Low-field magnetic resonance imaging of a pyocephalus and a suspected brain abscess in a German Shepherd dog

Magnetic resonance imaging was performed on an eight-year-old, neutered fem ale German Shepherd dog with a history of acute depression, inappetence, an d hyperthermia. A lesion in the cerebrum was suspected. Possible differenti al diagnoses were meningoencephalitis, neoplasia, and vascular lesion (infa rction, bleeding). A ring enhancing lesion was found in the basal ganglia o n the left side with edema of the surrounding brain tissue. A similar mass lesion was present in the right pterygoid musculature. With inversion recov ery sequences an altered composition of the cerebrospinal fluid (CSF) in th e left lateral ventricle could be detected. CSF analysis confirmed a pyocep halus, probably due to rupture of a brain abscess into the left lateral ven tricle.