Characteristics and Treatment Outcomes of Hypotony Maculopathy Postglaucoma Filtering Surgery: An Optical Coherence Tomography-Based Study

Abstract

Précis: Bleb revision procedures for hypotony maculopathy (HM) following glaucoma filtering surgery show promising outcomes, including notable improvements in visual acuity and IOP. Purpose: This study assesses morphologic characteristics using SD-OCT in patients with HM following glaucoma filtering surgery and evaluates the results of its treatment. Materials and Methods: A retrospective analysis of all HM patients between January 2019 and March 2023. Inclusion criteria consisted of both preoperative and postrevision SD-OCT images of the macula and the presence of HM as observed on OCT images preoperatively. HM was graded according to its appearance in OCT both prerevision and postrevision surgery. Changes in visual acuity and IOP were assessed. Results: A total of 45 eyes of 45 patients were included. In all, 21 eyes had HM limited to retinal pigment epithelium (RPE), 18 eyes had involvement of RPE and photoreceptor layers, and 6 eyes had additional intraretinal or subretinal edema. After revision surgery with IOP elevation, 64% of eyes had complete HM regression with no HM signs in OCT imaging. Overall, 80% of patients achieved at least 1 grade improvement in HM. Preoperative visual acuity increased from 0.7±0.4 (logMAR) to 0.4±0.4 at 2 weeks postoperatively, over the course of an increase of IOP from 3.5±1.8 to 17.1±10.6 mm Hg at day 1. Eyes with complete HM regression had higher IOP at day 1 compared with those without improvement (P=0.04). The median time between HM onset and revision was 10.0 days for those with complete regression and 27 days for those without improvement (P=0.04). Conclusions: Bleb revision procedures for HM following glaucoma filtering surgery show promising outcomes, including notable improvements in visual acuity and IOP. The timing of revision surgery appears to influence the outcome. In our study, earlier intervention was associated with better results. Even delayed surgeries can lead to an improvement, although complete morphologic restoration may not be achieved in advanced grades of HM.