The incidence of ocular complications during and after femtosecond-LASIK surgery for treatment of refractive errors

Abstract

The advent of refractive surgery has offered solutions for patients interested in decreasing dependence on glasses and contact lenses. Since the introduction of excimer lasers for refractive surgery, several million people have been successfully treated to decrease or eliminate their dependency on glasses or contact lenses to correct their vision due to their functional limitation. As Laser in situ keratomileusis (LASIK) either using mechanical microkeratome or FS laser is not complications free, many studies are done to rate and evaluate these complications. 100 eyes of 52 patients were included in this study, who had myopic astigmatism, compound myopic, hyperopic astigmatism, compound hyperopic and mixed astigmatism and underwent Femto-lASIK correction.they have been subjected to preoperative assessment (refraction, slit-lamp examination, fundus examination, and pentacam tomography) and then followed up post-operatively for 6 months which was arranged as multiple visits (1st, 3rd and 7th day, then at 3 weeks, 3 months and 6 months postoperatively). • The most frequent intraoperative complication was opaque bubble layer (30 eyes = 30%). • The incidence rate of other intraoperative complications was as follow: - Vertical gas breakthrough (6 eyes = 6%). - Air bubble in anterior chamber (6 eyes = 6%). - Epithelial defect (4 eyes = 4%) - Suction loss (3 eyes = 3%). - No reports of decentered flaps or flap tears. • The most frequent post-operative complication was the need for enhancement for residual refractive errors (12 eyes = 12%) • The incidence rate of other post- operative complications was as follow: - Diffuse lamellar keratitis (4 eyes = 4%). - No report of displaced flap, infection and ectasia. - No worsening of the preoperative BCVA was seen in all patients. • Post-operative refraction, UCVA, BCVA and the need for enhancement are recorded 3 months postoperatively. • Significant difference was found between pre and post-operative refraction , pre and post-operative UCVA, and pre and post-operative BCVA with p-value <0.001 for each of them. • Significant correlation was found between age and preoperative SE refraction (p-value < 0.001). • Significant correlation was found between age and Preoperative UCVA (p-value = 0.006). • This study is not without limitations, primarily the sample size; we believe a bigger sample size would have shown more precise results. Another limitation is the short follow up period, as this did not allow us to report on the incidence of ectasia. • We recommend for further multicenter studies with a larger sample size and a longer follow up period, and we recommend the use of FS laser in flap creation whenever possible due to its advantages mentioned above and the fewer rates of complications.