My MIGS of Choice, with Sally Ameen

In the rapidly advancing field of ophthalmology, innovations in surgical techniques are paramount for improving patient outcomes. One of the most reliable procedures that glaucoma surgeons use is the iStent, which continues to offer significant utility in clinical practice because of how well it can manage intraocular pressure (IOP) in patients.The iStent is a microscopic, FDA-approved device implanted into the eye either during cataract surgery or as a standalone procedure. The smallest implant currently used in the human body, the main function of the iStent is to create a permanent opening in the trabecular meshwork, the eye's natural drainage system. This allows for better outflow of aqueous humor, which in turn helps to reduce intraocular pressure. By doing so, it helps to control the progression of glaucoma.

Benefits to iStent surgery
 

First and foremost, it is minimally invasive, which means shorter recovery times and fewer complications compared to traditional glaucoma surgeries. It effectively lowers intraocular pressure by improving aqueous outflow, which is crucial in slowing the progression of glaucoma and preserving vision. Additionally, for patients who need both cataract and glaucoma surgery, the iStent can be implanted at the same time as cataract surgery. This dual approach provides comprehensive care in a single procedure. Many patients also find that they can reduce their reliance on glaucoma medications after having the iStent implanted, which simplifies their treatment regimen and improves their overall quality of life.

Comparison with other MIGS options
 

My preference for the iStent stems from its long-standing presence in the market. It has been available for the longest time compared to other MIGS (minimally invasive glaucoma surgery) options, which means we have a wealth of data and extensive clinical testing to back up its efficacy and safety. This extensive track record translates into a high level of confidence in its performance. Studies consistently show that the iStent is effective in lowering intraocular pressure and reducing the progression of glaucoma. Furthermore, the safety profile of the iStent is outstanding, which is paramount when considering surgical options for my patients.

In one study, a significantly higher proportion of iStent inject with cataract surgery (INJ) eyes (75.8 percent) than cataract surgery-alone (CS) eyes (61.9 percent) achieved a ≥ 20 percent  reduction in medication-free diurnal intraocular pressure (DIOP) from baseline at 24 months (p=0.005), and the mean reduction in medication-free DIOP from baseline to 24 months was significantly greater in treatment versus control eyes (p<0.001), respectively (1).

Furthermore, iStent-injected eyes reduced their mean medication burden by 75 percent (versus 47 percent in CS eyes), with 84 percent of stent eyes becoming medication-free at two years (vs. 67 percent  of control eyes), and a 50 percent lower final mean medication burden in stent eyes than in control eyes.

Safety was excellent in the iStent inject treatment group, comparable to phacoemulsification alone. This included results for best spectacle-corrected visual acuity (BSCVA), visual field MD, C:D ratio, and endothelial cell stability. There were no unanticipated adverse events and no cases of significant inflammatory responses, myopic shift, choroidal hemorrhage or effusion, hypotony, stent dislocation or migration, significant hyphema, corneal decompensation, shallow anterior chamber, cyclodialysis, or endophthalmitis (1).

Patient feedback
 

The outcomes have been very encouraging. Patients often report significant improvements in their quality-of-life post-surgery, with many experiencing enhanced vision and a reduced need for glaucoma medications. Additionally, the peace of mind that comes from knowing their glaucoma is being effectively managed cannot be overstated.

At eight years postoperative, IOP reduced by 26 percent from 19.2 ± 3.9 mmHg preoperatively to 14.2 ± 2.4 mmHg (P < 0.001), 91.1 percent  of eyes achieved IOP ≤ 18 mmHg (vs. 51.6 percent preoperatively), 69.6 percent  of eyes achieved IOP ≤ 15 mmHg (vs. 14.5 percent  preoperatively), and 25 percent  of eyes achieved IOP ≤ 12 mmHg (vs. 1.6 percent  preoperatively). Medication use decreased by 17.9 percent  from 2.8 ± 1.1 preoperatively to 2.3 ± 1.2 (P = 0.018). Surgical success was 90 percent, as six eyes underwent subsequent glaucoma surgeries. Safety measures of BCVA, cup-to-disc ratio (CDR), retinal nerve fiber layer (RNFL) thickness, and GC-IPL thickness remained stable through eight years postoperative. Visual field mean deviation (VF-MD) remained stable until postoperative year five and subsequently progressed according to the natural history of glaucomatous disease (2).

For me, these positive outcomes are a testament to the efficacy and safety of the iStent.

The author has no financial conflict or disclosure with any procedure or product in this article.