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Clinical Trials/NCT07260786
NCT07260786CompletedNot Applicable

A Study on the Correlation Between Visual Quality After SMILE and LASEK Procedures and the Visual Conduction Pathways in Patients With Moderate to Low Myopia

yuhao shao1 site in 1 country100 target enrollmentStarted: January 1, 2022Last updated:
Conditions

Trial Snapshot

Phase
Not Applicable
Status
Completed
Sponsor
Enrollment
100
Locations
1
Primary Endpoint
Contrast sensitivity

Study Overview

Brief Summary

  1. Study the changes in subjective visual quality, contrast sensitivity, and total ocular aberrations of patients with low-to-moderate myopia after SMILE and LASEK surgeries at different age groups;
  2. Evaluate the effects of SMILE and LASEK surgeries on the visual conduction pathway PVEP in patients with refractive errors of different age groups;
  3. Clarify the correlations between subjective and objective visual quality after SMILE and LASEK surgeries in patients with refractive errors of different age groups and PVEP.

Study Design

Study Type
Observational
Observational Model
Case Control
Time Perspective
Prospective

Eligibility Criteria

Ages
18 Years to 50 Years (Adult)
Sex
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  • Patients with refractive errors who were scheduled to undergo SMILE surgery and LASEK surgery were selected. The preoperative equivalent spherical diopter (SE) of the affected eye was less than -6D. The surgical plan was based on voluntary principle and was divided into the SMILE group and the LASEK group. Each surgical group was further divided according to age into groups of ≤ 20 years old, 21-30 years old, 31-40 years old, and ≥ 41 years old. Each group consisted of 35 patients. There were no significant differences in gender, equivalent spherical diopter (SE), optical zone, and preoperative best corrected visual acuity among the groups.

Exclusion Criteria

  • The nearsightedness has increased by more than 1D in the past two years. Severe dry eye syndrome, keratoconus, glaucoma, history of eye surgery, severe systemic connective tissue or autoimmune diseases

Outcomes

Primary Outcomes

Contrast sensitivity

Time Frame: Before the operation, 1 week after the operation, 1 month after the operation, 3 months after the operation, 6 months after the operation

Under sufficient correction conditions, dark adaptation lasted for 10 minutes. Using the CSV-1000 contrast sensitivity tester at a distance of 3 meters, under the conditions of bright vision (85 cd/m ²), bright glare (135 lx), dark vision (3 cd/m ²), and dark glare (28 lx) respectively, Test the highest CS level that can be distinguished at 3, 6, 12 and 18 c/d spatial frequencies one by one. At each spatial frequency, the examinee needs to point out the bar grid sight in the upper and lower two circular sight targets and report the direction of the bar grid. After the result is correct, gradually reduce the bar grid contrast until the examinee can no longer recognize it. The inverse of the lowest recognizable contrast at this time is the contrast sensitivity. Record in logarithmic units according to the grade value conversion table.

VEP

Time Frame: Before the operation, 1 week after the operation, 1 month after the operation, 3 months after the operation, 6 months after the operation

The VEP examination was repeated forN75 and P100. N75 latency and P100 amplitude and latency scores were calculated on the average waveform. It required manual definition of the lowest negative peak (N75) before P100 peak. Amplitude was scored as the difference between these two points and latency was scored as the time difference between N75 lowest peak or P100 peak and stimulus onset.

Secondary Outcomes

No secondary outcomes reported

Investigators

Sponsor
yuhao shao
Sponsor Class
Other
Responsible Party
Sponsor Investigator
Principal Investigator

yuhao shao

DR

Tongji University

Study Sites (1)

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