Evaluating the Effect of Optical Zones on Correction for SMILE: Vector Analysis

Myopia Clinical Trial

Official title:

Evaluating the Effect of Optical Zones on Myopia and Astigmatism Correction in SMILE: Vector Analysis

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05017376
• Other study ID #: TJYYLL-202034
• Status: Completed
• Start date: August 1, 2020
• Est. completion date: August 1, 2021

Study information

• Verified date: August 2021
• Source: Tianjin Eye Hospital
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Evaluate the effect of the size of optical zones (OZ) on myopia and astigmatism correction in small incision lenticular extraction.

Description:

To retrospectively study whether different surgical optical zone sizes affect the correction of diopter and astigmatism in myopia patients. Divided into 2 groups according to the diameter of the optical zone. The vector analysis method was used to analyze the changes and errors of astigmatism in TR and SIR after operation. Generalized Estimation Equation (GEE) model is used for multiple regression analysis to evaluate the potential factors related to the error value.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 140
• Est. completion date: August 1, 2021
• Est. primary completion date: December 31, 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 45 Years

Eligibility

Inclusion Criteria:

• no ocular conditions

• normal topography

• central corneal thickness, >500µm

• residual stromal thickness, >280 µm

• pupil diameter, 2.78-4.9 mm (average, 3.76±0.43 mm);

Exclusion Criteria:

• history of intraocular surgery

• pupil diameter, >4.9 mm or <2.78mm

• keratoconus or corneal ectasia

Related Conditions & MeSH terms

• Myopia

Intervention

Procedure:
• small incision lenticular extraction
In patients with the same degree of myopia, different optical zones were designed for operation

Locations

Country	Name	City	State
China	Tianjin Eye Hospital	Tianjin

Sponsors (1)

Lead Sponsor	Collaborator
Tianjin Eye Hospital

Country where clinical trial is conducted

China, 

References & Publications (2)

Dishler JG, Slade S, Seifert S, Schallhorn SC. Small-Incision Lenticule Extraction (SMILE) for the Correction of Myopia with Astigmatism: Outcomes of the United States Food and Drug Administration Premarket Approval Clinical Trial. Ophthalmology. 2020 Aug — View Citation

Moshirfar M, Thomson AC, West WB Jr, Hall MN, McCabe SE, Thomson RJ, Ronquillo YC, Hoopes PC. Initial Single-Site Experience Using SMILE for the Treatment of Astigmatism in Myopic Eyes and Comparison of Astigmatic Outcomes with Existing Literature. Clin O — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	astigmatic changes	Observe the effect on changes in astigmatism by target induced astigmatism (TIA) versus surgically induced astigmatism (SIA)	2021.03
Primary	error value	Target refraction (TR) and surgically induced refraction (SIR) under different optical zones	2021.04