■ Researchers led by Paul R. Healey, PhD, of the University of Sydney in Australia set out to systematically identify and quantitatively evaluate the efficacy of iStent devices (iStent and iStent inject; Glaukos) when performed independently of cataract surgery in patients with open-angle glaucoma. A systematic review of the literature was undertaken to identify studies of standalone trabecular microbypass glaucoma surgery with iStent devices in patients with open-angle glaucoma. All randomized trials were considered, as well as nonrandomized studies that included at least 6 months of follow-up or more than 10 eyes.

A total of 13 studies were identified providing data for 778 eyes implanted with iStent devices. A weighted mean IOP reduction of 31.1% was observed at 6-12 months. In studies reporting longer-term outcomes (36-48 months or 60 months), the weighted mean IOP reduction was 30.4% and 32.9%, respectively. Medication burden was reduced by approximately 1.0 medications at 6-18 months and 1.2 medications at 36-60 months. Adverse events reported in more than 5% of participants were progression of pre-existing cataract/cataract surgery and loss of BCVA, but these rates were no different from those reported in comparator medical therapy study arms. The researchers, who reported their findings in the Journal of Glaucoma, concluded that the results from these studies support the independent effect of the iStent trabecular bypass devices on IOP and medication burden over a duration of follow-up of up to 5 years. GP