Assessment of the outflow drainage system in AMD after multiple anti-VEGF intravitreous injections

Abstract

Purpose : Sustained elevated IOP has been reported with all anti-VEGF agents used in ophthalmology and even among patients without prior history of glaucoma or ocular hypertension. Numerous potential mechanisms have been suggested to explain this phenomenon, many of them related to drainage system damage.
The key application of the WDT today is as a stress test that aims to identify sub-clinical abnormalities of the eye’s outflow facility as an indirect measure of the drainage system.
The aim of this study is to evaluate the outflow facility after multiple intravitreous injections of anti-VEGF agents and compare these results with their contralateral eye and eyes of normal, healthy controls who will not undergo the injection.

Methods : Twenty-six healthy control eyes and thirty-one patients with AMD that received at least 6 anti-VEGF intravitreous injections were selected. Only one eye from controls and AMD patients were included. If both eyes of AMD needed anti-VEGF injections, only one eye was randomly selected. Contra-lateral eyes of AMD patients wich not received any injections were included as a third group (fellow eye control).
The WDT was performed and Peak IOP was defined as the highest IOP measured during the WDT. IOP peaks and all IOP measurements were compared between eyes of control subjects, contralateral eyes of AMD patients, and AMD eyes.
Variables “baseline”, “time point” and “IOP peak” was analyzed with descriptive statistics: mean, standard deviation (SD), standard error (SE), median, minimum and maximum values, and 95% confidence interval (95% CI). Repeated measures analysis of variance (r-ANOVA) with time points (baseline, 15 min, 30 min and 45 min) were applied

Results : Baseline IOP measures were significantly higher in patients submited to multiple intravitreal injections, compared to controls and contralateral eyes.
The peak IOP and the difference between baseline and peak IOP were significantly higher in the intravitreal group.

Conclusions : Our results suggests that damage to outflow facility may play a role in the development of elevated IOP after multiple intravitreal injections of antiangiogenics.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.