Purpose: To present the clinical results of epi-LASIK in a high myopia and myopic astigmatic population followed for more than 1 year. Methods: This retrospective study comprised 67 eyes of 52 patients who underwent epi-LASIK for the correction of high myopia and myopic astigmatism. Epi-LASIK was performed with an automatically rotational epikeratome (KM-5000D, Wuxi Kangming Medical Device Corp., Wuxi, China) and the MEL80 (Carl Zeiss Meditec, Jena, Germany) excimer laser. The postoperative symptom, epithelial flap, vision, refraction and haze formation were investigated. The astigmatic change was calculated by the Alpins vector analysis method. Results: The follow-up period was 13.27 months. Mean preoperative spherical equivalent (SE) refraction and cylinder were –13.39 diopters (D) and –2.02 D. An integrated epithelial sheet with a diameter of about 8–9 mm was made in 65 (97.01%) eyes leaving a superior hinge of approximately 2–4 mm. The mean epithelial healing time was 5.55 days. More than 1 year after the treatment, no eye lost more than 1 line of best spectacle-corrected visual acuity. The mean SE and cylinder were –2.25 and –0.79 D. The mean astigmatism correction index was 1.06. The index of success of 0.51 reflected a 49% success in achieving cylinder correction. The change induced by the laser ablation at the intended axis of cylinder reduction was 93%. At the same interval, 7.46% of eyes had trace haze and others were clear. Haze did not affect the visual acuity in any eye. Conclusions: Epi-LASIK appeared to be effective and safe in the treatment of high myopia and myopic astigmatism with the advantages of having lower postoperative pain and satisfactory refractive and visual outcome postoperatively.

Keywords:
Epi-LASIK, High myopia, Astigmatism
1.
Cimberle M: LASEK may offer the advantages of both LASIK and PRK. Ocul Surg News 1999;17:28.
2.
Wilson SE, Mohan RR, Hong JW, et al: The wound healing response after laser in situ keratomileusis and photorefractive keratectomy; elusive control of biological variability and effect on custom laser vision correction. Arch Ophthalmol 2001;119:889–896.
3.
Azar DT, Taneri S, Chun CC: Laser subepithelial keratomileusis (LASEK): review and clinicopathological correlations. MEJO 2002;10:54–59.
4.
Pallikaris IG, Naoumidi II, Kalyvianaki MI, et al: Comparative histological evaluation of mechanical and alcohol-assisted epithelial separation. J Cataract Refract Surg 2003;29:1496–1501.
5.
Gabler B, Winkler von Mohrenfelds C, Dreiss AK, et al: Vitality of epithelial cells after alcohol exposure during laser-assisted subepithelial keratectomy flap preparation. J Cataract Refract Surg 2002;28:1841–1846.
6.
Kim SY, Sah WJ, Lim YW, Hahn TW: Twenty percent alcohol toxicity on rabbit corneal epithelial cells: electron microscopic study. Cornea 2002;21:388–392.
7.
Chen CC, Chang JH, Lee JB, et al: Human corneal epithelial cell viability and morphology after dilute alcohol exposure. Invest Ophthalmol Vis Sci 2002;43:2593–2602.
8.
Stramer BM, Zieske JD, Jung JC, et al: Molecular mechanisms controlling the fibrotic repair phenotype in cornea: implications for surgical outcomes. Invest Ophthalmol Vis Sci 2003;44:4237–4246.
9.
Pallikaris IG, Kalyvianaki MI, Katsanevaki VJ, et al: Epi-LASIK: preliminary clinical results of an alternative surface ablation procedure. J Cataract Refract Surg 2005;31:879–885.
10.
Katsanevaki VJ, Kalyvianaki MI, Kavroulaki DS, Pallikaris IG: One-year clinical results after epi-LASIK for myopia. Ophthalmology 2007;114:1111–1117.
11.
Chen CD, Chu RY, Dai JH, Zhou XT: An experimental study on the separation of human corneal epithelium with different blade edge sharpness of the ultra-thin microkeratome. Chin J Ophthalmol Otorhinolaryngol 2004;4:211–213.
12.
Dai JH, Chu RY, Zhou XT, et al: One-year outcomes of epi-LASIK for myopia. J Refract Surg 2006;22:589–595.
13.
Koch D: How should we analyze astigmatic data? J Cataract Refract Surg 2001;27:1–3.
14.
Koch D: Reporting astigmatism data. J Cataract Refract Surg 1998;24:1545.
15.
Koch D: Excimer laser technology: new options coming to fruition. J Cataract Refract Surg 1997;23:1429–1430.
16.
