Caecocentral Scotoma: A Rare Presentation of Optic Perineuritis

Abstract

Optic perineuritis (OPN) is a subtype of optic neuritis (ON) in which the inflammatory process involves meningeal sheath surrounding the optic nerve. Clinically, OPN simulates ON. However, in contrast to ON, patient with OPN shows sparing of central vision, improves dramatically with high-dose corticosteroid, are more likely to experience recurrence after stopping treatment. We report a rare case of caecocentral scotoma observed in a female with typical ON symptoms. Her magnetic resonance imaging showed features in line with OPN. She was treated with intravenous methylprednisolone 1 g/day for five days followed by slow tapering dose of oral prednisolone for one month. Her vision improved dramatically with a resolution of visual field defect. No relapses seen within two years of follow-up.

Keywords: caecocentral scotoma; doughnut sign; optic neuritis; optic perineuritis; retrobulbar optic neuritis; tram-track sign.

Figure 1. Humphrey visual field of the left eye shows: (A) a caecocentral defect (before treatment), and (B) improving central scotoma (after 3 days of treatment)

Figure 2. Post-contrast T1-weighted image with fat suppression shows: a) doughnut sign on coronal view (arrow) and b) tram-track sign on axial view (arrows)