Trabeculectomy May Prompt Structural ‘Reversal’ and Deep Retinal Perfusion Gains, Study Suggests

Researchers use advanced imaging to evaluate structural and vascular changes in the eye following trabeculectomy. These images from the study show a marked reduction in cup depth postoperatively. Photo: Cappellani F, et al. Vision. 2025; 9(4):97. Click image to enlarge. A new retrospective analysis offers fresh insight into how trabeculectomy impacts the optic nerve head (ONH) and alters retinal perfusion—changes that may inform postoperative monitoring in primary open-angle glaucoma (POAG). Using SD-OCT and OCT angiography (OCT-A), investigators evaluated structural and vascular outcomes two months after uncomplicated trabeculectomy and found evidence of both anatomic “reversal” of cupping and selective vascular improvement at the macula.The study included 22 POAG patients, with each participant’s fellow eye serving as an internal control. As expected, IOP dropped substantially after surgery, falling from a mean of 23.1mm Hg pre-op to 13.2mm Hg at two months. Beyond this pressure reduction, SD-OCT revealed notable morphologic remodeling of the optic nerve. Bruch’s membrane opening (BMO) contracted by about 5%, maximum cup depth (MCD) decreased by nearly one-third and cup area shrank by 44%.Despite these structural changes, neither peripapillary RNFL thickness nor ONH vascular density showed significant shifts postoperatively. Additionally, while the superficial capillary plexus (SCP) showed no appreciable postoperative change, the deep capillary plexus (DCP) demonstrated a significant boost in vessel density. Increases were noted in both the foveal and parafoveal regions.In their Vision paper, the study authors emphasize that trabeculectomy produced “significant structural remodeling of the optic nerve head,” marked by reductions in BMO, maximum cup depth and cup area following a reduction in IOP. They interpret these changes as evidence of the “mechanical reversibility of lamina cribrosa deformation once the stress of elevated IOP is relieved.” Furthermore, the research team noted that despite these anatomic shifts, RNFL thickness and superficial vascular parameters remained stable, while also adding that the increase in DCP vessel density likely represents a selective microvascular response to pressure reduction, potentially reflecting improved perfusion in deeper retinal layers.“Understanding the biomechanical and vascular mechanisms underlying these changes is critical for improving surgical outcomes, refining postoperative management strategies and advancing our knowledge of glaucoma pathophysiology,” the investigators concluded, while underscoring the need for additional longitudinal studies with larger cohorts and extended follow-up “to confirm these observations and explore their functional implications.”Click here for the journal source. Cappellani F, Castellino N, Zeppieri M, et al. Exploring Structural and Vascular Changes of the Optic Nerve Head After Trabeculectomy in Primary Open-Angle Glaucoma. Vision. 2025; 9(4):97. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.