Magnetic resonance imaging and brainstem auditory evoked responses in the diagnosis of cerebellar cortical degeneration in american staffordshire terriers

Abstract

The aim of the study was to determine the diagnostic usefulness of magnetic resonance imaging (MRI) and brainstem auditory evoked responses (BAER) in dogs suspected of having cerebellar cortical degeneration (CCD). In the years 2009–2011, six dogs with suspected CCD were examined. Both MRI and BAER examinations revealed abnormalities in all dogs (100%). By MRI, T2-weighted midsagittal images revealed an increased amount of cerebrospinal fluid (CSF) surrounding the cerebellum within the sulci of the folia in all dogs (100%). In 4 out of the 6 dogs (66.66%), cerebellar hypoplasia was more visible in the region of the dorsal cerebellar lobules. In 5 out of the 6 dogs (83.33%), the fourth ventricle was enlarged. In our studies, the brain to cerebellum ratio evaluated on the midsagittal image was 11.93%, in comparison to 14.9% in normal dogs. By BAER examination, the amplitude of the first and second waves was diminished and III–V interlatency was prolonged in 5 out of the 6 dogs (83.33%). In one out of the 6 dogs (16.67%), only the III–V interlatency was prolonged. In one dog (16.67%), somato-nervous deafness in the left ear was detected, whereas in the right ear the III–V interlatency was prolonged. MRI of the cerebellum is a reliable method for the antemortem diagnosis of CCD in American Staffordshire terriers, as is BAER examination. BAER is an objective diagnostic tool, which — along with other diagnostic modalities — can be helpful in the assessment, management and follow-up of dogs with cerebellar abiotrophy. It proved to be useful in determining the severity of neurological lesions in comparison to MRI findings, as well as in assessing the prognosis.