Changes in choroidal thickness and axial length with intraocular pressure changes after trabeculectomy

Abstract

Background: Trabeculectomy is commonly performed in patients with chronic open angle glaucoma when medical therapy fails to control intraocular pressure (IOP). Objective: The aim of the current work was to evaluate choroidal thickness (C.T) changes with Enhanced Depth Imaging-Optical Coherence Tomography (EDI-OCT) & axial length (AXL) with ophthalmic A-Scan ultrasound after reduction of intraocular pressure (IOP) following trabeculectomy. Patients and Methods: The study was included 20 patients with open-angle glaucoma. The choroidal thickness was measured using enhanced depth imaging spectral domain optical coherence tomography (EDI-SD-OCT) and AXL of eye was measured using A-scan ultrasound before trabeculectomy and 1 month, 3 and 6 months postoperatively. Results: The changes of choroidal thickness before and after 1, 3 and 6 months of the operation found to have high statistically significant increase in SFCT-V, SFCT-V, NCT, TCT, SCT and ICT in 1st month postoperative with mean (217.65±27.03, 218±21.09, 216.9±28.86, 190.35±34.3, 223.1±24.82 and 244.8 ± 23.77) respectively, then they decreased in the 3rd month with mean (198.85 ±27.8, 197.8±23.3, 200.15±27.5, 178.35 ±31.9, 208.75±23.3 and 233.5±21.05) respectively, but it was not less than preoperative, and continued in decreasing in the 6th month with mean (187.3 ± 29.02, 186.95 ± 25.82, 188.95±27.47, 166.45±26.38, 197.7± 23.05 and 223.5±22.66) respectively, but it was not also less than preoperative. Conclusion: It could be concluded that intraocular pressure (IOP) reduction after trabeculectomy caused an increase in choroidal thickness (CT) this reduction of IOP was negatively correlated only with the increase in nasal, temporal, inferior and superior CT 3 mm away from the fovea.