Abstract
Retinal pigment epithelium (RPE) tears are frequently observed following anti-vascular endothelial growth factor therapy for age-related macular degeneration. While rare, giant RPE tears have also been reported secondary to choroidal detachment (CD) induced by postoperative hypotony after trabeculectomy (TLE). Although mechanical stress on the RPE is considered a common underlying factor in both scenarios, the exact mechanisms remain unclear. This report describes a case of a giant RPE tear originating from the site of a previously untreated choroidal neovascularization (CNV) following TLE. A 65-year-old male underwent TLE for intraocular pressure (IOP) control in his left eye with primary open-angle glaucoma. Preoperative IOP was 39 mmHg, and fundus examination revealed untreated CNV and sub-RPE hemorrhage. The scleral flap sutures were sequentially laser lysed on postoperative days two and four, as the postoperative IOP remained stable between 12 and 14 mmHg. On postoperative day seven, IOP decreased to 4 mmHg, and CD was observed. Following observation, the IOP increased to 7 mmHg on postoperative day 10, revealing a giant RPE tear and serous retinal detachment (SRD). An additional scleral flap suture was performed on the same day, and the IOP subsequently stabilized around 10 mmHg. During follow-up, the SRD spontaneously resolved by postoperative day 41, while the RPE tear persisted. Visual field testing revealed worsening of visual field defects compared to preoperative findings, with defects corresponding to the location of the RPE tear. The rapid IOP reduction following TLE may have induced mechanical stress on a vulnerable RPE region affected by CNV, leading to the RPE tear. A rapid IOP reduction may increase the risk of an RPE tear when vulnerable RPE areas exist due to CNV or other factors; therefore, careful preoperative evaluation for vulnerable RPE regions and cautious perioperative IOP management should be considered.