Retreatment of myopic LASIK with femtosecond and custom ablation
Reviewed by Mrinal Rana

The purpose of this study was to identify the risk factors for retreatment post laser in situ keratomileusis (LASIK). A retrospective chart review was carried out for a four-year period and all patients who had undergone LASIK at the Boston Eye group were identified and data was collected. A total of 2581 patients underwent wavefront-guided procedure utilising femtosecond technology. Of these only 83 underwent retreatment (3.2%). Demographic and refractive data was collected. The primary outcome measures were aimed at addressing the potential risk factors leading to the increase in the incidence of retreatment post LASIK treatment or in myopic regression. The factors looked into were age, gender, initial preoperative manifest refraction spherical equivalent (MRSE) measured in diopters (D), total astigmatism and iris registration capture. The analysis showed that there was an increase in the regression in age more than 40 years (p<0.001), initial MRSE >-3.0D (p=0.02) and astigmatism >1.0D (p=0.001). Iris registration capture did not have significant effect on the reduction of the retreatment rates. This new data improves upon the existing knowledge of risk factors for re-treatment post femtosecond LASIK compared to previous studies, which have looked at similar risk factors using the manual microkeratome flap-creating mode. The improved understanding of these risk factors can be used to set realistic goals during the preoperative evaluation and bolster greater patient understanding should the need for retreatment arise. 

Risk factors for retreatment following myopic LASIK with femtosecond laser and custom ablation for treatment of myopia.
Kruh JN, Garrett KA, Huntington B, et al.
SEMINARS IN OPHTHALMOLOGY
2017;32(3):316-20.