Swelling of atrophic optic discs in idiopathic intracranial hypertension

Authors: Jim Shen Chu Xie¹, Laura Donaldson¹, Edward Margolin². ¹McMaster University, ²University of Toronto.

Author Disclosures: Jim Xie: None Laura Donaldson: None Edward Margolin: None


Abstract Body: 

Purpose: Monitoring patients with idiopathic intracranial hypertension (IIH) who have optic atrophy may be difficult as papilledema may not be appreciable on ophthalmoscopy. This study is the first to evaluate whether recurrence of papilledema can be detected in this population using peripapillary optical coherence tomography (OCT). 

Study Design: Retrospective chart review. 

Methods: Serial clinical assessments, ophthalmoscopy, and peripapillary OCT were reviewed in a cohort of patients with IIH and optic atrophy. Atrophy was defined as moderate if average peripapillary retinal nerve fibre layer (pRNFL) thickness was <=80 μm and severe if average pRNFL thickness was <=60 μm on at least two consecutive high quality OCT scans. Based on the upper tolerance limit associated with the 95 th percentile of test‐retest variability, mean pRNFL elevation >=6 μm with subsequent decrease to baseline thickness was considered papilledema. 

Results: In a cohort of 165 patients with IIH, 32 eyes of 20 patients and 22 eyes of 12 patients demonstrated moderate and severe optic atrophy, respectively. Over a median follow‐up of 198.5 weeks (range 14.0, 428.9), half of all patients (15/30) had an episode of mean pRNFL thickening and 40% (12/30) had a bilateral episode. The median percent pRNFL increase was 13.7% (range 7.5, 111.8) and 7 eyes (13.0%) of 5 patients (16.7%) showed pRNFL thickening greater than 20.0% from baseline. pRNFL elevation was associated with at least one relapse‐suggestive feature (i.e. potential trigger, symptom worsening, observable optic disc edema, visual field deterioration) in 75.9% of episodes (22/29). The rate and magnitude of pRNFL swelling were similar between moderately versus severely atrophic eyes. 

Conclusions: Papilledema recurrence can be detected in atrophic optic discs using OCT. All patients with atrophic IIH should be longitudinally monitored with pRNFL measurement. Concurrence of other relapse‐suggestive features should prompt further evaluation and consideration of treatment escalation.

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