Table 5 Morphogeometric variables measured in healthy and keratoconic corneas
From: Study and characterization of morphogeometric parameters to assist diagnosis of keratoconus
Morphogeometric variables | Normal | Stage I | Stage II | Stage III–IV | p (KW test) |
|---|---|---|---|---|---|
Mean ± SD (range) | Mean ± SD (range) | Mean ± SD (range) | Mean ± SD (range) | ||
Total corneal volume (mm3) | 25.90 ± 0.31 (25.59 to 26.21) | 23.51 ± 0.48 (23.03 to 23.99) | 23.09 ± 0.59 (22.5 to 23.68) | 20.01 ± 2.88 (17.13 to 22.89) | 0.0001 |
(ES) | – | 1.21 | 1.39 | 3.41 | |
Anterior corneal surface area (mm2) | 43.13 ± 0.06 (43.07 to 43.19) | 43.42 ± 0.13 (43.29 to 43.55) | 43.50 ± 0.17 (43.33 to 43.67) | 44.31 ± 0.21 (44.1 to 44.52) | 0.0001 |
(ES) | – | − 1.16 | − 1.66 | − 4.79 | |
Posterior corneal surface area (mm2) | 44.31 ± 0.09 (44.22 to 44.40) | 44.81 ± 0.21 (44.6 to 45.02) | 44.99 ± 0.22 (44.7 to 45.21) | 45.39 ± 0.32 (45.07 to 45.71) | 0.0001 |
(ES) | – | − 0.101 | − 1.49 | − 4.21 | |
Total corneal surface area (mm2) | 104.02 ± 0.29 (103.73 to 104.31) | 103.68 ± 0.43 (103.25 to 104.11) | 103.59 ± 0.39 (103.2 to 103.98) | 103.53 ± 0.52 (103.01 to 104.05) | 0.0001 |
(ES) | – | 0.31 | 0.20 | 0.29 | |
Anterior apex deviation (mm) | 0.0001 ± 0.00001 (0.0000 to 0.0002) | 0.006 ± 0.0021 (0.0039 to 0.0081) | 0.009 ± 0.0035 (0.0055 to 0.0125) | 0.012 ± 0.004 (0.008 to 0.016) | 0.0001 |
(ES) | – | − 1.11 | − 1.39 | − 5.70 | |
Posterior apex deviation (mm) | 0.0771 ± 0.0128 (0.0643 to 0.0899) | 0.17 ± 0.029 (0.141 to 0.199) | 0.201 ± 0.03 (0.171 to 0.231) | 0.237 ± 0.051 (0.186 to 0.288) | 0.0001 |
(ES) | – | − 1.19 | − 1.40 | − 1.23 | |
Anterior minimum thickness point deviation (mm) | 0.901 ± 0.58 (0.429 to 2.201) | 0.99 ± 0.21 (0.052 to 0.210) | 1.066 ± 0.25 (0.533 to 3.22) | 0.299 ± 0.3 (0.244 to 0.568) | 0.0001 |
(ES) | – | − 0.69 | − 0.77 | 1.88 | |
Posterior minimum thickness point deviation (mm) | 0.780 ± 0.013 (0.38 to 2.11) | 0.961 ± 0.033 (0.541 to 1.89) | 0.989 ± 0.04 (0.450 to 2.899) | 0.360 ± 0.047 (0.188 to 0.529) | 0.0001 |
(ES) | – | − 0.7 | − 0.73 | 1.70 |