Multicentric Glioblastoma Multiforme Mimicking Optic Neuritis

Abstract

A 49-year-old previously healthy woman presented with acute painless visual loss in the right eye, a right relative afferent pupillary defect, and a normal fundus examination. She was diagnosed with retrobulbar "optic neuritis" and given a course of intravenous steroids. Despite treatment, however, she continued to lose vision and serial visual field testing confirmed a junctional scotoma in the fellow eye. Cranial magnetic resonance imaging (MRI) showed a mass at the junction between the right optic nerve and the anterior aspect of the chiasm and a right frontal lesion that proved to be multicentric glioblastoma multiforme. Clinicians should be aware of the possibility of aggressive neoplasm in the differential diagnosis of retrobulbar optic neuritis.

Keywords: Glioblastoma multiforme; malignant optic nerve glioma of the adult; optic nerve tumour; optic neuritis.

Figure 1.

Automated visual field at presentation demonstrating diffuse depression OD and a mild superotemporal depression OS consistent with the junctional scotoma.

Figure 2.

Repeat automated visual field confirms the junctional scotoma OS suggestive of posterior right optic nerve/anterior chiasm involvement.

Figure 3.

Brain MRI. (A) Axial T2-weighted image shows a heterogeneous multilobulated hyperintense mass in the right frontal lobe with adjacent vasogenic oedema and mild displacement of the midline due to mass effect. (B) Coronal and (C) axial T1-weighted images of a second mass (arrows) located at the anterior aspect of the chiasm, on the right, with ring enhancement due to neoplastic infiltration.