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Not yet recruiting NCT07518316

Factors Influencing Subjective Visual Quality in Human Eyes

No phase Interventional Corneal Wavefront Aberration Refractive Errors

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Corneal Refractive Surgery.
Who it may be relevant to
Registry conditions: Corneal Wavefront Aberration, Refractive Errors. Basic parameters: 18 years — 45 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Center list to be confirmed — check the primary protocol.
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

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Official title

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

Overview

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.

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.

Interventions

  • 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.

Primary outcome measures

  • Total Higher-Order Aberrations (HOAs) [Time frame: 3 months]
  • Effective Optical Zone Diameter [Time frame: 3 months]
  • Central Corneal Thickness [Time frame: 3 months]
  • Coma Aberration (RMS) [Time frame: 3 months]
  • Trefoil Aberration (RMS) [Time frame: 3 months]
  • Spherical Aberration (Zernike Z₄⁰, RMS) [Time frame: 3 months]

Eligibility criteria

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.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation
N/A
Model
Single group
Masking
Open label
Primary purpose
Prevention

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07518316 · KY-2025032

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