Malignant optic glioma presenting as an acute anterior optic neuropathy.

Objective: To describe an uncommon case of malignant optic glioma and the challenges in its diagnosis.

Methods: Case report with funduscopic, magnetic resonance imaging (MRI), and automated field test correlations. Methods: A 60-year-old man presented with a 1-week history of left optic disk swelling and optic neuropathy that was initially diagnosed as nonarteritic anterior ischemic optic neuropathy (NA-AION).

Results: His clinical course deteriorated with progressive vision loss, acute orbital inflammation, and central retinal vein and artery occlusion, despite an improvement with a short course of steroids. MRI revealed enhancement of the left optic nerve, chiasm, and left optic tract. Initial optic nerve biopsy was negative and biopsy of optic tract confirmed a diagnosis of glioblastoma multiforme grade 4. The patient died 4 months after biopsy despite chemotherapy and radiotherapy.

Conclusions: The diagnoses of malignant optic glioma, anterior ischemic optic neuropathy, and optic neuritis have significant overlap of signs and symptoms. The authors report a case that demonstrates the difficulties in diagnosis, and propose additional presenting features of malignant optic glioma.