Clinical Outcomes of SMILE With a Triple Centration Technique and Corneal Wavefront-Guided Transepithelial PRK in High Astigmatism
Abstract
PURPOSE:
To comparatively investigate the clinical outcomes, vector parameters, and corneal aberrations of small incision lenticule extraction (SMILE) with a triple centration technique and corneal wavefront-guided transepithelial photorefractive keratectomy (PRK) for the correction of high astigmatism.
METHODS:
This retrospective, comparative case series study included 89 eyes (89 patients) that received treatment for myopia with high astigmatism (≥ 2.50 diopters) using SMILE with a triple centration technique (SMILE group; 45 eyes) and corneal wavefront-guided transepithelial PRK (transepithelial PRK group; 44 eyes). Visual acuity measurement, manifest refraction, slit-lamp examination, autokeratometry, corneal topography, and evaluation of corneal wavefront aberration were performed preoperatively and at 1, 3, and 6 months after surgery. The safety, efficacy, vector parameters, and corneal aberrations at 6 months after surgery were compared between the two groups.
RESULTS:
At 6 months after surgery, the transepithelial PRK and SMILE groups exhibited comparable mean uncorrected distance visual acuities (−0.06 ± 0.07 and −0.05 ± 0.07 logMAR, respectively), safety, efficacy, and predictability of refractive and visual outcomes. There was a slight but statistically significant difference in the correction index between the transepithelial PRK and SMILE groups (0.96 ± 0.11 and 0.91 ± 0.10, respectively). Whereas the transepithelial PRK group exhibited increased corneal spherical aberration and significantly reduced corneal coma and trefoil, no changes in aberrometric values were noted in the SMILE group.
CONCLUSIONS:
Both SMILE with a triple centration technique and corneal wavefront-guided transepithelial PRK are effective and provide predictable outcomes for the correction of high myopic astigmatism, although slight undercorrection was observed in the SMILE group. The triple centration technique was helpful in astigmatism correction by SMILE.
[J Refract Surg. 2018;34(3):156–163.]
- 1.Liu YC, Rosman M, Mehta JS. Enhancement after small-incision lenticule extraction: incidence, risk factors, and outcomes. Ophthalmology. 2017; 124:813–821.
10.1016/j.ophtha.2017.01.053 Crossref Medline, Google Scholar - 2.Moshirfar M, McCaughey MV, Reinstein DZ, Shah R, Santiago-Caban L, Fenzl CR. Small-incision lenticule extraction. J Cataract Refract Surg. 2015; 41:652–665.
10.1016/j.jcrs.2015.02.006 Crossref Medline, Google Scholar - 3.Chan C, Lawless M, Sutton G, Versace P, Hodge C. Small incision lenticule extraction (SMILE) in 2015. Clin Exp Optom. 2016; 99:204–212.
10.1111/cxo.12380 Crossref Medline, Google Scholar - 4.Kamiya K, Shimizu K, Igarashi A, Kobashi H. Visual and refractive outcomes of femtosecond lenticule extraction and small-incision lenticule extraction for myopia. Am J Ophthalmol. 2014; 157:128–134.
10.1016/j.ajo.2013.08.011 Crossref Medline, Google Scholar - 5.Shah R, Shah S, Sengupta S. Results of small incision lenticule extraction: all-in-one femtosecond laser refractive surgery. J Cataract Refract Surg. 2011; 37:127–137.
10.1016/j.jcrs.2010.07.033 Crossref Medline, Google Scholar - 6.Sekundo W, Kunert KS, Blum M. Small incision corneal refractive surgery using the small incision lenticule extraction (SMILE) procedure for the correction of myopia and myopic astigmatism: results of a 6 month prospective study. Br J Ophthalmol. 2011; 95:335–339.
10.1136/bjo.2009.174284 Crossref Medline, Google Scholar - 7.Agca A, Demirok A, Yildirim Y, Refractive lenticule extraction (ReLEx) through a small incision (SMILE) for correction of myopia and myopic astigmatism: current perspectives. Clin Ophthalmol. 2016; 10:1905–1912.
10.2147/OPTH.S80412 Crossref Medline, Google Scholar - 8.Piñero DP, Teus MA. Clinical outcomes of small-incision lenticule extraction and femtosecond laser-assisted wavefront-guided laser in situ keratomileusis. J Cataract Refract Surg. 2016; 42:1078–1093.
10.1016/j.jcrs.2016.05.004 Crossref Medline, Google Scholar - 9.Fadlallah A, Fahed D, Khalil K, Transepithelial photorefractive keratectomy: clinical results. J Cataract Refract Surg. 2011; 37:1852–1857.
10.1016/j.jcrs.2011.04.029 Crossref Medline, Google Scholar - 10.Aslanides IM, Padroni S, Arba Mosquera S, Ioannides A, Mukherjee A. Comparison of single-step reverse transepithelial all-surface laser ablation (ASLA) to alcohol-assisted photorefractive keratectomy. Clin Ophthalmol. 2012; 6:973–980.
