Singh Inder Paul, Sarkisian Steven, Hornbeak Dana, Katz L Jay, Samuelson Thomas
The Eyes Centers of Racine & Kenosha, Racine, WI, USA.
Oklahoma Eye Surgeons, Oklahoma City, OK, USA.
Clin Ophthalmol. 2021 Aug 3;15:3231-3240. doi: 10.2147/OPTH.S316270. eCollection 2021.
To examine effectiveness outcomes stratified by preoperative disease burden in the pivotal trial of iStent with cataract surgery (INJ) vs cataract surgery alone (CS).
Prospective, 3:1 randomized, single-masked, concurrently-controlled, multicenter trial enrolling 505 subjects with cataract and mild-to-moderate primary open-angle glaucoma who underwent iStent implantation with phacoemulsification or phacoemulsification alone, and were followed for 2 years including annual medication washouts. Post hoc stratification was completed for baseline mean diurnal intraocular pressure (BL DIOP; Low-DIOP <25mmHg, Mid-DIOP ≥25 to <30 mmHg, High-DIOP ≥30mmHg) and preoperative medication burden (Low-Med 1 medication, Mid-Med 2 medications, High-Med ≥3 medications).
The 24-month primary and secondary effectiveness endpoints were met, with significant treatment-over-control differences in percent of eyes achieving ≥20% unmedicated DIOP reduction and in unmedicated DIOP reduction, respectively. In subgroup analyses, the proportions of INJ eyes achieving the primary endpoint remained steady across all BL DIOP (75.4%, 77.1%, 74.4% in Low/Mid/High-DIOP strata, respectively) and preoperative medication levels (76.8%, 70.8%, 79.7% in Low/Mid/High-Med strata, respectively); meanwhile, the proportions of CS eyes diminished with higher BL DIOP (64.5%, 63.6%, 33.3%, respectively) and more medications (69.0%, 63.3%, 29.4%, respectively). Regarding secondary effectiveness, postoperative DIOP reduction increased with higher BL DIOP in INJ eyes (6.2mmHg, 7.8mmHg, 9.8mmHg, respectively) but plateaued in CS eyes (5.2mmHg, 5.8mmHg, 5.4mmHg, respectively). INJ eyes also had consistent DIOP reduction regardless of preoperative medication burden (6.8mmHg, 6.7mmHg, 7.8mmHg, respectively), while DIOP reduction diminished with more medications in CS eyes (6.1mmHg, 5.0mmHg, 3.3mmHg, respectively). Safety was favorable, comparable to phacoemulsification alone.
Significant IOP reductions occurred across all levels of BL DIOP and preoperative medication burden in iStent eyes. DIOP reductions increased with higher BL DIOP and remained stable across all levels of preoperative medication burden, suggesting the device's potential utility in more medically challenging cases.
在iStent植入联合白内障手术（INJ）与单纯白内障手术（CS）的关键试验中，按术前疾病负担对疗效结果进行分析。
一项前瞻性、3:1随机、单盲、同期对照、多中心试验，纳入505例患有白内障和轻至中度原发性开角型青光眼的受试者，这些受试者接受了iStent植入联合超声乳化术或单纯超声乳化术，并随访2年，包括每年的药物洗脱期。对基线平均日间眼压（BL DIOP；低眼压<25mmHg，中眼压≥25至<30mmHg，高眼压≥30mmHg）和术前药物负担（低药物负担1种药物，中药物负担2种药物，高药物负担≥3种药物）进行事后分层。
达到了24个月的主要和次要疗效终点，在实现≥20%非药物性眼压降低的眼百分比和非药物性眼压降低方面，治疗组与对照组有显著差异。在亚组分析中，INJ组达到主要终点的眼比例在所有BL DIOP水平（低/中/高眼压层分别为75.4%、77.1%、74.4%）和术前药物水平（低/中/高药物负担层分别为76.8%、70.8%、79.7%）中保持稳定；同时，CS组眼的比例随着BL DIOP升高（分别为64.5%、63.6%、33.3%）和药物增多（分别为69.0%、63.3%、29.4%）而降低。关于次要疗效，INJ组术后眼压降低随着BL DIOP升高而增加（分别为6.2mmHg、7.8mmHg、9.8mmHg），但CS组趋于平稳（分别为5.2mmHg、5.8mmHg、5.4mmHg）。无论术前药物负担如何，INJ组眼的眼压降低均保持一致（分别为6.8mmHg、6.7mmHg、7.8mmHg），而CS组眼的眼压降低随着药物增多而减少（分别为6.1mmHg、5.0mmHg、3.3mmHg）。安全性良好，与单纯超声乳化术相当。
iStent植入组在所有BL DIOP水平和术前药物负担水平上均出现了显著的眼压降低。眼压降低随着BL DIOP升高而增加，并且在所有术前药物负担水平上保持稳定，这表明该装置在更具医学挑战性的病例中具有潜在应用价值。
