Simultaneous Transepithelial Topography-Guided Photorefractive Keratectomy and Accelerated Cross-Linking in Keratoconus: 2-Year Follow-Up

Table 2

Preoperative patient characteristics.

	Median	Minimum	Maximum
UDVA (logMAR)	0.70	0.15	1.30
CDVA (logMAR)	0.40	0.00	1.00
SPH (D)	-1.62	-8.00	1.50
CYL (D)	-2.50	-5.00	0.00
MRSE (D)	-3.31	-12.63	0.25
	Mean ± SD	Minimum	Maximum
PACHYMETRY (μm)	470.02 ± 31.55	406	529
(D)	54.90 ± 4.81	47.34	64.71
K1 (D)	45.50 ± 2.84	40.57	55.60
K2 (D)	48.72 ± 3.08	43.83	58.57
MPP (D)	45.98 ± 2.87	41.52	53.72
KVB (μm)	66.72 ± 31.94	11	139
HOA-RMS (4 mm) (μm)	1.04 ± 0.57	0.15	2.58
COMA-RMS (4 mm) (μm)	0.91 ± 0.54	0.10	2.35
SA-RMS (4 mm) (μm)	0.19 ± 0.16	0.01	0.71
HOA-RMS (6 mm) (μm)	2.52 ± 1.25	0.43	5.83
COMA-RMS (6 mm) (μm)	2.17 ± 1.21	0.29	5.50
SA-RMS (6 mm) (μm)	0.52 ± 0.51	0.03	1.90

UDVA: uncorrected distance visual acuity; CDVA: corrected distance visual acuity; SPH: sphere; CYC: cylinder; MRSE: spherical equivalent of manifest refraction; SD: standard deviation; : steepest keratometry; K₁: flat keratometry; K2: steep keratometry; MPP: mean pupillary power (4.5 mm diameter ); KVB: keratoconus vertex back (posterior elevation); HOA-RMS: root-mean-square of total higher-order aberrations; Coma-RMS: root-mean-square of coma; SA-RMS: root-mean-square of spherical aberration.