Factors Influencing Subjective Visual Quality in Human Eyes

April 4, 2026 updated by: Tianjin Eye Hospital

Factors Influencing Subjective Visual Quality in Normal Human Eyes and Before and After Refractive Surgery

To assess subjective visual symptoms using the QoV questionnaire, measure pupil size using the Atongmu Pupillometer, measure wavefront aberrations using the OPD-Scan III Aberrometer, and measure/calculate the effective optical zone using the Pentacam system. The relationships between pupil size, higher-order aberrations (HOAs), effective optical zone after refractive surgery, and subjective visual symptoms will be explored.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

The sample size will be calculated using an appropriate sample size calculation formula. Using a random number table method, 1200 subjects scheduled for preoperative examination at the Refractive Surgery Center of Tianjin Eye Hospital between December 1, 2025, and May 1, 2026, will be randomly selected. Data including age, gender, spectacle wear status, uncorrected visual acuity (UCVA), spherical power, cylindrical power, intraocular pressure (IOP), mean keratometry (Km), corneal thickness, axial length, and degree of lens and vitreous opacities will be recorded. Pupil size under photopic, mesopic, and scotopic conditions will be measured using the Atongmu Pupillometer. Wavefront aberrations will be measured using the OPD-Scan III Aberrometer (OPD: Optical Path Difference). Subjects will complete the Quality of Vision (QoV) questionnaire.

Additionally, based on sample size calculation, using a random number table method, 300 subjects undergoing refractive surgery at the Refractive Surgery Center of Tianjin Eye Hospital between December 1, 2025, and May 1, 2026, will be randomly selected and prospectively followed up until 3 months postoperatively. Pupil size under photopic, mesopic, and scotopic conditions will be measured using the Atongmu Pupillometer. Wavefront aberrations will be measured using the OPD-Scan III Aberrometer before and after surgery. The effective optical zone (EOZ) will be measured and calculated using the Pentacam three-dimensional anterior segment analysis system. The QoV questionnaire will be administered postoperatively. Data will be collated and analyzed using statistical methods.

Study Type

Interventional

Enrollment (Estimated)

300

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Myopic or myopic astigmatism patients aged 18 to 45 years.
  • Transparent ocular media, absence of ocular diseases such as corneal leucoma, cataract, etc.
  • Round pupils with normal light reflex, absence of dyscoria, corectopia, significant persistent pupillary membrane, or absence of the pupil.
  • Absence of severe psychological or psychiatric disorders, ability to cooperate with examinations and questionnaire completion.
  • Subject agrees to participate in this clinical study and cooperate with examinations and related procedures.

Exclusion Criteria:

  • Opacities of the ocular media, such as corneal leucoma, cataract, etc.
  • Pupil deformation, displacement, significant persistent pupillary membrane, or absence of the pupil.
  • Severe psychological or psychiatric disorders.
  • Concurrent diagnosis of other ocular diseases (e.g., glaucoma, corneal opacity, uveitis, etc.).
  • History of ocular surgery or trauma.
  • Nystagmus or inability to cooperate.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Corneal refractive surgery
Corneal refractive surgery aims to correct refractive errors by altering the shape of the anterior surface of the cornea or by changing its refractive properties.
Procedure: Corneal Refractive Surgery
Corneal refractive surgery aims to correct refractive errors by altering the shape of the anterior surface of the cornea or by changing its refractive properties.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total Higher-Order Aberrations (HOAs)
Time Frame: 3 months

Root mean square (RMS) of total higher-order aberrations measured using the OPD-Scan III.

Units: micrometres (µm)
3 months
Effective Optical Zone Diameter
Time Frame: 3 months
Effective optical zone diameter measured using the Pentacam system. Units: millimetres (mm)
3 months
Central Corneal Thickness
Time Frame: 3 months
Central corneal thickness measured using the Pentacam system. Units: micrometres (µm)
3 months
Coma Aberration (RMS)
Time Frame: 3 months
Coma aberration (root mean square) measured using the OPD-Scan III. Units: micrometres (µm)
3 months
Trefoil Aberration (RMS)
Time Frame: 3 months
Trefoil aberration (root mean square) measured using the OPD-Scan III. Units: micrometres (µm)
3 months
Spherical Aberration (Zernike Z₄⁰, RMS)
Time Frame: 3 months

Spherical aberration expressed as Zernike coefficient Z₄⁰ (RMS), measured using the OPD-Scan III.

Units: micrometres (µm)
3 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Tianjin Eye Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

March 18, 2026

Primary Completion (Estimated)

September 1, 2026

Study Completion (Estimated)

September 1, 2026

Study Registration Dates

First Submitted

December 12, 2025

First Submitted That Met QC Criteria

April 4, 2026

First Posted (Actual)

April 8, 2026

Study Record Updates

Last Update Posted (Actual)

April 8, 2026

Last Update Submitted That Met QC Criteria

April 4, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • KY-2025032

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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