Surgical Treatment of a Chronic Brain Abscess and Growing Skull Fracture in a Dog

A 2-year-old female spayed Miniature Dachshund was presented for seizures and right prosencephalic signs. A multiloculated, ring-enhancing mass in the right cerebrum associated with dilation of the right lateral ventricle and brain herniation was seen on magnetic resonance imaging. An irregular calvarial defect with smoothly scalloped edges was seen overlying the mass on computed tomography. The mass was removed via craniectomy and was diagnosed as a chronic brain abscess caused by Peptostreptococcus anaerobius. The patient was maintained on antibiotics for 12 weeks. Follow-up MRI performed 14 weeks after surgery confirmed complete removal of the abscess as well as a contrast-enhancing collection of extra-axial material consistent with a chronic subdural hematoma. The neurologic abnormalities, including seizures, have improved in the 44 months since surgery. Brain abscesses in dogs can have an insidious clinical course prior to causing serious neurologic deterioration. Ventricular entrapment by an intracranial mass can contribute to acute neurologic decline. If surgically accessible, outcome following removal of a brain abscess can be excellent; aerobic and anaerobic bacterial culture should be performed in these cases. Subdural hematoma can occur following removal of a large intracranial mass. Growing skull fractures can occur in dogs but may not require specific surgical considerations.