Clinical Outcomes of Small-incision Lenticule Extraction (SMILE) Using Vector Planning Method.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 114
- 试验地点
- 2
- 主要终点
- Uncorrected Distance Vision Acuity at each time point between the two groups.
研究概览
简要总结
In the past two decades, the femtosecond laser (FSL) technology has been introduced in the corneal refractive surgery filed, and brought a remarkable innovation. It can make tissue dissection through photodisruption and plasma cavitation. Initially, the FSL was used predominantly to make a corneal flap when performing laser in situ keratomileusis (LASIK), which is followed by stromal ablation using excimer laser. A new surgical technique called femtosecond lenticule extraction (FLEx) has been developed that uses only FSL to dissect two interfaces to create refractive lenticule and then remove it, which is very similar with LASIK. Small incision lenticule extraction (SMILE) which is the advanced form of all-in-one FSL refractive technique does not make a corneal flap rather make small incision where the separated refractive lenticule is removed through, and the upper part of the corneal tissue is called cap. Since the clinical outcomes of SMILE were firstly published in 2011, SMILE has been widely used for correction of myopia or myopic astigmatism worldwide. SMILE provides excellent visual outcomes and has advantages including a lesser decrease in corneal sensitivity and absence of flap related complications compared to LASIK.
The vector planning method is newly developed astigmatism correction method, which combines refraction astigmatism in 60 % emphasis and corneal astigmatism in 40 % emphasis. The vectorial difference between corneal astigmatism and refractive cylinder at the corneal plane is ocular residual astigmatism (ORA). In normal eyes treated for myopic astigmatism, the ORA typically ranges from 0.73 to 0.81 D. The eyes with high ORA resulted in inferior clinical outcomes after corneal refractive surgery including LASIK, LASEK, and SMILE. The vector planning method was effective in LASIK according to previous study. Therefore we try to confirm the efficacy of vector planning method in SMILE.
详细描述
Enrollment period : 6 months after IRB approval Participants : The subjects over 20 years old, who visited Severance hospital and Eyereum eye clinic for SMILE surgery with myopic astigmatism. The participants who satisfies criteria, and who can be monitored at all times during each period of observation after surgery are included in the study.
Methods: The subjects are randomly divided into two groups. One group underwent SMILE surgery using manifest refraction based planning, and the other group underwent SMILE surgery using vector planning. Before surgery, all patients underwent a detailed ophthalmological examination that included evaluation of logarithm of the minimum angle of resolution (logMAR) uncorrected-distance visual acuity (UDVA) and CDVA, manifest refraction, slit-lamp examination (Haag-Streit, Köniz, Switzerland), keratometry, and Scheimpflug-based corneal topography (Pentacam HR, Oculus). Dynamic corneal response (DCR) parameters were examined using Corvis ST. Corneal wavefront aberrations were measured using Keratron Scout (Optikon 2000, Rome, Italy). All examinations were repeated at 1, 3, and 6 months after surgery.
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
- None
入排标准
- 年龄范围
- 20 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age of 20 years or older.
- •Who is willing to get SMILE surgery
排除标准
- •Severe ocular surface disease
- •Any corneal disease, cataract, glaucoma, macular disease, or previous history of intraocular or corneal surgery
- •Patients with suspicion of keratoconus on corneal topography
结局指标
主要结局
Uncorrected Distance Vision Acuity at each time point between the two groups.
时间窗: postoperative 6 months
Uncorrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
Corrected Distance vision Acuity at each time point between the two groups.
时间窗: postoperative 6 months
Corrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
次要结局
- Coma aberration at each time point between the two groups.(6 months)
- Coma aberration changes from baseline at each postoperative time point between the two groups.(6 months)
- Total higher order aberration at each time point between the two groups.(6 months)
- Total higher order aberration changes from baseline at each postoperative time point between the two groups.(6 months)
- Spherical aberration at each time point between the two groups.(6 months)
- Spherical aberration changes from baseline at each postoperative time point between the two groups.(6 months)