Astigmatism, Hyperopia, Myopia, Presbyopia
Conditions
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.
Interventions
OTHERIntermediate Visual acuity (IVA) assessment
Intermediate visual acuity (IVA) will be assessed with the Intermediate Visual acuity chart which 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
Sponsors
Democritus University of Thrace
Study design
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* native Greek participants or foreigners with perfect knowledge (verbal and written) of Greek language
Exclusion criteria
* 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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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) |
Countries
Greece
Contacts
Primary ContactGeorgios Labiris, MD, PhD
Outcome results
None listed