Comparison of Epi-off and Epi-on Photorefractive Intrastromal Crosslinking (PiXL) for Progressive Keratoconus
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 32
- 试验地点
- 2
- 主要终点
- Maximal keratometry (Kmax)
研究概览
简要总结
The purpose of this study is to evaluate the efficacy, safety and postoperative ocular discomfort by comparing individually customized Photorefractive intrastromal crosslinking (PiXL) for progressive Keratoconus. The study compares two different protocols, PiXL with corneal epithelium debridement (Epi-off) and PiXL without epithelium debridement in high oxygen environment (Epi-on), with the hypothesis that Epi-on gives less postoperative ocular discomfort.
详细描述
The study is designed as a prospective, single-masked intraindividually comparing randomized clinical trial involving participants of both genders aged 18-35 years with Keratoconus planned for routine corneal crosslinking at the Department of Ophthalmology, Umeå University Hospital, Umeå, Sweden. The study includes 32 participants with bilateral Keratoconus, receiving Epi-off PiXL (n=32) in one eye and Epi-on PiXL in high oxygen environment (n=32) in the fellow eye. The participants are randomized to epi-on PiXL utilizing block randomization with a sample size of 16 in each block; 16 right eyes and 16 left eyes. All participants are informed about the procedures before consenting to participate in the study.
At baseline, before treatment, each eye is examined with slit-lamp microscopy, subjective refraction, determination of uncorrected (UCVA), low contrast visual acuity at 2.5 percentage contrast and 10 percentage contrast and best corrected (BSCVA) visual acuities using the LogMAR fast protocol and intraocular pressure (IOP) using Goldmann applanation tonometry. Under standardized, mesopic light conditions each eye is evaluated by keratometry readings and central corneal thickness using Schemipflug camera measurements, Pentacam HR® (Oculus, Inc. Lynnwood, WA).
Endothelial cellcount is assessed (SP-2000P, Topcon, Inc) and total ocular wavefront is measured with iTrace (Tracey Technologies, Inc.).
Ocular discomfort is subjectively evaluated in each eye by a specific visual analogous rating scale at 4h, 8h 24h and thereafter daily up to 1 week postoperatively.
All the above mentioned examinations are repeated at 1, 3, 6, 12 and 24 months after treatment. At 1 day and 1 week after treatment, solely UCVA, Auto-refractor measurements and slit-lamp examination are evaluated.
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 (Participant)
盲法说明
The participants are not aware which eye will receive the Epi-off PiXL treatment and which eye will receive the Epi-on PiXL treatment.
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients planned for corneal crosslinking.
- •Progressive keratoconus documented with a consistent decrease of best corrected visual acuity with no other explanation, an unquestionable historical progression, or a progression documented with the Pentacam Scheimpflug camera with at least 2 of the following: progressive anterior and/or posterior corneal steepening and/or progressive corneal thinning and/or increased rate of corneal thickness change from the periphery to the center.
- •A keratoconus diagnosis based on abnormal posterior elevation, abnormal corneal thickness distribution and clinical noninflammatory corneal thinning using the "Belin/Ambrósio enhanced ectasia" measurements of the Pentacam Scheimpflug camera.
- •Minimum corneal thickness of 400 µm at the thinnest point before epithelial removal.
- •18-35 years of age
- •No ocular abnormalities except keratoconus
- •No previous ocular surgery
- •No cognitive insufficiency interfering with the informed consent.
排除标准
- •Age under 18 or over 35
- •Any corneal abnormalities except keratoconus
- •Pregnancy or lactation
- •Previous ocular surgery
- •Cognitive insufficiency
结局指标
主要结局
Maximal keratometry (Kmax)
时间窗: 1 month, 3 months, 6 months, 12 months and 24 months after treatment
Kmax assessed with the Pentacam HR Scheimpflug camera, Diopters.
次要结局
- Uncorrected distance visual acuity (UDVA)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Mean keratometry (Kmean)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Subjective Ocular Discomfort Scores(4 hours, 8 hours, 1 day, 2 days, 3 days, 4 days, 5 days, 6 days and 7 days after treatment)
- Manifest spherical equivalent (MRSE)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Change from baseline in ocular wavefront aberrometry(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Endothelial cell density (ECC)(24 months after treatment)
- Best corrected visual acuity (BCVA)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Low contrast visual acuity (LCVA)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Central corneal thickness (CCT)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
- Intraocular pressure (IOP)(1 month, 3 months, 6 months, 12 months and 24 months after treatment)
研究者
Anders Behndig
Principal Investigator
Umeå University