Efficacy and Safety of iStent Inject Implantation in Manual and Femtosecond Laser-assisted Cataract Surgery before Lens Extraction

AIM: To describe the efficacy and safety of iStent implantation prior to phacoemulsification in manual as well as femtosecond laser-assisted cataract surgery (FLACS), and highlight this approach as a reasonable, if not necessary, step to advance one's ability and confidence in the use of microinvasive glaucoma surgery (MIGS) technology in phakic patients. METHODS: A retrospective consecutive case series of patients with open angle glaucoma or ocular hypertension who underwent iStent inject implantation followed by cataract surgery (manual or FLACS). All cases underwent postoperative video review and were assessed and classified for intraoperative lens injury and hyphaema. Postoperative data included intraocular pressure (IOP), medication usage and adverse events. RESULTS: Sixty-three eyes (n = 40 manual, n = 23 FLACS) were analyzed. Preoperatively, the mean IOP was 19.2 ± 4.9 mm Hg on 1.4 ± 0.96 mean medications, with 100% of eyes treated with medication. Intraoperatively, no lens injury was identified, and no significant hyphaema that impeded surgery occurred. At 6 months postoperative, mean IOP was 14.2 ± 1.8 mm Hg (38% reduction: p < 0.001), and >90% of eyes had IOP ≤ 16 mm Hg. The mean number of medications reduced to 0.11 ± 0.3 (92% reduction: p < 0.001), with 89% of eyes medication free. Safety was excellent for both manual and FLACS, with two iStents implanted in all eyes, and no cases of significant hyphaema or lens injury. CONCLUSION: Early implantation is safe, maximizes corneal clarity and angle visualization, avoids the risk of non-implantation due to surgical complications, and has a high success rate in both manual cataract surgery and the setting of FLACS. CLINICAL SIGNIFICANCE: The conventional recommended approach of iStent implantation following cataract extraction has been adopted by many, however, with the advent of stand-alone procedures and concern about potential lens injury, there is an opportunity to gain experience with minimal risk in patients undergoing MIGS procedures combined with cataract surgery by implanting iStents at the start of the procedure. There is currently little emphasis or data published in the literature on an early approach to implantation to guide surgeons. HOW TO CITE THIS ARTICLE: Manning DK, Haider A, Clement C, et al. Efficacy and Safety of iStent Inject Implantation in Manual and Femtosecond Laser-assisted Cataract Surgery before Lens Extraction. J Curr Glaucoma Pract 2022;16(2):105-110.