Comparison of Peripapillary and Submacular Choroidal Changes After Trabeculectomy and Phaco-Trabeculectomy in Open-Angle Glaucoma.

Purpose: Choroidal vascular and structural alterations are increasingly recognized as relevant to intraocular pressure (IOP) regulation and glaucoma pathophysiology. Surgical IOP reduction induces hemodynamic and biomechanical changes that may affect choroidal thickness and perfusion, particularly in the peripapillary and submacular regions. Although trabeculectomy is known to cause early postoperative choroidal expansion, the additional impact of concomitant phacoemulsification remains unclear. We compared early regional choroidal responses after trabeculectomy (Trab) alone and phaco-trabeculectomy (Phaco-Trab) in eyes with open-angle glaucoma (OAG). Patients and Methods: This retrospective study included patients with OAG who underwent Trab or combined Phaco-Trab after failure of maximal medical therapy. Preoperative and 1-month postoperative assessments included best-corrected visual acuity, Goldmann applanation tonometry, slit-lamp and fundus examinations, and enhanced depth imaging optical coherence tomography. Submacular and peripapillary choroidal parameters, including choroidal thickness (CT), luminal area (LA), stromal area (SA), total choroidal area (TCA), and choroidal vascularity index (CVI), were quantified using ImageJ software. Eyes with previous intraocular surgery, systemic vascular disease, media opacity, or postoperative complications were excluded. Intra- and intergroup comparisons were performed. Results: Fifty-five eyes were analyzed (30 Trab, 25 Phaco-Trab). Both groups showed significant postoperative IOP reduction (p<0.001). In the Trab group, submacular CT decreased significantly, whereas LA and TCA increased; CVI remained unchanged. In contrast, the Phaco-Trab group demonstrated significant increases in submacular CT, LA, TCA, and CVI at 1 month. In the peripapillary region, the Trab group showed increased temporal CVI, whereas the Phaco-Trab group demonstrated increased temporal LA. No significant correlation was found between IOP reduction and changes in choroidal parameters. Conclusion: Early postoperative choroidal responses differed between procedures. Phaco-Trab induced greater structural and vascular choroidal changes, likely due to the combined effects of IOP reduction and inflammation associated with cataract surgery. These findings highlight the choroid's dynamic role in postoperative recovery and warrant long-term investigation.