Development of a Validated Chart for Intermediate Vision Assessment
- Conditions
- HyperopiaPresbyopiaMyopiaAstigmatism
- Interventions
- Other: Intermediate Visual acuity (IVA) assessment
- Registration Number
- NCT02279446
- Lead Sponsor
- Democritus University of Thrace
- Brief Summary
Development of a validated computer-based instrument (software program) for the assessment of intermediate visual acuity.
- Detailed Description
Development of a validated computer-based instrument (software program) for the assessment of intermediate visual acuity (IVA). It is known that no validated method for the evaluation of IVA exists.
Primary objective of the study is to validate a specific computer-based chart (optotype) that will enable: a) comparative studies among different groups of presbyopic patients with refractive errors (ie. myopia, hyperopia, and/or astigmatism), and, b) assessment of the efficacy of surgical refractive procedures (ie. LASIK) on presbyopic patients.
Intermediate Visual acuity chart is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5
Validation of the computer-based IVA chart will be done by correlating the results of the IVA chart to the corresponding ones from the validated 20/20 distant and Jaeger near visual acuity charts, in a random sample of study participants with different refractive errors and different near and distant visual acuities.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 400
- native Greek participants or foreigners with perfect knowledge (verbal and written) of Greek language
- glaucoma or suspicion for glaucoma,
- corneal disease or suspicion for corneal disease
- fundus disease or suspicion for fundus disease
- pregnancy or nursing,
- underlying autoimmune disease
- mental or neurologic disease
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description 20/20N group Intermediate Visual acuity (IVA) assessment This group will have 20/20 near visual acuity and variable distant visual acuity. 20/20ND group Intermediate Visual acuity (IVA) assessment This group will have 20/20 visual acuity both in distant and near. 20/20D group Intermediate Visual acuity (IVA) assessment This group will have 20/20 distant visual acuity and variable near visual acuity. s20/20ND group Intermediate Visual acuity (IVA) assessment This group will have variable near and distant visual acuity (both less than 20/20)
- Primary Outcome Measures
Name Time Method Intermediate Visual Acuity (IVA) 6 months Number of participants that their intermediate visual acuity measured with the "intermediate visual acuity chart" will be statistically correlated with distant visual acuity (measured by 20/20 chart) and near visual acuity (measured by Jaeger chart)
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
Eye Institute Of thrace
🇬🇷Alexandroupolis, Evros, Greece