One-year Outcomes of Trabecular Micro-bypass Stent Implantation Combined with Cataract Surgery in Korean Glaucoma Patients Under Different Levels of Glaucoma Severity

초록

Purpose : To evaluate the 1-year outcomes of trabecular micro-bypass stent implantation combined with cataract surgery under different levels of glaucoma severity. Methods : This is a retrospective observational study of glaucomatous Korean eyes which have undergone iStent implantation combined with phacoemulsification with 1-year follow-up. The eyes were divided in to three groups (mild=G1, moderate=G2, and advanced=G3) according to glaucoma severity. Intraocular pressure (IOP), number of glaucoma medications, complications, and additional glaucoma surgeries were assessed preoperatively and at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year postoperatively. Preoperative IOP, glaucoma medications, biometric parameters and variables for glaucoma severity were evaluated as potential predictors of postoperative IOP change. Results : Fifty-eight eyes of open angle glaucoma were included. The mean IOP decreased significantly from 15.6±3.0 mmHg preoperatively to 13.8±2.2 mmHg at 1 year after surgery (p<0.001). The mean number of glaucoma medications also decreased significantly from 2.10 ± 0.78 to 1.79 ± 0.93 at 1 year postoperatively (p=0.008). Three cases (5.2%) required additional glaucoma surgery. In G1, the mean IOP decreased from 14.8±1.7 mmHg preoperatively to 13.5±1.9 mmHg at 1 year postoperatively (p = 0.003) and the mean number of medications decreased from 1.65±0.68 to 1.31±0.47 at 1 year postoperatively (p = 0.001). In G2, the mean IOP decreased from 15.3±3.9 mmHg preoperatively to 13.4±2.4 mmHg at 6 months postoperatively (p=0.015) and did not decrease at 1 year postoperatively (14.1±2.4 mmHg, p>0.05). However, the mean number of medications decreased from 2.53±0.68 to 1.80±0.67 at 1 year postoperatively (p= 0.003). In G3, the mean IOP decreased from 17.1±3.2 to 14.0±2.6 mmHg at 1 year postoperatively (p=0.002) and the mean number of medications decreased from 2.5±0.6 to 1.8±0.6 at 6 months postoperatively (p=0.007) and did differ significantly at 1 year postoperatively (p>0.05). Only preoperative IOP was found to be associated with IOP reduction at postoperative year one (p<0.001). Conclusions : These findings suggest that iStent implantation combined with cataract surgery can be an effective treatment option in Korean glaucoma patients to lower IOP or reduce medication burden across different levels of glaucoma severity.