Comparing iStent versus CyPass with or without phacoemulsification in patients with glaucoma: a meta-analysis

[Micro-invasive glaucoma surgery]

Glaucoma is a severe, rapidly progressing disease that in the absence of proper treatment leads to blindness in 20% of patients. According to the World Glaucoma Association, this disease is the most socially significant in modern ophthalmology and requires searching for new and effective methods of treatment. This article presents the results of research and reviews on this issue, considers both conservative therapy and surgical methods of treatment, analyzes in detail modern methods of micro-invasive eye surgery actively used in clinical practice. The article also describes indications for a various types of interventions, as well as the effect achieved by them and the possible complications, and presents the conclusions about the possibility of using these procedures in wide clinical practice.

Surgical and Perioperative Considerations for the Treatment of Cataract in Eyes with Glaucoma: A Literature Review

Cataract surgery in the presence of glaucoma poses certain challenges that need to be addressed to offer the maximum benefit without complications. In this paper, we are reviewing the preoperative assessment, surgical options, the planning, and postoperative care. Cataract surgery can help reduce the intraocular pressure alone or combined with MIGS. When performed in patients with glaucoma, it can transiently increase the intraocular pressure and later on decrease the IOP to levels lower than the postoperative. The preoperative IOP and biometric characteristics are the main predictors of the postoperative course of IOP. The combination of cataract surgery with trabeculectomy remains controversial, in terms of best timing of each operation.

Standalone iStent Trabecular Micro-bypass Glaucoma Surgery: A Systematic Review and Meta-Analysis

PRECIS

Standalone trabecular micro-bypass glaucoma surgery with the iStent devices is associated with clinically relevant reductions in intraocular pressure (IOP) sustained over a reasonably long-term while simultaneously reducing medication burden and a relatively favorable safety profile.

PURPOSE

While there is a relatively large body of evidence supporting the implantation of the iStent trabecular micro-bypass devices during phacoemulsification in patients with open-angle glaucoma (OAG), its efficacy as a standalone procedure has been less widely reported. The aims of this study were to systematically identify and quantitatively evaluate the efficacy of iStent devices (iStent and iStent inject) when performed independently of cataract surgery in patients with OAG.

METHODS

A systematic review of the literature was undertaken in August 2019 to identify studies of standalone trabecular micro-bypass glaucoma surgery with iStent devices in patients with OAG. All randomized trials were considered and nonrandomized studies that included at least 6 months of follow-up or more than 10 eyes. Key efficacy analyses included postoperative IOP and medication use, which were used to evaluate weighted mean differences from baseline, and the proportion of eyes free of ocular medication. Postoperative adverse events were descriptively summarized.

RESULTS

A total of 13 studies were identified including 4 randomized controlled trials and 9 nonrandomized or single-arm studies providing data for 778 eyes. In eyes implanted with iStent devices, a weighted mean IOP reduction of 31.1% was observed at 6 to 12 months. In studies reporting longer-term outcomes (36 to 48 mo or 60 mo), the weighted mean IOP reduction was 30.4% and 32.9%, respectively. The pooled weighted mean reduction in IOP from baseline across all studies at 6 to 12 months and 36 to 60 months poststent implantation was 7.01 mm Hg (95% confidence interval: 5.91, 8.11) and 6.59 mm Hg (95% confidence interval: 5.55, 7.63), respectively. Medication burden was reduced by ~1.0 medication at 6 to 18 months and 1.2 medications at 36 to 60 months. Adverse events reported in more than 5% of participants were progression of pre-existing cataract/cataract surgery and loss of best-corrected visual acuity but these rates were no different to those reported in comparator medical therapy study arms.

CONCLUSIONS

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.