Development of a Validated Chart for Intermediate Vision Assessment

Democritus University of Thrace

Status: Unknown

Conditions: Myopia; Astigmatism; Presbyopia; Hyperopia

Treatments: Other: Intermediate Visual acuity (IVA) assessment

Study type: Observational

Funder types: Other

Identifiers

NCT02279446

263/13-10-2014

Details and patient eligibility

About

Development of a validated computer-based instrument (software program) for the assessment of intermediate visual acuity.

Full 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.

Enrollment: 400 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

400 participants in 4 patient groups

20/20ND group

Description:

This group will have 20/20 visual acuity both in distant and near.

Treatment:

Other: Intermediate Visual acuity (IVA) assessment

20/20D group

Description:

This group will have 20/20 distant visual acuity and variable near visual acuity.

Treatment:

Other: Intermediate Visual acuity (IVA) assessment

20/20N group

Description:

This group will have 20/20 near visual acuity and variable distant visual acuity.

Treatment:

Other: Intermediate Visual acuity (IVA) assessment

s20/20ND group

Description:

This group will have variable near and distant visual acuity (both less than 20/20)

Treatment:

Other: Intermediate Visual acuity (IVA) assessment