Cerebral healing after craniotomy to evacuate a Coenurus cerebralis cyst

An 11-month-old ewe developed neurological signs caused by a space-occupying lesion in the left cerebral hemisphere. Successful surgical evacuation of a Coenurus cerebralis cyst was carried out, the neurological signs regressed and the ewe produced twins in the following breeding season. Sixteen months after the surgical treatment the ewe was found dead and necropsy revealed a vegetative endocarditis. In the brain, at the site of cyst evacuation, there was a collapsed subcortical cavity lined by siderotic fibrovascular tissue and surrounded by a modest glial reaction. These observations confirm that the clinical signs of cerebral coenuriasis are related to the space-occupying effect of the parasitic cyst and indicate that partial replacement by gliomesodermal tissue plays a part in healing of the collapsed cyst.