PRIMARY OPTIC-NERVE MENINGIOMA AND PULMONARY METASTASIS IN A DOG

Primary optic nerve meningioma was diagnosed in a Labrador retriever based on history, clinical presentation, computed tomography, and histopathology. An orbitectomy was performed, but recurrence was evident 18 months postoperatively. Tumor invasion of the optic chiasm eventually caused an amaurosis of the fellow eye. Lymphoma was diagnosed two years postoperatively, and the dog died three weeks later Postmortem examination confirmed chiasmal invasion by the meningioma and revealed a solitary pulmonary metastasis. The lymph nodes, spleen, and liver were diffusely infiltrated by neoplastic lymphocytes.