One-Year Follow-Up of Clinical and Tomographic Parameters After Conventional (3 mW/cm² × 30 Min) Versus Accelerated (9-10 mW/cm² × 10 Min) Epi-Off Corneal Collagen Cross-Linking
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Change in ABCD-A from baseline to 12 months
研究概览
简要总结
Prospective, observational (consecutive eligible eyes) continuation of a previously published 6-month cohort from the same center, extending follow-up to 12 months. Patients with progressive keratoconus received either conventional (CXL30: 3 mW/cm² × 30 min) or accelerated (CXL10: 9 mW/cm² × 10 min) epi-off CXL as part of routine clinical care. Assignment to CXL30 or CXL10 was at the discretion of the treating surgeon; no prospective allocation or randomization was performed. Outcomes included ABCD grading metrics (ABCD-A/B), Kmax, anterior/posterior radii of curvature (ARC/PRC), thinnest pachymetry, and visual acuity at 12 months. The primary objective was to evaluate one-year stabilization/remodeling and compare anterior/posterior responses between protocols.
详细描述
This prospective, single-center observational cohort extends the follow-up of a previously reported 6-month series from the same center to a 12-month horizon. The study population comprises consecutive patients with progressive keratoconus managed with standard-of-care, epi-off corneal collagen cross-linking (CXL) at the University Hospital Centre Zagreb. Patients were treated according to routine clinical decision-making by the attending surgeon; no prospective allocation or randomization to a protocol was performed. In routine care, some eyes underwent conventional CXL30 (Dresden-type; UVA 370 nm, 3 mW/cm² for 30 min) and others underwent CXL10 (accelerated; UVA 370 nm, 9 mW/cm² for 10 min). Riboflavin 0.1% solution was used per institutional practice. All procedures were epi-off.
Rationale. While both conventional and accelerated CXL are widely used in daily practice, comparative one-year data that integrate tomographic metrics from the ABCD grading system with traditional surrogates (e.g., Kmax) help clarify the balance between anterior corneal flattening, posterior remodeling, and pachymetric behavior under real-world conditions. This observational design captures effectiveness and safety without altering clinical decision pathways.
Design and cohorts. Consecutive eligible eyes were enrolled at the time of surgery and followed prospectively at baseline (day of surgery) and 1, 3, 6, and 12 months. Two observational cohorts are defined post hoc by the protocol actually received in standard care:
CXL30 (Conventional): continuous UVA 3 mW/cm² × 30 min (Dresden-type).
CXL10 (Accelerated): continuous UVA 9 mW/cm² × 10 min.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Progressive keratoconus documented on serial Scheimpflug tomography within the prior 12 months (ABCD/K-metrics and/or pachymetry).
- •Clear corneal axis (no visually significant scarring).
- •Corneal thickness 370 μm or more
排除标准
- •No central corneal scars, prior chemical burns, severe corneal infection, or ocular surface disease.
- •No pregnancy and lactation during treatment.
结局指标
主要结局
Change in ABCD-A from baseline to 12 months
时间窗: 12 months
Belin ABCD parameter A = A stage (ordinal severity stage); Belin ABCD keratoconus grading system (A = anterior corneal radius of curvature at the thinnest point; B = posterior corneal radius of curvature at the thinnest point; C = thinnest corneal pachymetry; D = distance best-corrected visual acuity). minimum value 0, maximum value 4 (ordinal scale 0-4) higher score means worse outcome
次要结局
- Change in thinnest pachymetry from baseline to 12 months(12 months)
- Change in UDVA and BCVA from baseline to 12 months(12 months)
- Change in Kmax from baseline to 12 months(12 months)
- Change in ARC from baseline to 12 months(12 months)
- Change in PRC from baseline to 12 months(12 months)
研究者
Iva Bešlić
Medical Doctor, Ophtalmology and Optometrist Specialist, FEBO
Clinical Hospital Centre Zagreb