10.2147/OPTH.S32374 Crossref Medline, Google Scholar - 11.Luger MH, Ewering T, Arba-Mosquera S. Consecutive myopia correction with transepithelial versus alcohol-assisted photorefractive keratectomy in contralateral eyes: one-year results. J Cataract Refract Surg. 2012; 38:1414–1423.
10.1016/j.jcrs.2012.03.028 Crossref Medline, Google Scholar - 12.Jun I, Kang DS, Tan J, Comparison of clinical outcomes between wavefront-optimized versus corneal wavefront-guided transepithelial photorefractive keratectomy for myopic astigmatism. J Cataract Refract Surg. 2017; 43:174–182.
10.1016/j.jcrs.2016.11.045 Crossref Medline, Google Scholar - 13.Ji YW, Kim M, Kang DSY, Lower laser energy levels lead to better visual recovery after small-incision lenticule extraction: prospective randomized clinical trial. Am J Ophthalmol. 2017; 179:159–170.
10.1016/j.ajo.2017.05.005 Crossref Medline, Google Scholar - 14.Alpins N. Astigmatism analysis by the Alpins method. J Cataract Refract Surg. 2001; 27:31–49.
10.1016/S0886-3350(00)00798-7 Crossref Medline, Google Scholar - 15.Reinstein DZ, Archer TJ, Randleman JB. JRS standard for reporting astigmatism outcomes of refractive surgery. J Refract Surg. 2014; 30:654–659.
10.3928/1081597X-20140903-01 Link, Google Scholar - 16.Zhang J, Wang Y, Wu W, Xu L, Li X, Dou R. Vector analysis of low to moderate astigmatism with small incision lenticule extraction (SMILE): results of a 1-year follow-up. BMC Ophthalmol. 2015; 15:8.
10.1186/1471-2415-15-8 Crossref Medline, Google Scholar - 17.Kaluzny BJ, Cieslinska I, Mosquera SA, Verma S. Single-step transepithelial PRK vs alcohol-assisted PRK in myopia and compound myopic astigmatism correction. Medicine (Baltimore). 2016; 95:e1993.
10.1097/MD.0000000000001993 Crossref Medline, Google Scholar - 18.Adib-Moghaddam S, Soleyman-Jahi S, Salmanian B, Single-step transepithelial photorefractive keratectomy in myopia and astigmatism: 18-month follow-up. J Cataract Refract Surg. 2016; 42:1570–1578.
10.1016/j.jcrs.2016.08.029 Crossref Medline, Google Scholar - 19.Antonios R, Abdul Fattah M, Arba Mosquera S, Abiad BH, Sleiman K, Awwad ST. Single-step transepithelial versus alcohol-assisted photorefractive keratectomy in the treatment of high myopia: a comparative evaluation over 12 months. Br J Ophthalmol. 2017; 101:1106–1112.
10.1136/bjophthalmol-2016-309409 Crossref Medline, Google Scholar - 20.Adib-Moghaddam S, Soleyman-Jahi S, Adili-Aghdam F, Arba Mosquera S, Hoorshad N, Tofighi S. Single-step transepithelial photorefractive keratectomy in high myopia: qualitative and quantitative visual functions. Int J Ophthalmol. 2017; 10:445–452. Medline, Google Scholar
- 21.Pedersen IB, Ivarsen A, Hjortdal J. Changes in astigmatism, densitometry, and aberrations after SMILE for low to high myopic astigmatism: a 12-month prospective study. J Refract Surg. 2017; 33:11–17.
10.3928/1081597X-20161006-04 Link, Google Scholar - 22.Zhang J, Wang Y, Chen X. Comparison of moderate- to high-astigmatism corrections using wavefront-guided laser in situ keratomileusis and small-incision lenticule extraction. Cornea. 2016; 35:523–530.
10.1097/ICO.0000000000000782 Crossref Medline, Google Scholar - 23.Swami AU, Steinert RF, Osborne WE, White AA. Rotational malposition during laser in situ keratomileusis. Am J Ophthalmol. 2002; 133:561–562.
10.1016/S0002-9394(01)01401-5 Crossref Medline, Google Scholar - 24.Kim H, Joo CK. Ocular cyclotorsion according to body position and flap creation before laser in situ keratomileusis. J Cataract Refract Surg. 2008; 34:557–561.
10.1016/j.jcrs.2007.11.030 Crossref Medline, Google Scholar - 25.Chan TC, Ng AL, Cheng GP, Vector analysis of astigmatic correction after small-incision lenticule extraction and femto-second-assisted LASIK for low to moderate myopic astigmatism. Br J Ophthalmol. 2016; 100:553–559.
10.1136/bjophthalmol-2015-307238 Crossref Medline, Google Scholar - 26.Yu M, Chen M, Wang B, Zou L, Zhu X, Dai J. Comparison of visual quality after SMILE and LASEK for mild to moderate myopia. J Refract Surg. 2015; 31:795–800.
10.3928/1081597X-20151111-02 Link, Google Scholar - 27.Lee JK, Chuck RS, Park CY. Femtosecond laser refractive surgery: small-incision lenticule extraction vs. femtosecond laser-assisted LASIK. Curr Opin Ophthalmol. 2015; 26:260–264.
10.1097/ICU.0000000000000158 Crossref Medline, Google Scholar

