Table 2.
The means of Corvis parameters in two study groups and the results of their comparison.
| Variable | Normal group |
Keratoconus group |
P Value |
|---|---|---|---|
| Mean ± SD | Mean ± SD | ||
| A1T (ms) | 7.6 ± 0.51 | 6.72 ± 0.28 | <0.0001 |
| A1V (m/s) | 0.12 ± 0.03 | 0.14 ± 0.03 | <0.0006 |
| A2T (ms) | 20.88 ± 0.41 | 21.51 ± 0.33 | <0.0001 |
| A2V (m/s) | −0.31 ± 0.08 | −0.42 ± 0.08 | <0.0001 |
| HCDA (mm) | 0.88 ± 0.10 | 1.11 ± 0.15 | <0.0001 |
| HCR (mm) | 7.66 ± 0.68 |
5.72 ± 0.1 |
<0.0001 |
| Median |
Median |
||
| A1L (mm) | 1.78 | 1.68 | 0.0028 |
| A2L (mm) | 1.83 | 1.75 | 0.32 |
| HCPD (mm) | 4.49 | 4.82 | 0.0003 |
| HCT (ms) | 16.17 | 16.35 | 0.13 |
SD: Standard deviation; A1T: First applanation time; A1V: First applanation velocity; A2T: Second applanation time; A2V: Second applanation velocity; HCDA: Highest concavity deformation amplitude; HCR: Highest concavity radius; A1L: First applanation length; A2L: Second applanation length; HCPD: Highest concavity peak distance; HCT: Highest concavity time.