Table 2.
Dark-Adapted Chromatic Perimetry Values by Distance from Fixation and Age-Related Macular Degeneration Status
| Median (Interquartile Range) | ||||
|---|---|---|---|---|
| Characteristic | Total (N = 51) | AMD (n = 20) | Control (n = 31) | P Valuea |
| Cyan threshold (505 nm), dB | ||||
| All pointsb | 52.0 (48.0, 56.0) | 50.0 (48.0, 52.0) | 52.0 (48.0, 56.0) | 0.005 |
| 4° | 48.0 (46.0, 52.0) | 48.0 (44.0, 48.0) | 49.0 (48.0, 52.0) | 0.002 |
| 5.657° | 52.0 (48.0, 56.0) | 50.0 (48.0, 52.0) | 54.0 (50.0, 56.0) | <0.001 |
| 8° | 54.0 (50.0, 56.0) | 52.0 (50.0, 56.0) | 54.0 (50.0, 56.0) | 0.158 |
| Red threshold (625 nm), dB | ||||
| All pointsb | 30.0 (28.0, 34.0) | 30.0 (28.0, 32.0) | 32.0 (30.0, 34.0) | 0.003 |
| 4° | 30.0 (26.0, 30.0) | 28.0 (26.0, 30.0) | 30.0 (28.0, 32.0) | 0.003 |
| 5.657° | 30.0 (28.0, 34.0) | 30.0 (28.0, 30.0) | 32.0 (30.0, 34.0) | 0.002 |
| 8° | 32.0 (30.0, 34.0) | 30.0 (30.0, 32.0) | 34.0 (30.0, 34.0) | 0.005 |
| Sensitivity difference, dB | ||||
| All pointsb | 20.0 (18.0, 24.0) | 20.0 (18.0, 22.0) | 22.0 (18.0, 24.0) | 0.204 |
| 4° | 20.0 (18.0, 22.0) | 20.0 (18.0, 22.0) | 20.0 (18.0, 22.0) | 0.381 |
| 5.657° | 22.0 (20.0, 24.0) | 20.0 (18.0, 22.0) | 22.0 (20.0, 24.0) | 0.019 |
| 8° | 22.0 (20.0, 24.0) | 22.0 (20.0, 24.0) | 22.0 (18.0, 24.0) | 0.771 |
| Rod intercept time, min | ||||
| All points* | 7.2 (5.9, 9.8) | 9.9 (7.6, 12.8) | 6.5 (5.4, 7.9) | <0.001 |
| 4° | 7.0 (5.7, 9.8) | 10.0 (7.8, 14.0) | 6.3 (5.3, 7.8) | <0.001 |
| 5.657° | 7.2 (5.8, 9.9) | 9.9 (7.7, 12.7) | 6.3 (5.5, 7.6) | <0.001 |
| 8° | 7.4 (6.0, 9.8) | 9.5 (7.5, 12.3) | 6.7 (5.5, 8.0) | <0.001 |
n = number of participants, with multiple test points within each ring for each participant (528 test loci total).
a
P values comparing AMD to control participants estimated using Somers’ D statistic accounting for within-participant correlation.
b
Threshold values and rod intercept time values taken from all visual field loci within 8° from fixation for a single eye per participant.