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

Table 5

Corneal topography parameters during follow-up.

	Preoperative	1 month	3 months	6 months	12 months	24 months
(D)
Mean±SD	54.90 ± 4.81	53.30 ± 5.25	52.54 ± 5.58	51.98 ± 5.00	52.55 ± 5.30	52.42 ± 5.37
Min/Max	47.34/64.71	45.89/63.01	40.19/68.66	40.19/62.95	43.64/63.20	43.64/63.05
p (preoperative)	-	0.202	0.011	<0.001	<0.001	<0.001
p (previous)	-	-	0.71	0.243	0.512	0.124
K1 (D)
Mean±SD	45.50 ± 2.84	43.53 ± 3.79	43.31 ± 2.25	43.32 ± 2.25	43.81 ± 2.97	43.77 ± 2.94
Min/Max	40.57/55.60	34.00/49.49	38.88/47.07	38.88/47.07	40.19/53.25	40.07/53.25
p (preoperative)	-	0.006	<0.001	<0.001	<0.001	<0.001
p (previous)	-	-	0.253	0.820	0.733	0.096
K2 (D)
Mean±SD	48.72 ± 3.08	47.20 ± 3.55	46.79 ± 3.01	46.81 ± 3.00	47.28 ± 3.51	47.25 ± 3.48
Min/Max	43.83/58.57	42.25/55.37	40.99/51.96	40.99/51.96	42.03/58.31	41.85/58.31
p (preoperative)	-	0.025	<0.001	<0.001	<0.001	<0.001
p (previous)	-	-	0.409	0.188	0.300	0.503
MPP (D)
Mean±SD	45.98 ± 2.87	44.32 ± 3.49	44.27 ± 3.55	44.24 ± 3.47	44.19 ± 2.96	44.15 ± 2.86
Min/Max	41.52/53.72	37.63/52.47	38.04/58.00	38.04/58.00	39.87/51.82	39.87/51.82
p (preoperative)	-	0.013	0.018	0.016	<0.001	<0.001
p (previous)	-	-	0.319	0.620	0.388	0.519
KVB (m)
Mean±SD	66.72±31.94	62.75±27.37	74.68±34.52	73.68±34.74	78.56±32.55	78.45±32.03
Min/Max	11/139	16/110	12/183	12/183	32/151	32/151
p (preoperative)	-	0.882	0.003	0.004	<0.001	<0.001
p (previous)	-	-	0.112	0.387	0.670	0.823

SD: standard deviation; min: minimum; max: maximum; : steepest keratometry; K₁: flat keratometry; K2: steep keratometry; MPP: mean pupillary power (4.5 mm diameter); KVB: keratoconus vertex back (posterior elevation).
: compared to preoperative visit.
: compared to previous visit.