Long-Term Results of Excimer Laser Surface Ablation with Smoothing for High Myopia
DOI:
https://doi.org/10.12974/2309-6136.2017.05.01Keywords:
High myopia, excimer laser, PRK, smoothing, long-term results.Abstract
Purpose: To evaluate long-term refractive, aberrometric and anatomical results of surface ablation plus corneal PTK-style smoothing for myopia greater than –7.00 D.
Methods: One-hundred-and-fourteen eyes of 69 patients (mean age: 37.7 ± 8.3 years) underwent PRK with the NIDEK EC-5000 excimer laser (NIDEK Co. Ltd., Gamagori, Japan) using multiple optical zones ranging in diameter from 4.89 mm to 7.0 mm, and transition zones (TZ) that were at least 3 mm wider than the optical zones (OZ). A cross-cylinder technique was used for treating astigmatism greater than 0.50 D. All eyes underwent a phototherapeutic keratectomy (PTK) smoothing technique using masking fluid. The Student’s t-test was used to determine a statistically significant change after surgery. A p value less than 0.05 was considered statistically significant.
Results: Preoperative corrected distance visual acuity (CDVA) was 0.88 ± 0.16 with –9.53 ± 1.18 D cycloplegic spherical equivalent (SE). Preoperative corneal pachymetry was 560.4 ± 30.1 µ. Three years after surgery uncorrected visual acuity (UCVA) was 0.79 ± 0.26, CDVA was 0.92 ± 0.19 with –0.56 ± 0.90 D SE. Mean corneal haze was highest 1 month after surgery (0.58 ± 0.35), then progressively decreased to 0.11 ± 0.32 by 3 months postoperatively. Following year one, refraction and corneal curvature remained stable. There were no cases of keractasia to date. There was no hyperopic induction due to PTK. Two eyes required retreatment due to undercorrection. Total wavefront error did not change significantly, while astigmatism decreased and coma increased (both with p< 0.001).
Conclusion: Surface ablation for the treatment of high myopia using PTK smoothing with a masking fluid was safe and effective. Wide optical and transition zones prevented induction of spherical aberration and the incorporation of the smoothing technique created a regular corneal surface with regular healing and trace to no haze after surgery.
References
Pop M, Payette Y. Multipass versus single pass photorefractive keratectomy for high myopia using a scanning laser. J Refract Surg 1999; 15: 444-50.
Taneri S, Zieske JD, Azar DT. Evolution, techniques, clinical outcomes, and pathophysiology of LASEK: Review of the literature. Surv Ophthalmol 2004; 49: 576-602. https://doi.org/10.1016/S0039-6257(04)00135-3
Yu EYW, Jackson WB. Recent advances in refractive surgery CMAJ 1999; 160 (9).
Kermani O, Schmiedt K, Oberheide U, Gerten G. Topographic- and wavefront-guided customized ablations with the NIDEK-EC5000CXII in LASIK for myopia. J Refract Surg 2006; 22: 754-63.
Hori-Komai Y, Toda I, Asano-Kato N, Ito M, Yamamoto T, Tsubota K. Comparison of LASIK using the NIDEK EC-5000 optimized aspheric transition zone (OATz) and conventional ablation profile. J Refract Surg 2006; 22: 546-55.
Nakano EM, Bains HS, Hirai FE, Portellinha W, Oliveira M, Nakano K. Comparison of laser epithelial keratomileusis with and without mitomycin C for wavefront customized surface ablations. J Refract Surg 2007; 23: S1021-8.
Vinciguerra P, Camesasca FI, Ponzin D. Use of amino acids in refractive surgery. J Refract Surg 2002; 18: S374-7.
Vinciguerra P, Azzolini M, Airaghi P, Radice P, De Molfetta V. Effect of decreasing surface and interface irregularities after photorefractive keratectomy and laser in situ keratomileusis on optical and functional outcomes. J Refract Surg 1998; 14: S199-203.
Netto MV, Dupps W Jr, Wilson SE. Wavefront-guided ablation: evidence for efficacy compared to traditional ablation. Am J Ophthalmol 2006; 141: 360-368. https://doi.org/10.1016/j.ajo.2005.08.034
Huang D, Tang M, Shekhar R. Mathematical model of corneal surface smoothing after laser refractive surgery. Am J Ophthalmol 2003; 135: 267-78. https://doi.org/10.1016/S0002-9394(02)01942-6
Epstein D, Fagerholm P, Hamberg-Nyström H, Tengroth B . Twenty-four-month follow-up of excimer laser photorefractive keratectomy for myopia. Refractive and visual acuity results. Ophthalmology 1994; 101: 1558-64. https://doi.org/10.1016/S0161-6420(94)31150-X
Vinciguerra P, Albè E, Camesasca FI, Trazza S, Epstein D. Wavefront- versus topography-guided customized ablations with the NIDEK EC-5000 CX II in surface ablation treatment: refractive and aberrometric outcomes. J Refract Surg 2007; 23: S1029-36.
