Abstract
Purpose:
Patients with age-related macular degeneration (AMD) need to undergo regular testing of their visual acuity. A tool for self-measurement to be run on an iPad was developed to enable patients to have regular testing by themselves. It is available in German, English, Spanish and Japanese. This project was designed to evaluate whether iPad-based vision auto-testing is a feasible method for patients with AMD compared to established instruments.
Methods:
The project was run in 4 ophthalmologist’s offices. Target sample size was 100 patients; only patients with an initial vision of at least 0.05 were included. Patients had to consent to a threepart vision test every 4 weeks for 6 months. Visual acuity was measured by a) distance vision testing by projection of Landolt rings (EN ISO 8596) b) near vision test charts (Oculus) with Landolt rings and c) auto-measurement with Landolt rings using the iPad App “Eyetest - Control your visual acuity”. Patients were initially advised how to use the iPad App. All tests were performed in the office. Test results were defined to be consistent when they differed to a maximum of one line.
Results:
112 patients of 57 to 92 years of age (mean 77.2 yrs) were included. Nearly all patients had never used an iPad before (96% vs. 4%). Results for vision tests by projection and iPad were consistent in 76% (right eye) and 83% (left eye) of the measurements. Near vision test charts were used as a control. Results acquired by near vision test charts frequently differed from projection results by 2 or more lines. At the end of study, patients were asked for their preference. The majority of patients (81.25%) chose the iPad App as their preferred method to test visual acuity, only 12.5% chose the projection method, 6.25% preferred near distance test charts.
Conclusions:
The fact that over 80% of the patients prefer the iPad App for vision testing illustrates the feasibility of the method. It is easy to use even for former iPad non-users and delivers results consistent with established vision testing instruments. This suggests that the iPad App is suitable to support patients and ophthalmologists in the routine care of AMD. Features like an adjustable reminder and a mail function contribute to its value. The Amsler grid will be included and an automated distance adjustment will be implemented to further improve feasibility and reliability of the tool. Home use of the auto-vision App will be evaluated.
Keywords: 754 visual acuity •
412 age-related macular degeneration •
585 macula/fovea