Koch D, Kohnen T, Ostbaum SA, Rosen ES: Format for reporting refractive surgical data. J Cataract Refract Surg 1998;24:285–287.
17.
Alpins NA: Vector analysis of astigmatism changes by flattening, steepening, and torque. J Cataract Refract Surg 1997;23:1503–1514.
18.
Winkler von Mohrenfels C, Reischl U, Lohmann CP: Corneal haze after photorefractive keratectomy for myopia: role of collagen IV mRNA typing as a predictor of haze. J Cataract Refract Surg 2002;28:1446–1451.
19.
Netto MV, Mohan RR, Ambrosio R Jr, et al: Wound healing in the cornea: a review of refractive surgery complications and new prospects for therapy. Cornea 2005;24:509–522.
20.
Katsanevaki VJ, Naoumidi II, Kalyvianaki MI, Pallikaris IG: Epi-LASIK: histological findings of separated epithelial sheets 24 hours after treatment. J Refract Surg 2006;22:151–154.
21.
Pallikaris IG, Katsanevaki VJ, Kalyvianaki MI, Naoumidi II: Advances in subepithelial excimer refractive surgery techniques: epi-LASIK. Curr Opin Ophthalmol 2003;14:207–212.
22.
Donnefeld E: Visual results and light microscopic evaluation of human corneal epithelium and stroma following epi-LASIK. XXIII Congress of ESCRS, Lisbon 2005.
23.
Long Q, Chu RY, Zhou XT, et al: Correlation between TGF-β1 in tears and corneal haze following LASEK and epi-LASIK. J Refract Surg 2006;22:708–712.
24.
Dai JH, Chen CD, Chu RY, et al: Clinical investigation of epipolis laser in situ keratomileusis on high myopia. Chin J Ophthalmol 2005;41:211–215.
25.
Zhou XT, Chu RY, Wang XY, et al: The clinical study of the epithelial flap of painless LASEK and Epi-LASIK. Chin J Ophthalmol 2005;41:977–980.
26.
Applegate RA, Howland HC: Magnification and visual acuity in refractive surgery. Arch Ophthalmol 1993;111:1335–1342.
27.
Kim JK, Kim SS, Lee HK, et al: Laser in situ keratomileusis versus laser-assisted subepithelial keratectomy for the correction of high myopia. J Cataract Refract Surg 2004;30:1405–1411.
28.
Sekundo W, Bonicke K, Mattausch P, Wiegand W: Six-year follow-up of laser in situ keratomileusis for moderate and extreme myopia using a first-generation excimer laser and microkeratome. J Cataract Refract Surg 2003;29:1152–1158.
29.
O’Doherty M, O’Keeffe M, Kelleher C: Five-year follow-up of laser in situ keratomileusis for all levels of myopia. Br J Ophthalmol 2006;90:20–23.
30.
Kymionis GD, Tsiklis NS, Astyrakakis N: Eleven-year follow-up of laser in situ keratomileusis. J Cataract Refract Surg 2007;33:191–196.
31.
Pallikaris IG, Siganos DS: Excimer laser in situ keratomileusis and photorefractive keratectomy for correction of high myopia. J Refract Corneal Surg 1994;10:498–510.
32.
Knorz MC, Liermann A, Seiberth V, et al: Laser in situ keratomileusis to correct myopia of –6.00 to –29.0 diopters. J Refract Surg 1996;12:575–584.
33.
Dada T, Sudan R, Sinha R: Results of laser in situ keratomileusis for myopia of –10 to –19 diopters with a Technolas 217 laser. J Refract Surg 2003;19:44–47.
34.
McGhee CN, Craig JP, Sachdev N, et al: Functional, psychological, and satisfaction outcomes of laser in situ keratomileusis for high myopia. J Cataract Refract Surg 2000;26:497–509.
35.
Magallanes R, Shah S, Zadok D, et al: Stability after laser in situ keratomileusis in moderately and extremely myopic eyes. J Cataract Refract Surg 2001;7:1007–1012.
36.
Chayet AS, Assil KK, Montes M, et al: Regression and its mechanism after laser in situ keratomileusis in moderate and high myopia. Ophthalmology 1998;105:1194–1199.
37.
Baldwin HC, Marshall J: Growth factors in corneal wound healing following refractive surgery: a review. Acta Ophthalmol Scand 2002;80:238–247.
38.
Kaji Y, Soya K, Amano S, et al: Relation between corneal haze and transforming growth factor-β1 after photorefractive keratectomy and laser in situ keratomileusis. J Cataract Refract Surg 2001;27:1840–1846.
39.
Fong CS: Refractive surgery: the future of perfect vision? Singapore Med J 2007;48:709–719.
© 2008 S. Karger AG, Basel
2008
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.