International Multicenter Study on SMILE Surgery

NCT ID: NCT02844556

Last Updated: 2018-05-04

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 1000 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-09-30
• Study Completion Date: 2019-12-31

Brief Summary

The purpose of this study is to carry out an international multicenter trial to get more convincing and valuable results of the SMILE surgery and compare the outcomes between the SMILE surgery and the FS-LASIK (femtosecond laser assisted-laser in situ keratomileusis) surgery.

The investigators hope to investigate the differences between the SMILE and the FS-LASIK surgery comprehensively, including the comparison of visual acuity, refraction, the correction of cylindrical diopter, the high order aberrations, the corneal biomechanics, the corneal ectasia, the characteristics of the changes of central corneal thickness and the complications. To meet the demands of a multi center trial, all the examination equipments should be same in each center, and this will limit the variations within a study

Detailed Description

Hypothesis: To compare the novel refractive surgery (SMILE, the intervention group) with traditional refractive surgery (FS-LASIK, the control group) in terms of visual acuity, the higher order aberrations, corneal biomechanical parameters and the complications. SMILE surgery might offer some advantages in some aspects compared with FS-LASIK surgery.

Study program

The procedures of the study are listed as follows:

All the participants accept the refractive surgery which were selected at first, and patients' routine postoperative examinations included UCVA, BCVA, slit lamp microscopy, non-contact IOP, corneal topography with the Scheimpflug tomography system, ocular higher order aberrations using the WASCA analyzer (Carl Zeiss Meditec AG), corneal biomechanical properties acquired by the Ocular Response Analyzer and/or the Corvis ST (Corvis ST, OCULUS, Wetzlar, Germany) at 1 week, 1 month, 3 months and 6 months follow-up periods after surgery.

Statistics:

Patients who have decided to choose the SMILE surgery or the FS-LASIK will be selected as participants. The propensity matching method will be used to choose proper cases for the two groups. The propensity matching method can be calculated by SPSS software. The independent variables include: the central corneal thickness (CCT), the Km (mean Pentacam keratometry), the spherical diopter (from manifest refraction), and the cylindrical diopter (from manifest refraction), the UCVA, the BCVA, the corneal resistance factor (CRF) and the corneal hysteresis (CH) (if the investigator have the Ocular Response Analyzer) of the cornea at preoperative. The closest score of eyes in the two groups will be matched.

The data will be preserved by each site, and will be systematically collected and analyzed by TianjinEH center. The statistical expert Dr Hayes from American Pacific University will be the statistical consultant, and will also in charge of the sample size calculation, the instructor of statistical analysis, and the quality control.

Conditions

Refractive Error

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

SMILE surgery

Small incision lenticule extraction (SMILE) has become a novel and effective method for the correction of myopia and myopic astigmatism. It is a micro-invasive and flapless refractive procedure that has been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

Group Type: OTHER

SMILE surgery

Intervention Type: PROCEDURE

SMILE surgery and FS-LASIK surgery are both effective method for the correction of myopia and myopic astigmatism. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

FS-LASIK surgery

FS-LASIK surgery is femtosecond laser assisted- conventional refractive surgery and has also been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

Group Type: OTHER

FS-LASIK surgery

Intervention Type: OTHER

SMILE surgery and FS-LASIK surgery are both effective method for the correction of myopia and myopic astigmatism. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

Interventions

SMILE surgery

SMILE surgery and FS-LASIK surgery are both effective method for the correction of myopia and myopic astigmatism. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

Intervention Type: PROCEDURE

FS-LASIK surgery

SMILE surgery and FS-LASIK surgery are both effective method for the correction of myopia and myopic astigmatism. They have been proved to offer many advantages in terms of visual acuity, corneal sensitivity and corneal biomechanics compared with traditional refractive surgeries.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• be accompanied by a parent or guardian who is able to give informed consent as demonstrated by signing a record of informed consent;
• at baseline, be within the age range of 18 to 45 years old inclusive
• normal corneal morphology with no corneal nebula or corneal macula, the range of preoperative K2 (the steep curvature of the 3mm area at the center of cornea) from 38.0 to 47.0 diopter
• manifest spherical equivalent of -1.0 to -10.0 diopters (D)
• cylindrical diopter no more than -5.0D
• refractive diopter maintained stable for more than2 years
• preoperative BCVA≥0.8, and the scotopic pupil diameter≥5.0mm when measured by WASCA analyzer (Carl Zeiss Meditec AG)
• picked off soft contact lens for more than 2 weeks
• picked off RGP for more than 1 month
• preoperative corneal central thickness measured by Pentacam >500μm, non-contact IOP<21mmHg
• be willing to comply with the clinical trial visit schedule as directed by the investigator.

