Diplopia, Orbital Pain, and Vision Loss in a Middle-Aged Woman

A 59-year-old woman with type 2 diabetes had development of fluctuating, binocular, painless diplopia. She experienced headache, orbital pain, facial numbness, and progressive vision loss in the left eye. Her left eye vision worsened. Magnetic resonance imaging of the brain and orbit showed bilateral optic nerve enhancement. She started treatment with empiric intravenous corticosteroids for presumed optic neuritis, which resulted in transient improvement. Subsequently, her vision worsened to no light perception in the left eye, and she had fluctuating vision loss in the right eye. Cerebrospinal fluid evaluation was performed because the patient’s fluctuating diplopia and facial numbness suggested involvement of multiple cranial nerves. The cerebrospinal fluid showed white blood cells with lymphocytes, increased protein concentration, and negative oligoclonal bands and cytologic findings. Repeated brain magnetic resonance imaging 1 year after symptom onset showed persistent bilateral (left > right) optic nerve enhancement along with oculomotor nerve and left midbrain enhancement. We recommended left optic nerve biopsy to obtain the diagnosis and attempt to preserve vision in the threatened right eye. Because the patient had no light perception in the left eye for 5 months, with significant pallor of the optic nerve, it was unlikely that she had salvageable left eye vision. Furthermore, there was concern for lymphomatous infiltration of the optic nerve. Confirmation of a lymphoma diagnosis would be critical for initiation of specific chemotherapy. The pathologic analysis identified noncaseating granulomas. The finding of noncaseating granulomas was consistent with neurosarcoidosis infiltrating the left optic nerve. The patient was treated with intravenous methylprednisolone followed by prolonged, high-dose, oral corticosteroids along with corticosteroid prophylaxis of calcium, vitamin D, a proton-pump inhibitor, and dapsone for Pneumocystis prophylaxis Sarcoidosis is a systemic disease of unknown cause that can occur anywhere in the body but most commonly involves the lungs. The pathologic hallmark of sarcoidosis is noncaseating granulomas.