Purpose: To compare the difference in the clinical results of LASIK with a nasal and superior corneal flap locations.

Design: prospective, randomized comparative clinical study is to evaluate the different outcome parameters of Laser In Situ Keratomileusis (LASIK) with nasal and superior hinge locations was carried out from January 2018 to January 2020 .The follow up duration were preoperatively assessed as well as 1 week and 1,3,6 months postoperatively.

Patients and methods: This study included 1200 eyes of patients(400 female and 200 male), the eyes were randomly assigned to have a nasal or superior hinge flap with 600 eyes in each group. All patients underwent LASIK surgery for correction of myopia and myopic astigmatism using MEL 90 Excimer laser for stromal ablation, Moria M2, SBK microkeratomes were used to create superior and nasal hinged flap. Uncorrected visual acuity (UCVA), Best corrected visual acuity(BCVA) and spherical equivalent (SE) were compared before surgery and 1 week ,1,3 and 6 months after surgery.

Results: The two groups had been compared regarding the achieved improvement in the UCVA, BCVA, spherical equivalent. There was significant statistical association where P values of paired t test for all of the compared pairs below 0.001, but there is no correlated difference for pre and post-operative in different occasions regarding the best corrected visual acuity, under corrected visual acuity and spherical equivalent, so there is no statistically significant results were found in the most of the compared groups. Conclusion: This study compared efficacy, predictability and safety between both groups. The mean UCVA and BSCVA were significantly improved and the mean spherical equivalent was significantly reduced. There were no differences in efficacy, predictability and safety between nasal and superior hinge Flap.