Abstract
Purpose
This study aimed at comparing femto-LASIK with small incision lenticule extraction (SMILE) as regards the safety, efficacy, accuracy and post-operative complications with special emphasis on the post-operative dry eye, corneal sensation and corneal biomechanics in cases of myopia and myopic astigmatism.
Patients and Methods
The study was a prospective comparative study that was conducted in a private eye hospital on 60 eyes of 30 patients with myopia or myopic astimgatism. Each patient was fully assessed preoperatively including visual acuity, refraction, tear breakup time, Schirmer test, corneal sensation & Ocular Response Analyzer®. Femto-LASIK was done to 15 patients and SMILE was done to 15 patients. Postoperative visual acuity, refraction, tear breakup time, Schirmer test, corneal sensation at 1 month, 3 months and 6 months and Ocular Response Analyzer® at 6 months were done and data was retrieved and analyzed.
Results
Cylindrical error was higher in SMILE group at all postoperative points. Tear breakup time was better in SMILE group in 1st month, but no significant difference in later follow ups. Corneal sensation was better in SMILE group in 1 month and 3 months, but this difference disappeared at 6 months. Corneal hysteresis & corneal resistance factor were significantly better in SMILE group.
Conclusion
Both techniques are safe and efficient. Femto-LASIK is more efficient in correcting cylindrical error. SMILE is better in early postoperative dry eye, corneal sensation and in corneal biomechanics.
Early changes to dry eye and ocular surface after small-incision lenticule extraction for myopia