Abstract
Purpose :
The card version of D-Charts are effective at mapping changes in metamorphopsia pre- and post-surgery within the central visual field in patients with macular disease. Recently a software version of the D-Charts has been developed to reduce recording time. Here we measure metamorphopsia and central field loss using the software version of the D-Chart and compare the results with the Amsler chart. Furthermore we use the D-Charts to monitor changes in the central visual field that occur during anti-VEGF treatment.
Methods :
The D-Charts use octagonal grids, divided into eight sectors, formed by black elements (squares) of various densities. The grids are at varying eccentricities between 0.5 and 12 degrees from fixation. Subjects fixate the centre of the D-charts and touch the screen in the distorted sector. The metamorphopsia score (the maximal element separation which produced distortion or field loss) is determined for each ring and sector. The results provide two dimensional maps of metamorphopsia severity and visual loss. Twenty fully corrected subjects with macular disease were tested using the software version of the D-Chart and the Amsler chart. In the second part of the study a further seven subjects were measured during a period of anti-VEGF treatment to examine changes in central field occurring during treatment.
Results :
The total metamorphopsia score (MTotal) did not correlate with the area of distortion reported on the Amsler chart although the size and location of the field plots using the two charts were similar. The D-Chart provided greater detail relating to the distribution of distortion and field loss and recording was completed in less than 2 minutes per eye. In the second part of the study the D-Chart plots changed in line with the predicted effects of anti-VEGF treatment.
Conclusions :
The increased information provided by the D-Chart makes comparison with Amsler chart results difficult although the size and location of the field plots were consistent. The software version of the D-Chart is easy to use and maps changes in metamorphopsia and central field loss that occur in patients with macular disease.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.