Optic Disc Swelling After Intraocular Pressure Lowering Treatment in Acute Primary Angle Closure.

PURPOSE OF THE STUDY: The purpose of the study was to report cases with acute primary angle closure where optic disc swelling was documented after intraocular pressure (IOP) lowering by laser iridotomy.

PATIENTS AND METHODS: Two patients with acute primary angle closure underwent funduscopic examination of the optic disc and spectral-domain optical coherence tomography circumpapillary scanning at the time of acute primary angle closure attack before laser iridotomy, and after the laser iridotomy treatment.

RESULTS: Optic disc swelling was developed in both patients following IOP lowering by laser iridotomy, which was documented by spectral-domain optical coherence tomography imaging as a diffuse thickening of the circumpapillary retinal nerve fiber layer.

CONCLUSIONS: This is the first report demonstrating a temporal relationship between IOP lowering and optic disc swelling in patients with acute primary angle closure. Optic disc swelling documented after acute episode of acute primary angle closure may suggest choroidal effusion or axoplasmic overflow associated with sudden IOP lowering, rather than coexistence of other optic neuropathy.