Impact of postoperative choroidal detachment on trabeculectomy outcomes: a four-year comparative study

BACKGROUND: The aim of this study was to compare trabeculectomy outcomes in patients with and without post-operative serous choroidal detachment (CD) and establish an association between CD and trabeculectomy outcomes. METHODS: In this 4-year retrospective cohort study, medical records of glaucoma patients older than 18 who underwent primary trabeculectomy with Mitomycin-C between 2012 and 2020 were reviewed. Phakic eyes without history of any other intraocular surgery and with at least one year of follow-up were included in the study. Postoperative CD was defined as clinically visible CD developed within the first postoperative week. Cases were categorized into with and without CD and trabeculectomy outcomes were compared. Comparison was carried out using postoperative intraocular pressure (IOP), glaucoma medications and surgery success. Two levels of success were defined regardless of glaucoma medications; criteria A) 5 < IOP < 19 mmHg and criteria B) 5 < IOP < 16 mmHg. In addition to the defined IOP ranges, IOP reduction less than 20% from baseline and further glaucoma surgery were also counted as surgery failures. RESULTS: Total of 183 patients including 153 without CD (mean age 58.73 ± 11.40 years, mean IOP 23.7 ± 6.63 mmHg) and 30 with CD (59.00 ± 12.59 years, mean IOP 22.2 ± 3.83 mmHg) entered the study. Post-trabeculectomy mean IOPs were significantly higher in the CD group at all follow-up visits at year 1 through 4 (14.70, and 14.82 mmHg vs. 11.03, and 12.59 mmHg; p-value < 0.05). Similarly mean number of glaucoma medications was higher in the CD group at all follow-up visits (p-value > 0.001). Based on success criteria A, cumulative probability of success for patients with CD wasn’t significantly different compared to those without CD at years 1 through 4 (80.0%, and 69.6% vs. 88.2%, and 74.1% respectively; p-value > 0.05, log-rank). However, based on success criteria B, patients with CD had significantly lower cumulative probability of success at years 1 through 4 (50.0% and 8.9% vs. 79.7% and 59.8%, p-value < 0.001). CONCLUSION: We established that early post-trabeculectomy serous choroidal detachment is associated with adverse surgery outcomes. Lower rate of surgery success and higher mean postoperative IOP and glaucoma medications were observed in patients with post-trabeculectomy choroidal detachment and this was more pronounced in patients who required more stringent IOP control (success definition 5 < IOP < 16 mmHg).