Vinciguerra P, Camesasca FI, Nizzola G, Epstein D. Treatment of astigmatism In: Vinciguerra P, Camesasca FI, eds. Refractive Surface Ablation: PRK, LASEK, Epi-LASIK, Custom, PTK and Retreatment. 1st ed. Thorofare, NJ: SLACK Inc 2007; pp. 97-102.
Vinciguerra P, Sborgia M, Epstein D, Azzolini M, MacRae S. Photorefractive keratectomy to correct myopic or hyperopic astigmatism with a cross-cylinder ablation. J Refract Surg 1999; 15(2 Suppl): S183-5.
Vinciguerra P, Camesasca F. Smoothing in Excimer Refractive Surgery: The Quest for a Regular Ablated Surface. In: Vinciguerra P, Camesasca FI, eds. Refractive Surface Ablation: PRK, LASEK, Epi-LASIK, Custom, PTK and Retreatment. 1st ed. Thorofare, NJ: SLACK Inc 2007; pp. 87-95.
Buratto L, Ferrari M. Photorefractive keratectomy for myopia from 6.00 D to 10.00 D. Refract Corneal Surg 1993; 9(2 Suppl): S34-6.
Holladay JT, Janes JA. Topographic changes in corneal asphericity and effective optical zone after laser in situ keratomileusis. J Cataract Refract Surg 2002; 28(6): 942-7. https://doi.org/10.1016/S0886-3350(02)01324-X
Netto MV, Mohan RR, Sinha S, Sharma A, Dupps W, Wilson SE. Stromal haze, myofibroblasts, and surface irregularity after PRK. Exp Eye Res 2006; 82(5): 788-97. https://doi.org/10.1016/j.exer.2005.09.021
Møller-Pedersen T, Cavanagh HD, Petroll WM, Jester JV. Corneal haze development after PRK is regulated by volume of stromal tissue removal. Cornea 1998; 17(6): 627-39. https://doi.org/10.1097/00003226-199811000-00011
Qazi MA, Roberts CJ, Mahmoud AM, Pepose JS. Topographic and biomechanical differences between hyperopic and myopic laser in situ keratomileusis. J Cataract Refract Surg 2005; 31(1): 48-60. https://doi.org/10.1016/j.jcrs.2004.10.043
Langrová H, Derse M, Hejcmanová D, Feuermannová A, Rozsíval P, Hejcmanová M. Effect of photorefractive keratectomy and laser in situ keratomileusis in high myopia on logMAR visual acuity and contrast sensitivity. Acta Medica (Hradec Kralove) 2003; 46(1): 15-8.
Gambato C, Miotto S, Cortese M, Ghirlando A, Lazzarini D, Midena E. Mitomycin C-assisted photorefractive keratectomy in high myopia: a long-term safety study. Cornea 2011; 30(6): 641-5. https://doi.org/10.1097/ICO.0b013e31820123c8
Anschutz T, Pieger S. Correlation of laser profilometry scans with clinical results. J Refract Surg 1999; 15(2): S252-6.
Vinciguerra P, Azzolini M, Radice P, Sborgia M, De Molfetta V. A method for examining surface and interface irregularities after photorefractive keratectomy and laser in situ keratomileusis: predictor of optical and functional outcomes. J Refract Surg 1998; 14: S204–S206.
Serrao S, Lombardo M, Mondini F. Photorefractive keratectomy with and without smoothing: a bilateral study. J Refract. Surg 2003; 19: 58–64.
Netto MV, Mohan RR, Sinha S, Sharma A, Dupps W, Wilson SE. Stromal haze, myofibroblasts, and surface irregularity after PRK. Exp Eye Res 2006; 82(5): 788-97. https://doi.org/10.1016/j.exer.2005.09.021
Vinciguerra P, Camesasca FI, Vinciguerra R, Arba-Mosquera S, Torres I, Morenghi E, Randleman JB. Advanced Surface Ablation With a New Software for the Reduction of Ablation Irregularities. J Refract Surg 2017; 33(2): 89-95. https://doi.org/10.3928/1081597X-20161122-01
Vinciguerra P, Sborgia M, Epstein D; Azzolini M, McRae S Photorefractive keratectomy to correct myopic or hyperopic astigmatism with a cross-cylinder ablation. J Refract Surg 1999; 15 (S) 183-5.
Rosman M, Alió JL, Ortiz D, Perez-Santonja JJ. Comparison of LASIK and photorefractive keratectomy for myopia from - 10.00 to -18.00 diopters 10 years after surgery. J Refract Surg 2010; 26(3): 168-76. https://doi.org/10.3928/1081597X-20100224-02
Vestergaard AH, Hjortdal JØ, Ivarsen A, Work K, Grauslund J, Sjølie AK. Long-term outcomes of photorefractive keratectomy for low to high myopia: 13 to 19 years of followup. J Refract Surg 2013; 29(5): 312-9. https://doi.org/10.3928/1081597X-20130415-02
Alio JL, Soria FA, Abbouda A, Peña-García P. Fifteen years follow-up of photorefractive keratectomy up to 10 D of myopia: outcomes and analysis of the refractive regression. Br J Ophthalmol 2016; 100(5): 626-32. https://doi.org/10.1136/bjophthalmol-2014-306459
