Abstract
Purpose :
Comparative analysis of examination results from 3D Computer-automated Threshold Amsler Grid test (3D-CTAG; Fink & Sadun, JBO 2004) and microperimetry in wet AMD patients.
Methods :
Group #1: Wet AMD patients (n=35, 43 eyes). Group #2 (Control): Healthy patients (n=25, 50 eyes). All patients underwent 3D-CTAG testing and microperimetry. 3D-CTAG: Subjects in a dark room were placed on a chin-head-rest in front of an iPad III wearing optical corrections for presbyopia. Indices for 3D-CTAG analysis: Number of scotomas per eye (ND), lowest perceivable contrast level (CL), absolute hill-of-vision volume lost (AVL), and relative volume lost (VLRH). Microperimetry, MAYA, CenterVue, Italy: Tested visual field 20°×20°, 68 points. Indices for microperimetry analysis: Average threshold (AT) in dB, average threshold in choroidal neovascularization (ATCNV) in dB, and percentages of fixation points located within 1° (P1). The following non-parametric statistical methods were used: Shapiro-Wilk test, Mann-Whitney U-test, and Spearman's rank correlation coefficient.
Results :
Result format: Median(25%-quartile;75%-quartile). Group #1: ND=1(1;2), CL=17(11;25)%, AVL=4711(2932.5;6968)%deg2, and VLRH=6.8(4.24;10.06)%. AT=19.1(11.45;22.7)dB, ATCNV=15.9(7.61;18.86)dB, and P1=34(27.5;54.5)%. Group #2: ND=0(0;0), AVL=0(0;0), and VLRH=0(0;0). AT=29.1(28.8;30.8)dB and P1=95(93;99)%. A medium correlation between AT and AVL (ρ=-0.69, p=0.00001) and a strong correlation between ATCNV and AVL (ρ=-0.85, p=0.00001) were determined, i.e., the visual field depressions detected by both methods coincide. The fixation stability (P1) also has a negative correlation with AVL (ρ=-0.65, p=0.00095).
Conclusions :
Both 3D-CTAG and microperimetry demonstrate functional disorders of the macular area in wet AMD. The average threshold reduction in the CNV area correlates well with the AVL in 3D-CTAG. It seems preferable to use 3D-CTAG in patients with low visual acuity (<6/30) compared to microperimetry because of a more stable fixation. 3D-CTAG testing appears to be less tedious for patients because it takes only 4-5 min. per eye compared to 10-15 min. for microperimetry.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.