Subvisible Laser Trabeculoplasty in Medically Treated Open-angle Glaucoma: a Randomized Three-arm Comparison of Selective, Micropulse and Pattern Delivery Protocols.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 90
- 试验地点
- 1
- 主要终点
- Intraocular pressure at 6 months
研究概览
简要总结
This randomized, single-centre, three-arm trial compared three subvisible laser trabeculoplasty delivery protocols in eyes with open-angle glaucoma already receiving intraocular pressure (IOP)-lowering medication: selective laser trabeculoplasty (SLT, 3-nanosecond pulses), micropulse laser trabeculoplasty (MLT, 577 nm with 15% duty cycle), and pattern laser trabeculoplasty (PLT, 5-ms pattern delivery). Ninety eyes of 90 patients were allocated 1:1:1 to a single 360-degree session and followed for 6 months. The primary outcome was IOP at 6 months, with an equivalence margin of +/-2.0 mmHg prespecified for pairwise comparisons. Secondary outcomes were percentage IOP change, number of IOP-lowering medications, cumulative treatment success (IOP reduction of at least 20% from baseline without an increase in medications), and adverse events. Outcome assessment was performed by a second ophthalmologist masked to allocation and to clinical history.
详细描述
Background and rationale
Laser trabeculoplasty is an established first-line and adjunctive treatment in open-angle glaucoma. Three subvisible delivery protocols are in clinical use and differ substantially in the physics of energy delivery: selective laser trabeculoplasty (SLT) uses 3-nanosecond pulses titrated to microbubble formation; micropulse laser trabeculoplasty (MLT) uses a 577-nm envelope chopped at a low duty cycle; pattern laser trabeculoplasty (PLT) uses short-exposure, high-density automated patterns. Evidence comparing them is indirect: SLT has been compared with medication in randomized and registry studies, SLT and MLT have been compared in retrospective series and in meta-analyses concluding non-inferiority, and each modality has been compared separately against medical therapy. No trial had compared all three protocols head to head in the same cohort under a single protocol.
Objectives
The trial was designed to determine whether the three subvisible delivery protocols differ in IOP reduction and in treatment success at 6 months in eyes with open-angle glaucoma already receiving medical therapy.
Design and setting
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
盲法说明
Participants and the treating surgeon were not masked to allocation, which is not feasible when the three lasers differ in console and audible signature. All intraocular pressure measurements and anterior segment examinations were performed by a second ophthalmologist masked to allocation and to clinical history. Medication changes were decided by the unmasked treating physician, so masking did not extend to the co-intervention.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •adults with primary or secondary open-angle glaucoma.
- •gonioscopically open angle confirmed by gonioscopy in the study eye.
- •receiving intraocular pressure-lowering medication at entry, with an indication for subvisible laser trabeculoplasty according to standard practice at the unit (IOP inadequately controlled on medical therapy, intolerance of medical therapy, or both).
- •written informed consent.
排除标准
- •previous laser trabeculoplasty, iridotomy or iridoplasty.
- •corneal disease precluding visualization of the trabecular meshwork or reliable applanation tonometry.
- •previous intraocular surgery other than uncomplicated cataract extraction.
- •systemic medication known to affect intraocular pressure.
- •pregnancy.
研究组 & 干预措施
Selective laser trabeculoplasty (SLT)
Single 360-degree session of selective laser trabeculoplasty with 3-nanosecond pulses, approximately 100 non-overlapping 400-micrometre spots, pulse energy titrated to visible microbubble formation in approximately 50% of applications up to a maximum of 1.4 mJ per pulse.
干预措施: Selective laser trabeculoplasty (Device)
Micropulse laser trabeculoplasty (MLT)
Single 360-degree session of micropulse laser trabeculoplasty at 577 nm, 1000 mW, 300-ms envelope, 300-micrometre spot, 15% duty cycle.
干预措施: Micropulse laser trabeculoplasty (Device)
Pattern laser trabeculoplasty (PLT)
Single 360-degree session of pattern laser trabeculoplasty at 577 nm: power titrated with 10-ms pulses until light blanching of the meshwork, then exposure shortened to 5 ms, with 100-micrometre spots delivered in 32 automatically rotating arc-shaped patterns of three rows of 13 spots, zero spacing, for approximately 1250 spots over 360 degrees.
干预措施: Pattern laser trabeculoplasty (Device)
结局指标
主要结局
Intraocular pressure at 6 months
时间窗: 6 months after treatment
Intraocular pressure (mmHg) measured by Goldmann applanation tonometry at the same time of day (+/- 1 hour) by an assessor masked to allocation. At every visit three consecutive readings were taken and their arithmetic mean used in the analysis. The treatment effect was the adjusted mean difference in 6-month intraocular pressure between each pair of treatment groups, estimated by analysis of covariance with baseline intraocular pressure as a covariate; a difference of +/-2.0 mmHg was prespecified as the equivalence margin.
次要结局
- Percentage change in intraocular pressure from baseline(1 day, 1 week, 1 month, 3 months and 6 months after treatment)
- Number of intraocular pressure-lowering medications(1 week, 1 month, 3 months and 6 months after treatment)
- Cumulative treatment success(from month 1 through 6 months after treatment)
- Adverse events, including postoperative intraocular pressure spike(from treatment through 6 months)
研究者
Daniele Veritti
Prof.
University of Udine