Impact of Positive & Negative Lens-Induced Defocus on Contrast-Sensitivity in Myopic & Non-Myopic Adults

NCT06753032 | Active Not Recruiting DMC

• 1 other identifier: MSRSW/Batch-Fall22/750
• Study Type: interventional
• Target: 36
• Locations: 1 country
• Sites: 1

Brief Summary

examines the influence of lens-induced defocus on contrast sensitivity-a crucial aspect of visual performance.Each participant experiences both positive and negative defocus through different lenses, with measurements taken for contrast sensitivity using the Pelli-Robson chart. Outcomes are evaluated at baseline, 2 weeks, and 4 weeks to understand the effect of defocus over time.

Conditions

Myopia

Outcome Measures

Primary Outcomes (2)

• Contrast Sensitivity

  Measured with the Pelli-Robson Contrast Sensitivity Chart, capturing changes in participants' ability to detect low-contrast visual stimuli under defocus conditions.

  12 Months

• Visual Fatigue

  Evaluated with the Visual Fatigue Questionnaire (VFQ) and Computer Vision Syndrome assessing symptoms like eye strain, discomfort, and fatigue following lens-induced defocus.

  12 months

Study Arms (4)

interventional group

EXPERIMENTAL

Diagnostic Test: Positive Lens-Induced Defocus Using Spectacle Lenses (+2.00 D) for Myopic Participants

Interventional group II

EXPERIMENTAL

Diagnostic Test: Negative Lens-Induced Defocus Using Spectacle Lenses (-2.00 D) for Myopic Participants

Interventional group III

ACTIVE COMPARATOR

Combination Product: Positive Lens-Induced Defocus Using Spectacle Lenses (+2.00 D) for Non-Myopic Participants

Interventional group IV

ACTIVE COMPARATOR

Combination Product: Negative Lens-Induced Defocus Using Spectacle Lenses (-2.00 D) for Non-Myopic Participants

Interventions

Positive Lens-Induced Defocus Using Spectacle Lenses (+2.00 D) for Myopic Participants DIAGNOSTIC_TEST

Intervention Description: This group will be exposed to positive defocus induced by +2.00 D spectacle lenses. The lenses are designed to create optical blur to evaluate the effects on contrast sensitivity and visual fatigue. Measurements will be conducted at baseline, 2 weeks, and 4 weeks after exposure to assess changes in visual function."

interventional group

Negative Lens-Induced Defocus Using Spectacle Lenses (-2.00 D) for Myopic Participants DIAGNOSTIC_TEST

Intervention Description: This group will be exposed to negative defocus induced by -2.00 D spectacle lenses. The induced defocus will allow for the evaluation of its impact on contrast sensitivity and visual fatigue. Assessments will be carried out at baseline, 2 weeks, and 4 weeks."

Interventional group II

Positive Lens-Induced Defocus Using Spectacle Lenses (+2.00 D) for Non-Myopic Participants COMBINATION_PRODUCT

ntervention Description: This group will undergo positive defocus using +2.00 D spectacle lenses. The intervention aims to examine the effect of induced defocus on contrast sensitivity and visual fatigue in non-myopic participants. Data will be collected at baseline, 2 weeks, and 4 weeks."

Interventional group III

Negative Lens-Induced Defocus Using Spectacle Lenses (-2.00 D) for Non-Myopic Participants COMBINATION_PRODUCT

Intervention Description: This group will experience negative defocus induced by -2.00 D spectacle lenses. The purpose is to evaluate how negative lens-induced defocus affects contrast sensitivity and visual fatigue in non-myopic participants. Measurements will be taken at baseline, 2 weeks, and 4 weeks.

Interventional group IV

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Adults aged 18 to 50 years.
• Participants with a confirmed diagnosis of myopia or non-myopia.
• Best corrected visual acuity of 20/30 or better.
• No history of ocular surgery or significant ocular disease.
• Informed consent was obtained.

You may not qualify if:

• Individuals with a history of systemic diseases affecting vision (e.g., diabetes, hypertension).
• Presence of binocular vision anomalies or strabismus.
• Pregnant or nursing women.
• Any current use of medications affecting visual function (e.g., medications causing visual side effects).

Sponsors & Collaborators

• Superior University: lead

Study Sites (1)

Tehsil Headquarters (THQ)

Taunsa, Punjab Province, Pakistan

Location

MeSH Terms

Conditions

Myopia

Condition Hierarchy (Ancestors)

Refractive Errors; Eye Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: December 13, 2024
• First Posted: December 31, 2024
• Study Start: February 28, 2024
• Primary Completion: July 31, 2024
• Study Completion: March 1, 2025
• Last Updated: December 31, 2024

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will not share

Locations

PA (1)