Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing 100730, China
Objective To evaluate the clinical results of transepithelial photorefractive keratectomy (TPRK) in the treatment of myopia. Methods Thirty-eight patients (72 eyes) who were diagnosed with myopia and astigmatism underwent TPRK and 34 patients (64 eyes) who underwent LASEK were enrolled in the study. Ablations were performed with the Schwind Amaris system. The time frame for epithelial healing and ocular pain score were recorded on 1, 3 and 10 d. The patients were examined at 10 d and at 1, 3 and 6 months postoperatively to measure uncorrected distance visual acuity (UDVA), spherical equivalent (SE), corneal haze and corneal confocal microscopy (CCM). The data were analyzed with a Mann-Whitney U test, chi-square test, independent t test and RMANOVA. Results The mean time for epithelial healing was significantly shorter after TPRK than after LASEK (2.3±1.2 versus 3.3±1.9 days) (t=8.659, P<0.01). At 1 d and 3 d, the difference in the mean pain scores was not significant (Z=0.683, -0.380, P>0.05). At 3 d, more eyes had achieved 1.0 or better in the TPRK group than in the LASEK group (35% versus 13%)(χ2=9.105, P<0.01). At 10 d, the mean SE was smaller in the TPRK group than in the LASEK group (F=5.691, P<0.05), but the difference in SE was not significant at 1, 3 and 6 months. All LASEK- and TPRK-treated eyes equaled or bettered UCVA and BCVA. There was no clinically severe haze but any haze tended to dissipate after 6 months. There was no significant difference in the grade of haze between the two surgeries. A high number of reflective pieces and keratocyte activation could be observed under CCM and were obviously more significant in LASEK- than in TPRK-treated eyes at 1 month. Alleviation was gradual. Conclusion TPRK for myopia is as safe and effective as LASEK. It appears to induce a shorter time for wound healing and UCVA improvement in the early postoperative period.
Randleman JB, Russell B, Ward MA, et al. Risk factors and prognosis for corneal ectasia after LASIK[J]. Ophthalmology,2003,110(2):267-275.
[4]
Fraunfelder FW, Wilson SE. Laser in situ keratomileusis versus photorefractive keratectomy in the correction of myopic astigmatism[J]. Cornea,2001,20(4):385-387.
[5]
Pedrotti E, Sbabo A, Marchini G. Customized transepithelial photorefractive keratectomy for iatrogenic ametropia after penetrating or deep lamellar keratoplasty[J]. J Cataract Refract Surg,2006,32(8):1288-1291.
[6]
Camellin M, Arba Mosquera S. Simultaneous aspheric wavefront-guided transepithelial photorefractive keratectomy and phototherapeutic keratectomy to correct aberrations and refractive errors after corneal surgery[J]. J Cataract Refract Surg,2010,36(7):1173-1180.
Jain VK, Abell TG, Bond WI, et al. Immediate transepithelial photorefractive keratectomy for treatment of laser in situ keratomileusis flap complications[J]. J Refract Surg,2002,18(2):109-112.
[9]
Korkmaz S, Bilgihan K, Sul S, et al. A clinical and confocal microscopic comparison of transepithelial PRK and LASEK for myopia[J]. J Ophthalmol,2014,2014:784185.
[10]
Celik U, Bozkurt E, Celik B, et al. Pain, wound healing and refractive comparison of mechanical and transepithelial debridement in photorefractive keratectomy for myopia: Results of 1 year follow-up[J]. Cont Lens Anterior Eye,2014,37(6):420-426.
[11]
Lee HK, Lee KS, Kim JK, et al. Epithelial healing and clinical outcomes in excimer laser photorefractive surgery following three epithelial removal techniques: mechanical, alcohol, and excimer laser[J]. Am J Ophthalmol,2005,139(1):56-63.
[12]
Sher NA, Hardten DR, Fundingsland B, et al. 193-nm excimer photorefractive keratectomy in high myopia[J]. Ophthalmology,1994,101(9):1575-1582.
[13]
Williams DK. Excimer laser photorefractive keratectomy for extreme myopia[J]. J Cataract Refract Surg,1996,22(7):910-914.
[14]
Shah S, Sebai Sarhan AR, Doyle SJ, et al. The epithelial flap for photorefractive keratectomy[J]. Br J Ophthalmol,2001,85(4):393-396.