Induced Corneal Astigmatism after Trabeculectomy

Background: Presently, glaucoma surgery aims to reduce intraocular pressure (IOP) since elevated IOP is a significant risk factor for the development of glaucoma and because reducing IOP can retard the disease's progression. Aim: To evaluate induced astigmatism after trabeculectomy. Subjects and methods: The 60 eyes of 36 patients with uncontrolled OAG were enrolled in this prospective interventional trial using a systematic random sampling technique. The patients were recruited from the outpatient ophthalmology clinics of Al-Azhar University Hospitals between January 2024 and September 2024. Results: Regarding surgical-induced astigmatism, the level was significantly lower in patients without MMC [2.52±0.79] than in patients with MMC [3.03±0.82], with a p-value of 0.025 after 1 month. Also, in each group, the level of surgical-induced astigmatism was significantly increased after 6 months compared to preoperative levels, with a p-value<0.001 for patients with MMC and 0.003 in patients without MMC. Moreover, after 1 month, there was a negative connection between the decrease in intraocular pressure and the increase in astigmatism (r=-0.311, p-value=0.016). Conclusion: Subscleral Trabeculectomy is an effective procedure in controlling IOP in POAG. Postoperative induced astigmatism is a common finding after Subscleral Trabeculectomy and is secondary to conjunctival stitches. No significant relation between postoperative astigmatism and the use of mitomycin. Removal of scleral stitches effectively decreases postoperative astigmatism. A rapid decrease in IOP increases postoperative astigmatism.