Comparison of surgical outcomes between sulcus and anterior chamber implanted glaucoma drainage devices

PURPOSE: This retrospective case-control cross-sectional study compared the outcomes of sulcus placement of glaucoma drainage devices (GDD) versus traditional anterior chamber (AC) to test the hypothesis that sulcus placement results in fewer complications whilst maintaining similar efficacy. METHODS: This study included 45 patients in the sulcus group and 60 patients in the anterior chamber (AC) group who had undergone surgery from January 2014 to December 2017. Data were collected on pre-operative demographics, operative details and post-operative intraocular pressure and complications. The IOP, number of medications and complications between the two groups was compared. A P value of <5% was considered statistically significant. RESULTS: The sulcus group had significantly lower overall complications compared to the AC group with a comparable IOP decrease between groups. There were significantly lower rates of hyphaema in the sulcus (3 cases) compared to AC group (17 cases) (P < 0.05). Severe or late complications (implant exposure, corneal decompensation, endophthalmitis, poor vision, choroidal hemorrhage and cornea edema) were significantly lower in the sulcus group [2 eyes; 4.4%] compared to the AC group [13 eyes; 21.7%] (P < 0.05). The sulcus group required fewer medications during the follow-up period. CONCLUSION: Sulcus implantation of GDD resulted in less postoperative hyphaema and severe complications compared to AC implantation. Our findings concur with the literature that sulcus implantation is safe and effective for controlling IOP for various types of glaucoma. The long-term effects of endothelial cell loss for sulcus versus AC implantation require further evaluation.