Reasons for choice of glaucoma surgery in eyes not treated with anti-glaucoma medications

BACKGROUND: In the real world, some glaucoma patients can undergo an incisional glaucoma surgery without using medication. The rate of cases with no medication treatment at the time of surgery among those that underwent incisional glaucoma surgeries performed in our department was reported. METHODS: The department database of Shimane University Hospital for eyes that underwent incisional surgeries to manage glaucoma at the hospital between April 2018 and September 2020 were searched. By reviewing the medical charts of 1,417 consecutive eyes listed, 90 (6.4%) eyes of 67 subjects (mean age of 72 ± 16 years; 22 men, 29 eyes; 45 women, 61 eyes) who underwent a surgery without use of antiglaucoma medication were identified. The types of glaucoma, glaucoma procedures, and reasons for choosing the glaucoma surgeries rather than medical therapy were collected for the 90 eyes. RESULTS: Among the 90 eyes, primary angle-closure disease (PACD) (60%) was the most frequent type of glaucoma followed by EXG (17%), POAG (16%), and others (8%). Among the reasons for the choice of incisional surgery, relief of angle closure (64%) was the most frequent, the second most frequent was the incidental diagnosis of glaucoma during the ocular examinations both for that eye’s cataract surgery or the contralateral glaucoma surgery (13%). Other reasons included poor medication adherence (10%), dementia (6%), multiple medication allergy (3%), and acute IOP elevation other than PACD (3%). Cataract extraction (CE) alone (33%) was the most frequent glaucoma procedures performed in these eyes, followed by CE combined with goniosynechialysis (27%), CE + iStent (16%), CE + goniotomy by Tanito microhook ab interno trabeculotomy or using the Kahook Dual Blade (11%), Ahmed Glaucoma valve implantation (11%), and trabeculectomy (2%). CONCLUSION: In the real-world, 6.4% of incisional glaucoma surgeries were performed in the absence of medication use; of them, 32 eyes (2.3%) were with open angle glaucoma. In open angle glaucoma, the reasons can be classified into; 1) patients’ inability to instill the medication, 2) incidental diagnosis of glaucoma during the pre-surgical examinations, and 3) the eyes with acute IOP rise.