A comparative study of knotless versus knotted transscleral suture-fixated intraocular lens implantation

PURPOSE: To compare functional outcomes and complication rates of two scleral fixated intraocular lens implantation (SFIOL) techniques. METHODS: In this retrospective study, there were 30 eyes of 30 patients who underwent SFIOL implantation for dislocation of the IOL or crystalline lens. Group 1 (n = 17) comprised patients who received scleral-fixated polymethylmethacrylate (PMMA) IOL implantation through a self-sealing sclerocorneal tunnel with the suture burial technique, and group 2 (n = 13) comprised patients who received scleral-fixated foldable acrylic IOL implantation with a cartridge using a self-sealing clear corneal incision (CCI) with knotless Z-suture technique between 2014 and 2019. Surgical outcomes concerning safety, efficiency, visual function, induced astigmatism with vector analysis, and complications were compared. RESULTS: The indications were dislocated crystalline lens (n = 5/30), dislocated IOL (n = 17/30), and dropped nucleus (n = 8/30). The mean follow-up time was 50.65 ± 14.02 months in group 1 and 15.69 ± 3.71 months in group 2 (P < 0.001). The postoperative visual acuity improvement was statistically significant in both groups (P < 0.001). Surgically induced astigmatism was significantly higher in group 1 (2.68 ± 1.04 D) compared with group 2 (1.6 ± 1.0 D) at month 12 (P = 0.001). Postoperative complications included suture exposure (n = 1 in group 1) and cystoid macular edema (n = 1 in group 1; n = 1 in group 2). CONCLUSION: Both SFIOL techniques are safe and effective in the absence of adequate capsular support. However, the knotless Z-suture technique appears to be superior to the suture burial technique with regard to suture exposure-related complications. In addition, self-sealing CCI appears to be superior to self-sealing sclerocorneal tunnel with regard to surgically induced astigmatism.