Photorefractive Keratectomy for Residual Myopia after Myopic Laser In Situ Keratomileusis

Table 1

Preoperative and 12-month postoperative data of eyes included in the study.

	Before PRK; Mean ± SD (range)	12 months after PRK; Mean ± SD (range)	value
Spherical error	D (−0.75–0.75 D)	D (+0.50 to −0.50 D)	<0.0
Astigmatism	D (0.00–3.00 D)	D (0.25–2.25 D)	>0.05
Uncorrected visual acuity	(0.1–0.7)	(0.6–1.00)	<0.0
Best corrected visual acuity	(0.8–1.00)	(0.8–1.00)	>0.05
Central corneal thickness	µm (389–412 µm)	µm (379–384 µm)	>0.05
Corneal hysteresis	(8.5–9.1)	(8.3–9.0)	>0.05
Corneal resistance factor	(7.0–8.0)	(7.0–7.8)	>0.05
Total high-order aberrations	µm (0.23–0.47 µm)	µm (0.21–0.50 µm)	>0.05
Coma	µm (0.24–0.31 µm)	µm (0.20–0.32 µm)	>0.05
Spherical aberrations	µm (0.27–0.24 µm)	µm (0.22–0.24 µm)	>0.05

means significant result.