Maxillary osteolysis as a result of trigeminal nerve sheath tumour in a dog

Abstract

A 2.5‐year‐old, female, entire Labrador retriever presented with right‐sided head tilt, vestibular ataxia and right‐sided masticatory muscle atrophy. The most likely neuroanatomical localisation was the right‐sided brainstem involving the vestibular system and also the trigeminal nerve. Magnetic resonance imaging and computed tomography revealed enlargement of the right trigeminal nerve and osteolysis of the corresponding innervated maxillary bone. Histopathological analysis confirmed a malignant nerve sheath tumour of the trigeminal nerve that adhered, infiltrated, invaded and fragmented the bone. This is the first report and imaging description of maxillary osteolysis secondary to nerve sheath tumour in a dog.