Table 3. Mean values of GDx ECC retinal nerve fiber layer parameters in glaucoma and control eyes with areas under the receiver operating characteristic curves and sensitivities at fixed specificities.
| Retinal nerve fiber layer parameters (in microns) | Control (mean±SD) | Glaucoma (mean±SD) | P-value | AUC | Sensitivity at 95% specificity | Sensitivity at 80% specificity |
|---|---|---|---|---|---|---|
| Quality scorea | 9 (9, 9) | 9 (9, 9) | 0.69 | |||
| Typical scan scorea | 100 (100, 100) | 100 (100, 100) | 0.08 | |||
| Residual retardationa | 1 (0, 2) | 1 (0, 2) | 0.86 | |||
| Temporal quadrant | 19.8±6.6 | 18.9±7.2 | 0.36 | 0.555 (0.466–0.638) | 12.3% (4.3–21.1) | 29.2% (15.1–42.0) |
| Superior quadrant | 55.8±10.1 | 41.3±13.1 | <0.001 | 0.796 (0.724–0.859) | 47.2% (25.5–61.5) | 67.0% (53.9–78.2) |
| Nasal quadrant | 33.9±7.8 | 27.5±8.6 | <0.001 | 0.730 (0.645–0.808) | 25.5% (12.6–41.1) | 46.2% (27.9–58.4) |
| Inferior quadrant | 57.2±9.7 | 40.9±11.4 | <0.001 | 0.850 (0.793–0.903) | 57.5% (36.7–73.4) | 75.5% (65.9–85.0) |
| Average | 46.9±6.6 | 35.3±8.4 | <0.001 | 0.855 (0.789–0.903) | 48.1% (33.7–62.7) | 78.3% (67.0–88.5) |
| Average SD | 21.7±5.6 | 15.6±5.8 | <0.001 | 0.751 (0.675–0.814) | 29.2% (16.8–41.2) | 54.7% (39.2–70.4) |
| NFI | 27 (19, 42) | 80 (55, 98) | <0.001 | 0.876 (0.813–0.920) | 59.4% (30.9–72.1) | 80.2% (67.5–89.2) |
Abbreviations: AUC, area under the receiver operating characteristic curve; CI, confidence interval; ECC, enhanced corneal compensation; NFI, nerve fiber indicator; SD, standard deviation.
a
Median with inter-quartile range. AUCs and sensitivities are adjusted for the difference in disc area between the control and glaucoma group.