Table 1.
Demographics and characteristics of study population.
| Training dataset* | Internal test dataset | External test dataset | |
|---|---|---|---|
| Sreening subjects | 91,367 | 1,556 | 51,447 |
| Recruit subjects | 1,518 | 457 | 638 |
| Diagnosis | |||
| Normal (%)† | 999 (65.81) | 383 (83.81) | 527 (82.60) |
| Subclinical keratoconus (%) | 69 (4.55) | 38 (8.32) | 43 (6.74) |
| Clinical keratoconus‡ (%) | 450 (29.64) | 36 (7.88) | 68 (13.66) |
| Recommend corneal | 519 (34.19) | 74 (16.19) | 111 (17.40) |
| topography (%) | |||
| Demographics | |||
| Age, years (mean ± SD) | 34.43 ± 12.04 | 26.54 ± 8.58 | 28.26 ± 12.52 |
| Sex | |||
| Female (%) | 789 (51.98) | 236 (51.64) | 330 (51.72) |
| Male (%) | 729 (48.02) | 221 (48.36) | 308 (48.28) |
| Subjective visual impairment | |||
| Right (%) | 482 (31.75) | 27 (5.91) | 68 (10.61) |
| Left (%) | 503 (33.14) | 22 (4.81) | 67 (10.50) |
| Basic examinations | |||
| BCVA, logMAR | |||
| Right (mean ± SD) | 0.265 ± 0.431 | 0.056 ± 0.199 | 0.092 ± 0.256 |
| Left (mean ± SD) | 0.243 ± 0.379 | 0.053 ± 0.183 | 0.085 ± 0.258 |
| IOP, mmHg | |||
| Right (mean ± SD) | 12.12 ± 4.52 | 15.78 ± 3.24 | 14.90 ± 3.89 |
| Center (mean ± SD) | 11.98 ± 3.67 | 15.89 ± 3.23 | 14.92 ± 3.76 |
| Autokeratometry | |||
| Refrective errors | |||
| Sphere, diopter | |||
| Right | −3.78 ± 3.76 | −2.51 ± 3.07 | −2.60 ± 3.04 |
| Left | −3.84 ± 3.85 | −2.36 ± 3.00 | −2.35 ± 3.44 |
| Cylinder, diopter | |||
| Right | −2.94 ± 2.30 | −1.43 ± 1.57 | −1.81 ± 1.91 |
| Center | −3.14 ± 2.78 | −1.49 ± 1.60 | −1.91 ± 1.73 |
| Cylinderic axis, degree | |||
| Right | 87.99 ± 68.30 | 97.10 ± 71.63 | 91.02 ± 72.14 |
| Left | 114.56 ± 63.25 | 102.93 ± 67.44 | 109.80 ± 66.22 |
| Corneal power | |||
| K1 (flatter), diopter | |||
| Right | 43.70 ± 4.40 | 42.59 ± 2.11 | 43.30 ± 2.59 |
| Left | 43.27 ± 6.53 | 42.54 ± 1.94 | 43.30 ± 2.67 |
| K2 (steeper), diopter | |||
| Righht | 46.76 ± 5.72 | 44.25 ± 2.98 | 44.99 ± 4.60 |
| Left | 46.74 ± 5.79 | 44.18 ± 2.71 | 45.32 ± 3.67 |
| K2 axis, degree | |||
| Right | 97.226 ± 32.19 | 86.05 ± 26.52 | 89.25 ± 21.41 |
| Left | 81.02 ± 33.00 | 91.31 ± 25.81 | 88.57 ± 25.01 |
| Corneal topography | |||
| Abnormal in tangenital map§ | |||
| Right (%) | 513 (33.79) | 73 (15.97) | 116 (18.18) |
| Left (%) | 496 (32.67) | 73 (15.97) | 116 (18.18) |
| D-score in BAD | |||
| Right (mean ± SD) | 2.14 ± 0.67 | 1.65 ± 0.33 | 1.80 ± 0.41 |
| Pathologic (%) | 431 (28.39) | 35 (7.66) | 81 (12.70) |
| Left (mean±SD) | 2.13 ± 0.67 | 1.65 ± 0.33 | 1.80 ± 0.41 |
| Pathologic (%) | 421 (27.73) | 30 (6.56) | 83 (13.01) |
BCVA, best-corrected visual acuity; BAD, Belin/Ambrósio enhanced ectasia display; SD, standard deviation.
*
Down sampling method was adjusted for normal subjects.
†
Normal in both eyes.
‡
Clinical keratoconus in at least one eyes.
§
Abnormal localized steepening or an asymmetric bow-tie pattern.