Table 2.
Comparison of the mean values of the optic disc parameters between NTG and POAG patients
| Optic disc parameters | Mean ± SD
|
MD (95% CI) | T stat (df) | P-value* | |
|---|---|---|---|---|---|
| NTG (n=32) | POAG (n=45) | ||||
| Disc area, mm2 | 2.65±0.41 | 2.40±0.36 | 0.26 (0.08–0.44) | 2.84 (75) | 0.006 |
| Cup area, mm2 | 1.54±0.43 | 1.32±0.40 | 0.22 (0.02–0.40) | 2.25 (75) | 0.027 |
| Rim area, mm2 | 1.12±0.41 | 1.07±0.44 | 0.05 (−0.15–0.24) | 0.45 (75) | 0.651 |
| Cup volume, mm3 | 0.47±0.28† | 0.40±0.37† | – | −1.32‡ | 0.187¶ |
| Rim volume, mm3 | 0.23±0.13 | 0.21±0.15 | 0.02 (−0.05–0.08) | 0.50 (75) | 0.617 |
| Cup/disc area ratio | 0.58±0.14 | 0.55±0.15 | 0.03 (−0.04–0.09) | 0.72 (75) | 0.473 |
| Linear cup/disc ratio | 0.76±0.09 | 0.74±0.11 | 0.02 (−0.03–0.07) | 0.80 (75) | 0.425 |
| Mean cup depth, mm | 0.37±0.09 | 0.35±0.13 | 0.12 (−0.03–0.07) | 0.74 (75) | 0.461 |
| Maximum cup depth, mm | 0.77±0.16 | 0.75±0.23 | 0.02 (−0.07–0.12) | 0.44 (75) | 0.663 |
| Cup shape measure | −0.04±0.06 | −0.06±0.06 | 0.02 (−0.01–0.05) | −1.25 (75) | 0.123 |
| Height variation contour, mm | 0.39±0.19† | 0.33±0.15† | – | −1.63‡ | 0.103¶ |
| Mean RNFL thickness, mm | 0.15±0.10 | 0.15±0.08 | 0.00 (−0.04–0.04) | 0.83 (75) | 0.934 |
| RNFL cross-sectional area, mm2 | 0.88±0.60 | 0.83±0.48 | 0.05 (−0.19–0.30) | 0.43 (75) | 0.670 |
Notes:
*
Independent t-test was applied.
†
Median (interquartile range).
‡
Z stat.
¶
Mann–Whitney test was applied. Bold text indicates that the values reached significant level.
Abbreviations: NTG, normal-tension glaucoma; POAG, primary open-angle glaucoma; SD, standard deviation; MD, mean difference; CI, confidence interval; df, degree of freedom; RNFL, retina nerve fiber layer.