Singapore National Eye Centre, Singapore, Singapore.
Trials. 2012 May 31;13:75. doi: 10.1186/1745-6215-13-75.
Small incision lenticule extraction or SMILE is a novel form of 'flapless' corneal refractive surgery that was adapted from refractive lenticule extraction (ReLEx). SMILE uses only one femtosecond laser to complete the refractive surgery, potentially reducing surgical time, side effects, and cost. If successful, SMILE could potentially replace the current, widely practiced laser in-situ keratomileusis or LASIK. The aim of this study is to evaluate whether SMILE is non-inferior to LASIK in terms of refractive outcomes at 3 months post-operatively.
METHODS/DESIGN: Single tertiary center, parallel group, single-masked, paired-eye design, non-inferiority, randomized controlled trial. Participants who are eligible for LASIK will be enrolled for study after informed consent. Each participant will be randomized to receive SMILE and LASIK in each eye. Our primary hypothesis (stated as null) in this non-inferiority trial would be that SMILE differs from LASIK in adults (>21 years old) with myopia (> -3.00 diopter (D)) at a tertiary eye center in terms of refractive predictability at 3 months post-operatively. Our secondary hypothesis (stated as null) in this non-inferiority trial would be that SMILE differs from LASIK in adults (>21 years old) with myopia (> -3.00 D) at a tertiary eye center in terms of other refractive outcomes (efficacy, safety, higher-order aberrations) at 3 months post-operatively. Our primary outcome is refractive predictability, which is one of several standard refractive outcomes, defined as the proportion of eyes achieving a postoperative spherical equivalent (SE) within ±0.50 D of the intended target. Randomization will be performed using random allocation sequence generated by a computer with no blocks or restrictions, and implemented by concealing the number-coded surgery within sealed envelopes until just before the procedure. In this single-masked trial, subjects and their caregivers will be masked to the assigned treatment in each eye.
This novel trial will provide information on whether SMILE has comparable, if not superior, refractive outcomes compared to the established LASIK for myopia, thus providing evidence for translation into clinical practice.
Clinicaltrials.gov NCT01216475.
小切口微透镜提取术或 SMILE 是一种新型的“无瓣”角膜屈光手术，它是从屈光性微透镜切除术（ReLEx）改编而来的。SMILE 仅使用一次飞秒激光即可完成屈光手术，有可能减少手术时间、副作用和成本。如果成功，SMILE 有可能取代目前广泛应用的激光原位角膜磨镶术（LASIK）。本研究的目的是评估 SMILE 在术后 3 个月的屈光效果是否不劣于 LASIK。
方法/设计：单中心、平行组、单盲、配对眼设计、非劣效性、随机对照试验。符合 LASIK 适应证的参与者在知情同意后将被纳入研究。每个参与者将被随机分配到每只眼接受 SMILE 和 LASIK。在这个非劣效性试验中，我们的主要假设（陈述为零假设）是，在一家三级眼科中心，SMILE 在近视（>-3.00 屈光度（D））成年人中，与 LASIK 在术后 3 个月的屈光预测方面没有差异。在这个非劣效性试验中，我们的次要假设（陈述为零假设）是，在一家三级眼科中心，SMILE 在近视（>-3.00 D）成年人中，与 LASIK 在术后 3 个月的其他屈光结果（疗效、安全性、高阶像差）方面没有差异。我们的主要结局是屈光预测，这是几个标准屈光结局之一，定义为术后等效球镜（SE）在目标值的±0.50 D 范围内的眼比例。随机化将使用计算机生成的无块或无限制的随机分配序列进行，通过将编号手术隐藏在密封信封中直到手术前才实施。在这个单盲试验中，受试者及其护理人员将对每只眼的分配治疗保持盲态。
这项新的试验将提供有关 SMILE 是否具有与 LASIK 相当（如果不是更好）的近视屈光效果的信息，从而为转化为临床实践提供证据。
Clinicaltrials.gov NCT01216475。