Exclusion Criteria

• any corneal diseases, corneal operations, eyes trauma or systemic diseases history; keratoconus or tendency of keratoconus
• corneal macula and obvious pannus; current enrolment in another clinical trial/research project.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 45 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Nethradhama Superspeciality Eye Hospital

OTHER

Sponsor Role: collaborator

Alexandria University

OTHER

Sponsor Role: collaborator

Belgian Ocular Laser Centre

OTHER

Sponsor Role: collaborator

Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

OTHER

Sponsor Role: collaborator

Jinan Mingshui Eye Hospital

OTHER

Sponsor Role: collaborator

Tianjin Eye Hospital

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Yan Wang, director

Role: STUDY_DIRECTOR

Tianjin Eye Hospital

Sri Ganesh, professor

Role: PRINCIPAL_INVESTIGATOR

Nethradhama Superspeciality Eye Hospital

Bernard Heintz, professor

Role: PRINCIPAL_INVESTIGATOR

Belgian Ocular Laser Centre

Osama Ibrahim, professor

Role: PRINCIPAL_INVESTIGATOR

Cornea Center, Alexandria University

Keming Yu, professor

Role: PRINCIPAL_INVESTIGATOR

Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

Yulin Lei, professor

Role: PRINCIPAL_INVESTIGATOR

Jinan Mingshui Eye Hospital

Locations

Tianjin Eye Hospital

Tianjin, , China

Site Status: RECRUITING

Countries

China

Central Contacts

Yan Wang, director

Role: CONTACT

wangyan7143@vip.sina.com

Facility Contacts

Yan Wang, director

Role: primary

wangyan7143@vip.sina.com

+86-02227305083

References

Wei S, Wang Y. Comparison of corneal sensitivity between FS-LASIK and femtosecond lenticule extraction (ReLEx flex) or small-incision lenticule extraction (ReLEx smile) for myopic eyes. Graefes Arch Clin Exp Ophthalmol. 2013 Jun;251(6):1645-54. doi: 10.1007/s00417-013-2272-0. Epub 2013 Feb 7.

Reference Type: BACKGROUND

PMID: 23389552 (View on PubMed)

Wang Y, Bao XL, Tang X, Zuo T, Geng WL, Jin Y. [Clinical study of femtosecond laser corneal small incision lenticule extraction for correction of myopia and myopic astigmatism]. Zhonghua Yan Ke Za Zhi. 2013 Apr;49(4):292-8. Chinese.

Reference Type: BACKGROUND

PMID: 23900086 (View on PubMed)

Wu D, Wang Y, Zhang L, Wei S, Tang X. Corneal biomechanical effects: small-incision lenticule extraction versus femtosecond laser-assisted laser in situ keratomileusis. J Cataract Refract Surg. 2014 Jun;40(6):954-62. doi: 10.1016/j.jcrs.2013.07.056. Epub 2014 Apr 18.

Reference Type: BACKGROUND

PMID: 24751146 (View on PubMed)

Li X, Wang Y, Dou R. Aberration compensation between anterior and posterior corneal surfaces after Small incision lenticule extraction and Femtosecond laser-assisted laser in-situ keratomileusis. Ophthalmic Physiol Opt. 2015 Sep;35(5):540-51. doi: 10.1111/opo.12226. Epub 2015 Jun 18.

Reference Type: BACKGROUND

PMID: 26087672 (View on PubMed)

Zhang J, Wang Y, Wu W, Xu L, Li X, Dou R. Vector analysis of low to moderate astigmatism with small incision lenticule extraction (SMILE): results of a 1-year follow-up. BMC Ophthalmol. 2015 Jan 24;15:8. doi: 10.1186/1471-2415-15-8.

Reference Type: BACKGROUND

PMID: 25618419 (View on PubMed)

Other Identifiers

Tianjin EH-SMILE

Identifier Type: -

Identifier Source: org_study_id