Abstract
Purpose :
AMD – A Metamorphopsia Detector® (patent pending) is the first computer–based interactive tool to measure metamorphopsias as a patient reported outcome correlating with vision related quality of life.
We investigated the test’s sensitivity and specificity with two perspectives: anatomical changes and clinically relevant findings (need for further diagnostic or operation) respectively in eyes with and without macular diseases and examined its correlation with central retinal thickness.
Methods :
Metamorphopsia Index (consisting of 3 indices representing degree, localization and area of metamorphopsias) of AMD-Test®, best corrected visual acuity (BCVA) and central retinal thickness (CRT; spectral domain optical coherence tomography) were measured in 375 eyes of 375 patients. In monocular disease the eye with pathological findings was included. In binocular normal or pathological findings a randomized protocol selected the eye to be included. Diagnoses were classified based on a diversified Beckman classification leading to 21 diagnosis groups. Prior to the study all patients signed informed consent.
Results :
Sensitivity of AMD-Test® for clinically relevant macular findings was 94.07%, specificity was 96.89%. Sensitivity for OCT-confirmed anatomical findings was 54.59%, specificity was 95.83%. Correlation of metamorphopsia sum index with central retinal thickness was best in age-related macular degeneration with edema (Spearman’s rho 0.85) and diabetic macular edema (Spearman’s rho 0.91).
Conclusions :
By delivering variable data, AMD-Test® as an easy to use, cheap clinical or home based device reflects a patient reported outcome with high clinical sensitivity and specificity. The gap between clinical and anatomical detection rate can be explained by high false positive rate of OCT findings regarding clinical relevance (22% AREDS 1; 27% VMA) and by perceptual completion (29% AREDS 3).
AMD-Test®-detection rate of 65% in AREDS 3 emphasizes mandatory close-meshed (OCT-) controls in intermediate AMD. Relevance of CRT for metamorphopsias, bias and confounders are discussed. As it does not need interpretation AMD-Test® has the potential – especially when implemented in multimodal diagnostic and case management systems - to improve self efficiency, diagnostic and therapeutic compliance, adherence, effectiveness and quality in the monitoring and treatment of macular diseases.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.