Incidence of Posterior Vitreous Detachment After Femtosecond LASIK Compared With Microkeratome LASIK

PURPOSE:To compare the incidence of posterior vitreous detachment (PVD) after femtosecond and microkeratome laser in situ keratomileusis (LASIK). SETTING:Rowad Correction Centre, Cairo, Egypt (a private center affiliated to Cairo University). DESIGN:Prospective, nonrandomized comparative unmasked study. METHODS:The study was conducted at a single laser center. Eligible patients chose between femtosecond and microkeratome LASIK after appropriate counseling. B-scan ultrasonography was performed before surgery by a single operator. Patients with preexisting PVD (partial or complete) were excluded. The axial length was also recorded. All surgery was performed by a single surgeon. During surgery, the suction time was measured. Ultrasonography was repeated 1 month after surgery by the same operator to detect PVD. RESULTS:Ten patients (20 eyes, group M) underwent LASIK using the Moria M2 microkeratome, and 10 patients (20 eyes, group F) underwent femtosecond LASIK with the IntraLase FS-150. In groups M and F, respectively, the proportion of women was 80% and 70%, and the mean age was 24.7 ± 4 years and 25.7 ± 3.3 years, the mean axial length was 24.2 ± 1.2 and 23.8 ± 1.2 mm, and the mean suction time was 18 ± 2 seconds and 63 ± 4 seconds (P < 0.001). After surgery, PVD was detected in 4 eyes (20%) in group M and 17 eyes (85%) in group F (P = 0.000044). CONCLUSIONS:The incidence of PVD 1 month after femtosecond LASIK was higher than after microkeratome LASIK. This may be due to longer suction time during femtosecond LASIK despite lower suction pressure.