Single-step transepithelial ASLA (SCHWIND) with mitomycin-C for the correction of high myopia: long term follow-up

Figures & data

Table 1 Reverse single-step tPRK for high myopia: baseline values and operative factors compared to PRK and LASIK control groups

Baseline preoperative values	tPRK	PRK	LASIK	P-value (tPRK vs PRK)	P-value (tPRK vs LASIK)
Number of eyes	41	29	31
Mean preoperative SE (D ± SD)	−7.89 (1.24)	−8.25 (1.72)	−7.41 (1.35)	0.28	0.13
Mean preoperative logMAR CDVA (± SD)	0.032 (0.05)	0.04 (0.07)	0.03 (0.06)	0.58	0.97
Mean age (years)	27 (6)	27 (7)	31.3 (10)	0.75	0.03
Central pachymetry (μm)	536 (30)	530 (29)	551 (23)	0.387	0.02
Mean keratometry (D)	44.25 (1.44)	44.02 (1.43)	43.3 (3.7)	0.49	0.20
Mean optical zone (mm)	6.03 (0.19)	6.10 (0.15)	6.27 (0.22)	0.14	<0.001
Stromal ablation depth (μm)	105 (14)	111 (14)	113 (13)	0.06	<0.001

Abbreviations: CDVA, corrected distance visual acuity; D, diopters; LASIK, laser-assisted in situ keratomileusis; logMAR, logarithm of the minimum angle of resolution; PRK, photorefractive keratectomy; SD, standard deviation; SE, spherical equivalent; tPRK, transepithelial PRK; vs, versus.

Figure 1 Cumulative proportion of eyes achieving Snellen visual acuity targets at 12 months after transepithelial photorefractive keratectomy (tPRK), laser-assisted in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK).

Abbreviations: LASIK, laser-assisted in situ keratomileusis; PRK, photorefractive keratectomy; tPRK, transepithelial PRK; UDVA, uncorrected distance visual acuity.

Figure 2 Proportion of eyes gaining or losing best-corrected Snellen visual acuity at 12 months after transepithelial photorefractive keratectomy, laser-assisted in situ keratomileusis, and photorefractive keratectomy.

Abbreviations: CDVA, corrected distance visual acuity; LASIK, laser-assisted in situ keratomileusis; PRK, photorefractive keratectomy; tPRK, transepithelial PRK.

Table 2 Reverse single-step transepithelial PRK for high myopia: visual and refractive outcomes compared to PRK and LASIK control groups

	tPRK	PRK	LASIK	P-value (tPRK vs PRK)	P-value (tPRK vs LASIK)
Efficacy and safety at 12 months
Number of eyes	35	28	31
Postoperative logMAR UDVA (SD)	0.00 (0.05)	0.06 (0.1)	0.05 (0.09)	0.01	0.008
20/25 equivalent or better UDVA (%)	97.1	75.0	87.1	0.51	0.02
20/20 equivalent or better UDVA (%)	77.1	60.7	48.3	0.30	0.09
Loss of 2 or more lines CDVA (%)	0	14.3	0	0.03	1
Refractive outcomes 12 months postoperatively
Mean postoperative SE, D (SD)	−0.10 (0.34)	−0.20 (0.59)	−0.08 (0.36)	0.4	0.72
% within ±0.5 D target	91.4	85.7	83.9	0.68	0.45
% within ±1.0 D target	97.1	89.3	100	0.31	1

Abbreviations: CDVA, corrected distance visual acuity; D, diopters; LASIK, laser-assisted in situ keratomileusis; logMAR, logarithm of the minimum angle of resolution; SD, standard deviation; SE, spherical equivalent; PRK, photorefractive keratectomy; tPRK, transepithelial PRK; UDVA, uncorrected distance visual acuity; vs, versus.

Figure 3 Postoperative spherical equivalent subjective refraction in eyes with plano target refraction at 12 months after transepithelial photorefractive keratectomy (tPRK), laser-assisted in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK).

Figure 4 Postoperative subjective refractive astigmatism at 12 months after transepithelial photorefractive keratectomy (tPRK), laser-assisted in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK).

Figure 5 Postoperative achieved vs attempted spherical equivalent refraction at 12 months after transepithelial photorefractive keratectomy (tPRK), laser-assisted in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK).

Note: The dots within the green lines indicate patients that achieved spherical equivalent (SE) within ±0.5D; and the dots within the purple lines indicates the patients that achieved SE within ±1.0D.

Figure 6 Temporal stability of spherical equivalent refractive correction at postoperative time points after transepithelial photorefractive keratectomy (tPRK), laser-assisted in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK).

Notes: Numbers in parenthesis are the patients that attended for follow-up at the specific time point. The circles indicate mean SE and the error bars indicate SD values.
Abbreviations: Pre, preoperative; SD, standard deviation; SE, spherical equivalent.