Refractory seizures associated with an organic aciduria in a dog.

A 6-month-old, female Cavalier King Charles spaniel exhibited seizures that were difficult to control with standard anticonvulsants over a 12-month period. The diagnosis of an organic aciduria with excessive excretion of hexanoylglycine was determined when the dog was 20 months old. Recurrent and cluster seizures were eventually controlled with the addition of levetiracetam to potassium bromide and phenobarbital.

Comparison of conventional spin-echo and fast spin-echo magnetic resonance imaging in the canine brain.

T2-weighted fast spin echo and conventional spin echo are two magnetic resonance (MR) pulse sequences used to image the brain. Given the same scan parameters the resolution of fast spin-echo images will be inferior to that of conventional spin-echo images. However, fast spin-echo images can be acquired in a shorter time allowing scan parameters to be optimized for increased resolution without increasing the time to an unacceptable level. MR imaging of the brain of 54 dogs, suspected of having parenchymal brain abnormalities was performed using a 1.5 T scanner. Acquisition time ranged from 4 min 24 s to 7 min 16 s (average = 5 min 15 s) for fast spin-echo scans and from 6 min 32 s to 11 min 26s (average = 7 min 55s) for conventional spin-echo scans. All reviewers consistently rated the resolution of fast spin-echo images higher than the conventional spin-echo images (P = 0.000). The potential disadvantages of fast spin-echo acquisitions (motion artifacts, blurring, and increased hyperintensity of fat) did not affect the resolution of the images. Fast spin echo offers increased resolution in a comparable time to conventional spin echo by increased number of excitations and finer matrix size, thus improving the signal-to-noise ratio and spatial resolution, respectively.

Magnetic resonance imaging appearance of suspected ischemic myelopathy in dogs.

Ischemia and infarction of the spinal cord is a known cause of acute spinal injury in dogs. Currently, the diagnosis of spinal cord infarction in small animals is based on history, clinical signs, and the exclusion of other differentials with radiography and myelography. It is a diagnosis only confirmed through necropsy examination of the spinal cord. The aim of this paper is to describe the Magnetic resonance imaging (MRI) findings of the spinal cord of dogs with suspected spinal cord infarcts to utilize this technology for antemortem support of this diagnosis. This retrospective study evaluated the spinal MR examinations of 11 dogs with acute onset of asymmetric nonpainful myelopathies. All patients except one (imaged at 2 months) were imaged within 1 week of clinical signs and managed conservatively with minimal medical and no surgical intervention. They were followed clinically for a minimum of 4 months after discharge. MR findings in all dogs were characterized by focal, intramedullary, hyperintense lesions on T2-weighted images with variable contrast enhancement similar to what is reported in humans. Though it could not be used to diagnose spinal cord infarction definitively, MRI was useful in excluding extramedullary spinal lesions and supporting intramedullary infarction as a cause of the acute neurologic signs. Together with the history and clinical examination findings, MRI is supportive of a diagnosis of spinal cord infarction.

L-2-Hydroxyglutaric aciduria in Staffordshire Bull Terriers.

L-2-Hydroxyglutaric aciduria is an inborn error of metabolism, which has been recognized in humans since 1980. The metabolic defect responsible for the disease is unknown, but the disorder can be diagnosed in humans by elevations of the organic acid, L-2-hydroxyglutaric acid in the cerebrospinal fluid (CSF), plasma, and urine of affected patients. The disorder produces a variety of clinical neurological defects in humans including psychomotor retardation, seizures, and ataxia. There have previously been no recognized animal models of the disease. However, 6 Staffordshire Bull Terriers were recently identified with the disorder. The animals presented with a variety of clinical signs, most notably seizures, ataxia, dementia, and tremors. They were all screened for organic acid abnormalities in urine, and CSF and plasma (when available). Levels of L-2-hydroxyglutaric acid were elevated in all body fluids evaluated. The clinical, clinicopathologic, and magnetic resonance imaging (MRI) characteristics associated with L-2-hydroxyglutaric acid in Stafforshire Bull Terriers is reported herein and represents the first veterinary model of this inborn error of metabolism.

Tetraparesis in a cat with fibrocartilaginous emboli.

An 8-year-old cat, with a history of ataxia that progressed to tetraparesis over a 5-day period, was evaluated. A lesion was localized to the sixth cervical (C6) to second thoracic (T2) spinal cord segments based on physical and neurological examination findings. Blood work was unremarkable, as was survey radiography of the thoracic and abdominal cavities. Cerebrospinal fluid analysis showed moderate neutrophilic inflammation. A definitive diagnosis was not made until necropsy, at which time intravascular fibrocartilaginous embolization (FCE) of the cervical spinal cord was identified. This is only the third published report of FCE in the feline species and the first such case involving the cervical spinal cord.