Optic Nerve Head, Retinal Nerve Fiber Layer and Ganglion Cell Complex Changes after Successful Subscleral Trabeculectomy

Abstract

Background: The utilization of optical coherence tomography [OCT] has demonstrated its efficacy in the identification and assessment of glaucomatous impairment.The Aim of the work: The objective of this study is to evaluate and compare the alterations in Optical Coherence Tomography measurements, specifically the Optic Nerve Head, Retinal Nerve Fiber Layer Thickness, and Ganglion Cell Complex, in patients diagnosed with primary open-angle glaucoma before and after undergoing subscleral trabeculectomy surgery.Patients and Methods: This study included 25 eyes having primary open angle glaucoma scheduled for subscleral trabeculectomy at Al-Azhar university hospital, Damietta. Ethical approval was obtained from ethics committee of Al-Azhar university, faculty of medicine. A written informed consent was obtained from all patients included in the study after nature and possible consequences of the procedure has been explained. The patients were evaluated by Topcon 3D OCT 2000 device. Standard resolution scans captured the temporal and nasal quadrants [nasal-temporal 0° -180°] before subscleral trabeculectomy operation and was evaluated at 1 week, 1 month and 3 months post operativelyResults: According to the total RNFL, it was 60.7 ± 13.9 µm preoperatively, and significantly increased to 71.9 ± 14.3 µm at 1 month postoperative and also, increased to 74.7 ± 13.6 µm at 3 months postoperative [P value = 0.001 for both]. According to the total GCC, it was 65.5 ± 14.9 µm preoperatively, and significantly increased to 74.1 ± 13.9 µm at 1 month postoperative and also, increased to 76.2 ± 13.5 µm at 3 months postoperative [P value = 0.001 for both]. In terms of IOP, it was significantly decreased from 35.5 ± 5.5 mmHg to 13.7 ± 1.4 at 1 month postoperative [P value = 0.001], and also, decreased to 13.9 ± 1 mmHg at 3 months postoperative [P value = 0.001].Conclusion: Sub scleral trabeculectomy is an effective surgical procedure for the treatment of Open angle glaucoma.

Keywords

• optic nerve head
• retinal nerve fiber layer
• ganglion cell complex