Table 1. Normal values of anterior ocular parameters.

	M±SD	Minimum	Maximum
CCT (µm)	552±26	483	621
ACD (mm)	3.03±0.35	1.89	3.83
KPI (%)	2.8±4.5	0	21.9
PD (mm)	3.04±0.56	1.24	4.87
SimK Values (D)
SimK average	43.47±1.29	39.43	47.17
SimK f	42.96±1.28	39.20	46.54
SimK s	43.99±1.38	39.66	47.81
Astigmatism	1.03±0.61	0.07	3.16
Anterior Instantaneous Curvature (D)
K average	43.23±1.29	39.23	46.63
K f	42.74±1.28	39.09	46.00
Ks	43.72±1.37	39.36	47.26
Astigmatism	0.98±0.55	0.1	2.94
ε2	0.25±0.17	−1.06	0.61
Posterior Axial Curvature (D)
K average	−6.27±0.23	−6.84	−5.67
K f	−6.10±0.22	−6.66	−5.50
Ks	−6.44±0.26	−7.02	−5.73
astigmatism	−0.34±0.14	−0.71	−0.02
ε2	0.31±0.38	−0.24	3.35
Total Corneal Power (D)
Mean	41.77±1.27	37.81	45.44
Flat	41.31±1.26	37.51	44.90
Steep	42.24±1.34	38.10	45.98
Astigmatism	0.93±0.58	0.06	3.10
Central Avg. (0–4 mm diameter)	41.73±1.27	37.78	45.45
Paracentral Avg. (4–7 mm diameter)	42.25±1.34	38.33	45.85
Peripheral Avg. (7–8 mm diameter)	42.63±1.46	38.85	46.52
Axial Curvature (D)
Central Avg. (0–4 mm diameter)	43.50±1.30	39.48	47.25
Paracentral Avg. (4–7 mm diameter)	42.98±1.28	39.05	46.28
Peripheral Avg. (7–8 mm diameter)	42.33±1.27	38.81	45.38
RMS Wavefront (µm)
Total	1.33±0.87	0.37	7.95
HOA	0.61±0.33	0.18	3.17
Spherical Aberration	0.19±0.13	−0.45	0.80

Note: anterior chamber depth (ACD), average (Avg.), central corneal thickness (CCT), diopter (D), flat (f), high-order aberration (HOA), keratoconus prediction index (KPI), mean (M), pupil diameter (PD), root mean square (RMS), simulated keratometry (SimK), steep (s), standard deviation (SD),