Magnetic Resonance Imaging (Mri) Of The Central Nervous System In Large Felids

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Hecht S, Ramsay EC, Schumacher J, et al.

American College of Veterinary Radiologists 2012:111.

Introduction/Purpose: To date, reports describing CNS disorders in large felids and their diagnosis have been limited to a few papers detailing the use of radiographs, myelography and computed tomography (CT). MRI findings have been reported in lions with hypovitaminosis A and in a tiger cub following hypoxic arrest during general anesthesia. To our knowledge, MRI findings in a varied population of large felids with CNS disease have not been reported. The goal of this study was to describe MRI findings in large felids presented to UTVMC with brain or spinal disorders.

Methods: The MRI database was searched for large nondomestic cats in which MRI of the brain or spine was performed. The scans were reviewed. The medical records were evaluated and signalment, history, clinical signs and diagnosis/outcome were recorded.

Results: 14 MRI scans in 13 animals were available for review. All scans were performed using a 1.0T scanner (Siemens Magnetom Harmony). Patients included 5 tigers (Panthera tigris), 4 lions (Panthera leo) and 1 each of cheetah (Acinox jubatus), bobcat (Lynx rufus), caracal (Felis caracal), and leopard (Panthera pardus). Median age was 14 years (range, 6 months – 17 years). Areas imaged included the head/brain (n = 11), cervical spine (n = 1) and thoracolumbar spine (n = 2). Six cats are alive at the time of abstract submission, 6 animals had been euthanized. MRI sequences used for evaluation of the head/brain included T2-w, T1-w, fluid attenuated inversion recovery (FLAIR), T2*-w GRE and post contrast T1-w. MRI sequences used for evaluation of the spine included T2-w, T1-w, short tau inversion recovery (STIR), and half-Fourier- acquisition single-shot turbo spin-echo (HASTE). Diagnoses based on imaging findings were severe otitis media and cellulitis without intracranial extension (n = 1), Chiari-type malformation (presumed hypovitaminosis A) (n = 1), hydrocephalus and ependymal contrast enhancement due to intracranial blastomycosis (n = 1), normal brain MR examination (n = 7), and intervertebral disc herniation (n = 3).