# Severe Permanent Visual Decline After Hypotony-Induced Retinal Pigment Epithelial Changes

## TL;DR

A rare case shows how short-term low eye pressure after surgery can lead to permanent vision loss due to retinal damage.

## Contribution

This case report highlights a rare but severe complication of glaucoma surgery involving irreversible retinal pigment epithelium changes.

## Key findings

- Short-term hypotony after glaucoma surgery can cause permanent subfoveal RPE changes.
- Choroidal detachment and hypotony maculopathy may lead to irreversible visual loss.
- Fundus autofluorescence is effective in detecting subtle RPE changes.

## Abstract

Postoperative hypotony accompanied by choroidal effusions and maculopathy are well-recognized complications following glaucoma shunt surgery. We report a rare case of an elderly patient with irreversible visual loss in his left eye (OS) caused by retinal pigment epithelium (RPE) changes secondary to short-term hypotony maculopathy and choroidal detachment after a Paul glaucoma drainage device implantation.

An 83-year-old man presented with recurrent episodes of transient loss of vision in his OS. Examination of his OS revealed high intraocular pressure (IOP), a one-piece in-the-bag posterior chamber intraocular lens (IOL) with pseudophacodonesis and hyphema, pointing toward the diagnosis of uveitis-glaucoma-hyphema (UGH) syndrome. Despite the urgent extraction of the IOL-capsular bag complex, pars plana vitrectomy, and implantation of a retro-pupillary iris-claw lens, the IOP was poorly controlled with maximal medical treatment, necessitating the implantation of a Paul drainage device. Postoperatively, kissing choroidal detachments were observed due to early postoperative hypotony. Although the IOP soon normalized and the choroidal detachment resolved, the visual acuity remained markedly reduced due to apparently permanent hypotony-related subfoveal RPE changes that were well documented with fundus autofluorescence.

This case highlights that even a short period of hypotony compounded by choroidal detachment and hypotony maculopathy can cause permanent RPE damage and eventually irreversible visual loss. The pattern and distribution of the RPE changes were associated with the areas of prior choroidal detachment. Notably, autofluorescence proved particularly useful for the assessment of these subtle but vision-threatening RPE changes.