Management of Post Lasik Residual Myopic Astigmatism: Evaluation of Two Different Techniques

Abstract Background: This study to evaluate two different tech-niques which are femtosecond lasik and transepithelial pho-torefractive keratotomy in management of post lasik residual myopic astigmatism. In both techniques we calculate the central corneal thickness, preoperative refractive errors SER, preoperative UDVA, CDVA, and postoperative six months UDVA. Aim of Study: The aim of lasik surery is emmetropia. Post lasik residual errors are necessitating redo surgery. In redo surgery many factors like corneal biomechanics, stromal bed thickness and the previous corneal flap should be considered. Different surgical techniques developed aiming at restoring emmetropia. Patients and Methods: Patients are divided into two groups each group is 40 eyes. Each group was evaluated and examined for CCT, Preoperative UDVA & CDVA, postoperative UDVA, pentacam, and all preoperative investigations. The Visumax femtosecond and MEL 90 excimer lasers were used for all FS-LASIK procedures and the MEL 90 excimer laser used for the two step trans epithelial PRK. The follow-up period were six months for both groups. Results: In both groups twenty seven patients were oper-ated for forty eyes. In group one the main SER was –1.98 ±0.47D, the main UDVA was 0.34±0.13 Log MAR, the main preoperative CDVA was 0.01±0.03 Log MAR, the main preoperative CCT was 466.10±12.08 micron, the main post-operative CCT was 309.40±9.63 micron. In group two the main SER was –1.77±0.67D, the main UDVA was 0.32±0.11 Log MAR, the main preoperative CDVA was 0.00±0.01 Log MAR, the main preoperative CCT was 402.97±20.15 micron and the main postoperative CCT was 379.27±26.26 micron. Conclusion: Both groups achieved high percentages of the postoperative target refraction with high safety and efficacy. Wave front guided ablation improves the outcome of refraction and aberrations especially in TPRK.