<p>iStent Trabecular Microbypass Stent Implantation with Phacoemulsification in Patients with Open-Angle Glaucoma: 6-Year Outcomes</p>

Abstract

Purpose: To investigate the long-term safety and efficacy of an iStent trabecular microbypass stent in combination with cataract surgery in eyes with primary open-angle glaucoma (POAG). Setting: Private practice; Sioux Falls, South Dakota. Design: Retrospective, consecutive case series. Methods: This case series included eyes implanted with a single trabecular microbypass stent in combination with phacoemulsification in patients with mild to severe POAG. Data were collected preoperatively and at day 1, week 1, month 1, and up to 6 years postoperatively. Primary outcome measures included mean intraocular pressure (IOP) and number of glaucoma medications. Safety was noted by assessing the incidence of IOP spikes and need for additional surgery. Results: The study comprised 411 eyes. Mean IOP was reduced to 14.9±4.2 mmHg compared to 18.8±5.6 mmHg at baseline at 6 years postoperative. The mean number of medications was reduced to 1.2±1.0 from 1.4±1.1 at baseline. In eyes with severe stage of disease, there was a mean IOP reduction >6 mmHg at 6 years postoperative. Eyes with baseline IOP ≥18 mmHg achieved a more robust reduction in IOP. Fifteen eyes underwent a secondary glaucoma procedure. There were no intra-or postoperative complications. Conclusion: Trabecular microbypass stent implantation in combination with cataract surgery provides a sustained IOP reduction in eyes with mild-to-severe POAG. The degree of IOP reduction was more significant in eyes with higher baseline IOP and severe stage of disease.

Treatment Success Across Different Levels of Preoperative Disease Burden: Stratified Two-Year Outcomes from the Pivotal Trial of iStent inject® Trabecular Micro-Bypass in Primary Open-Angle Glaucoma and Cataract

“…This trend also is widely recognized in glaucomatous eyes undergoing combined phacoemulsification and glaucoma procedures, 50,51 and specifically in eyes undergoing iStent or iStent inject implantation either with or without phacoemulsification. [15][16][17][18]26,27 In contrast to the predominant consensus in the literature, four recent non-controlled, non-randomized studies have suggested that success rates are higher in eyes with lower, rather than higher, disease burden: for example, in eyes with lower baseline IOP 44,52 or lower IOP during the first postoperative month; 45 lower number of preoperative medications; 44,45,52 or lower glaucoma severity according to VF MD. 45,53 However, attention must be paid to how these studies defined postoperative success; specifically, none of the studies' success criteria were adjusted for patients' preoperative IOP/medication burden or individual goals for surgery.…”

“…With up to 7 years of postoperative follow-up, iStent studies have often focused on patients with mild to moderate POAG undergoing cataract surgery, but an increasing number of studies have assessed iStent for different glaucoma types (eg, pseudoexfoliative, angle-closure, pigmentary), more advanced severity, standalone cases, and in combination with other procedures or stents. [11][12][13][14][15][16][17][18][19][20][21][22][23] The more recent iStent inject ® Trabecular Micro-Bypass (CE Mark 2010, FDA approval 2018) contains two stents that create two patent bypasses through the diseased trabecular meshwork. This device has been studied both with and without concomitant cataract extraction, and in studies with up to 5 years of follow-up.…”

“…[40][41][42][43] In addition, several publications have shown this IOP association following iStent or iStent inject implantation. [15][16][17][18]26,27 Fewer studies have evaluated the relationship between preoperative medication burden and postoperative IOP reduction. 44,45 However, to our knowledge, no MIGS pivotal trials to-date have specifically explored outcomes with stratification by preoperative IOP and medications.…”

Two-Year Comparative Outcomes of First- and Second-Generation Trabecular Micro-Bypass Stents with Cataract Surgery

“…The degree of postoperative IOP reduction also was greater in eyes with higher preoperative IOP, as has been shown previously. 10 , 12–14 , 21 Importantly, the outcomes in both groups were achieved in consecutive (all-comer) patients in the context of the surgeon’s clinical practice, with the patient population including different glaucoma subtypes and severities. The subgroup analysis of secondary glaucoma cases (PXG and PG), although limited in size, revealed favourable IOP and medication reductions, consistent with previously published larger studies of the iStent specifically in these populations.…”

5-year outcomes of single iStent (G1) trabecular microbypass implantation with phacoemulsification in moderately advanced primary open angle glaucoma

“…MIGS procedures are predicated on safety, can be combined with cataract surgery, as well as other MIGS procedures [ 8 , 9 ] without interfering with future surgical intervention [ 10 , 11 ]. Although the iStent has been extensively studied in patients with primary open-angle glaucoma (POAG) in the short-term [ 12 – 15 ] there are few studies reporting long-term data in these patients [ 16 , 17 ]. This study aims to evaluate the real-world long-term (5-year) safety and efficacy of single iStent (G1) in combination with micro-incision cataract surgery in patients with moderately advanced POAG.…”