Journal of Ophthalmology

Research Article

Comparison of 9.0 and 9.2 mm Flap Diameter Options of Femtosecond Laser In-Situ Keratomileusis for Hypermetropia and Hypermetropic Astigmatism

Table 1

The comparison of demographic and clinical characteristics of the 9.0 (n = 34) and 9.2 (n = 34) mm diameter flap groups.


	9.0 mm diameter flap group (mean ± SD)			9.2 mm diameter flap group (mean ± SD)
	Preoperative value	Postoperative value	value	Preoperative value	Postoperative value	value	value

Spherical RE (D)	3.26 ± 1.75 (0.75 to 5.75)	0.17 ± 0.56 (−0.75 to 1.00)	<0.001	2.67 ± 1.48 (0.75 to 5.75)	0.01 ± 0.35 (−0.50 to 0.75)	<0.001	^†0.177 ^‡0.274
Cylindrical RE (D)	−2.82 ± 1.34 (−3.75 to 0.00)	−0.55 ± 0.23 (−1.00 to −0.25)	<0.001	−1.96 ± 1.60 (−3.75 to 0.00)	−0.35 ± 0.20 (−0.75 to 0.00)	<0.001	^†0.059 ^‡0.055
MRSE (D)	1.86 ± 1.81 (0.75 to 5.50)	−0.10 ± 0.53 (−1.00 to 0.63)	<0.001	1.69 ± 1.99 (0.75 to 5.00)	−0.17 ± 0.33 (−0.75 to 0.63)	<0.001	^†0.754 ^‡0.533
BCVA (log MAR)	−0.13 ± 0.12 (0.00 to −0.30)	−0.07 ± 0.09 (0.00 to −0.30)	<0.001	−0.10 ± 0.06 (0.00 to −0.30)	−0.05 ± 0.14 (0.00 to −0.30)	<0.001	^†0.306 ^‡0.422
K1 flat (D)	41.20 ± 1.84 (37.01 to 44.29)	43.47 ± 1.63 (41.10 to 47.10)	<0.001	41.08 ± 1.93 (37.29 to 45.30)	42.98 ± 2.12 (40.20 to 47.80)	<0.001	^†0.915 ^‡0.114
K2 steep (D)	44.32 ± 1.68 (40.61 to 47.87)	44.50 ± 1.68 (41.50 to 48.10)	<0.001	43.37 ± 1.99 38.18 to 46.19)	43.63 ± 1.99 (40.90 to 48.40)	<0.001	^†0.054 ^‡0.052
IOP (mmHg)	14.79 ± 4.58 (10 to 21)	13.67 ± 3.27 (10 to 21)	<0.001	15.88 ± 2.45 (10 to 21)	12.85 ± 2.20 (10 to 21)	<0.001	^†0.080 ^‡0.221
CCT (μm)	549.30 ± 32.40 (496 to 614)	502.00 ± 44.57 (422 to 599)	<0.001	548.76 ± 31.98 (503 to 628)	522.15 ± 45.30 (405 to 616)	<0.001	^†0.965 ^‡0.070
Residual stroma (μm)	359.33 ± 46.69 (302 to 446)			369.53 ± 30.84 (321 to 430)			0.147

SD: standard deviation; RE: refractive error; D: diopter; MRSE: manifest refraction spherical equivalent; BCVA: best corrected visual acuity; K: keratometry; IOP: intraocular pressure; CCT: central corneal thickness; ^†the comparison of the preoperative values; ^‡the comparison of the postoperative values.