Phacoemulsification vs phacoemulsification with micro‐bypass stent implantation in primary angle closure and primary angle closure glaucoma: A randomized single‐masked clinical study

Abstract

Importance: Primary angle closure glaucoma (PACG) is a major cause of irreversible visual impairment in Asia, but there is no published data on the effect of iStent on these patients. Background: To compare the efficacy and safety of combined phacoemulsification and iStent implantation with standard phacoemulsification in an Asian population.Design: A prospective, single-masked, randomized study in a public tertiary eye clinic. Participants: Patients with concomitant visually significant cataracts and primary angle closure (PAC) or PACG. Methods: Patients were randomized and underwent either phacoemulsification alone (phaco) or with concurrent iStent injection (phaco-iStent). Demographic and clinical data were collected.Main Outcome Measures: Complete and qualified success rates at 12 months were compared between both treatment arms. Results: Thirty-two patients were recruited between September 2015 and February 2016. All patients completed 12 months of follow-up. There was no statistically significant difference in preoperative IOP (phaco, 17.5 ± 3.1 mmHg; phaco-iStent, 18.6 ± 4.7 mmHg, P = .65) and 12-months postoperative IOP (phaco, 15.0 ± 2.5 mmHg; phaco-iStent, 14.7 ± 3.1 mmHg, P = .86) between both groups. Complete success rates were 43.8% (95% CI, 19.8-65.6) for the Phaco group and 87.5% (95% CI, 58.6-96.7) for the Phaco-iStent group (P = .01). Thinner preoperative optical coherence tomography (retinal nerve fibre layer) thickness (hazard ratio [HR] = 7.34 [95% CI, 1.53-35.30]) and phacoemulsification alone (HR = 0.93 [95% CI, 0.87-0.02]) were independent factors associated with failure to achieve complete success.

<p>iStent Trabecular Micro-Bypass Stent Implantation with Cataract Surgery in a Japanese Glaucoma Population</p>

“…To date, the safety and performance of iStent trabecular micro-bypass have been established by a breadth of studies evaluating the device, including in standalone implantation or in combination with cataract surgery or other MIGS procedures, in both single-and multiple-stent usage, in populations with various levels of disease severity, and in various subtypes of glaucoma and ocular hypertension. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] The stent has been widely adopted and studied by surgeons around the world. 43 However, iStent outcomes have not been as closely examined in Japanese populations.…”

“…They have been studied extensively and are established as a safe and effective option in various types of OAG with and without concomitant cataract surgery. However, relatively few studies have been completed in Japanese patients 11,23 or in NTG. 24,25 Japanese populations have a significantly higher prevalence of NTG than most other populations, accounting for >90% of OAG cases in Japan.…”

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

“…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.…”

Efficacy and safety of trabeculectomy versus peripheral iridectomy plus goniotomy in advanced primary angle-closure glaucoma: study protocol for a multicentre, non-inferiority, randomised controlled trial (the TVG study)

“…[13][14][15] After PEI, MIGS including goniotomy (GT), implantation of bypass and endocycloplasty can be performed just as in primary open-angle glaucoma with its advantages being having a safe profile, faster recovery and relatively few complications. [16][17][18] Additive IOP-lowering is thus obtained for advanced PACG. GT, the most popular type of MIGS, has been successfully adopted for PACG using Kahook Dual Blade, [19][20][21] Tanito Microhook, 22 23 or other microhooks or gonioscopy-assisted transluminal trabeculotomy.…”