Table 1.

Patient demographics

Preoperative characteristics	PRK control (n = 399)	PRK enhancements (n = 188)	P value
Age (years)
Mean ± SD	32.5 ± 7.0	34.86 ± 9.39	0.200
Range	18 to 53	19 to 55
Sex, no. (%)
Male	138 (66%)	71 (50%)	0.004
Female	72 (34%)	70 (50%)
Surgical eye, no. (%)
Right	200 (50%)	105 (56%)	0.195
Left	199 (50%)	83 (44%)
CDVA (logMAR)
Mean	0.00	0.00	0.557
Sphere (D)
Mean ± SD	− 3.21 ± 1.81	− 3.69 ± 2.27	0.013
Range	− 8.75 to + 1.25	− 8.75 to + 2.25
Cylinder (D)
Mean ± SD	− 0.92 ± 0.92	− 1.09 ± 1.02	0.058
Range	− 6.00 to 0.00	− 6.75 to 0.00
Spherical equivalent (D)
Mean ± SD	− 3.67 ± 1.79	− 4.23 ± 2.33	0.004
Range	− 8.88 to 0.00	− 12.13 to + 2.25
Pachymetry (μm)
Mean ± SD	519.92 ± 33.76	522.28 ± 31.08	0.701
Range	462 to 588	468 to 594
K1 values (D)
Mean ± SD	43.16 ± 1.59	43.60 ± 1.63	0.153
Range	40.40 to 46.40	38.90 to 48.70
K2 values (D)
Mean ± SD	44.59 ± 1.69	44.90 ± 2.69	0.319
Range	41.30 to 47.20	39.90 to 72.90

SD standard deviation, UDVA uncorrected distance visual acuity, CDVA corrected distance visual acuity, D diopter