlying causes and predisposing factors, affected vessels, imaging features, and outcomes based on location and extent of injury is available. The features of canine strokes on both computed tomography (CT) and magnetic resonance imaging (MRI) have been described in numerous studies. This summary article serves as a compilation of these various descriptions. Drawing from the established and emerging stroke evaluation sequences used in the investigation of strokes in humans, this summary describes all theoretically available sequences. Particular detail is given to logistics of image acquisition, description of imaging findings, and each sequence's advantages and disadvantages. As the imaging features of both forms of strokes are highly representative of the underlying pathophysiologic stages in the hours to months following stroke onset, the descriptions of strokes at various stages are also discussed. It is unlikely that canine strokes can be diagnosed within the same rapid time frame as human strokes, and therefore the opportunity for thrombolytic intervention in ischemic strokes is unattainable. However, a thorough understanding of the appearance of strokes at various stages can aid the clinician when presented with a patient that has developed a stroke in the days or weeks prior to evaluation. Additionally, investigation into new imaging techniques may increase the sensitivity and specificity of stroke diagnosis, as well as provide new ways to monitor strokes over time.