Authors: Prem Nichani, Jonathan Micieli

Author Disclosure Block: P. Nichani: None. J. Micieli: None.

Abstract Body:

Purpose: The well-known ophthalmological manifestations of idiopathic intracranial hypertension (IIH) are papilledema and abducens nerve palsy, but less commonly recognized retinal manifestations may occur. The goal of this study was to identify significant IIH retinal changes that may occur in a group of patients with high-quality retinal photographs and optical coherence tomography (OCT) of the macula. A detailed literature review was also undertaken to provide comprehensive data on this topic.

Study Design: Retrospective case series and literature review.

Methods: Consecutive IIH patients presenting from July 2018 to October 2019 to a tertiary neuro-ophthalmology practice at Kensington Vision and Research Centre (KVRC) at the University of Toronto were included in the study. High-quality fundus photographs were routinely obtained for all patients referred for IIH at this centre. Patients were included if they met the modified Dandy Criteria for diagnosis and clinical characteristics were retrieved for each patient. A comprehensive literature review was conducted using Ovid MEDLINE and EMBASE using keywords and medical subject headings.

Results: Ninety-six patients were included in the study and four patients (two women, two men) had significant retinal findings: bilateral venous stasis retinopathy secondary to severe papilledema, choroidal neovascularization from adjacent papilledema, bilateral macular exudate, and bilateral subfoveal fluid. At presentation, amongst the four patients, average age was 35.8 ± 11.5 years (range: 23-49), body mass index was 46.1 ± 6.2 kg/m², visual acuity ranged from 20/20 to 20/500 in either eye, and the average mean deviation on Humphrey visual field testing was -11.6 ± 11.5 dB. The patient with venous stasis retinopathy secondary to severe papilledema was treated with VP-shunting whereas all others were treated with weight loss and acetazolamide. The patient with significant macular exudate had elevated blood pressure which was also treated. Retinal manifestations of IIH reported in the literature include choroidal infarction (n=1), choroidal neovascular membranes (n=31), macular exudate from associated papilledema (n=3), venous stasis retinopathy (n=8), subfoveal fluid from adjacent papilledema (n=20). Retinal and choroidal folds were studied prospectively in the IIH treatment trial and found in 19% and 1% of patients, respectively.

Conclusions: Significant retinal manifestations associated with IIH include venous stasis retinopathy, choroidal neovascularization, macular exudate and subretinal fluid. These changes may result in a reduction in visual acuity or a visual field defect distinct from that caused by papilledema.