Central thickness variation in precut DSAEK donor grafts

摘要

Cataract extraction and intraocular lens (IOL) implantation are often staged before Descemet-stripping automated endothelial keratoplasty (DSAEK) or performed as a combined procedure, so it is important to factor the expected refractive shift from the DSAEK procedure into the IOL calculation. Currently, the range of spherical equivalent shift after DSAEK is 4.0 to 5.0 diopters (D), which limits the accuracy of the IOL calculation.In the recent analysis by Dupps et al., most (86%) of the variation in refractive shift after DSAEK could be explained by 2 factors: central graft thickness and a curvature coefficient calculated from the graft thickness profile from center to periphery. The analysis was limited to 7 grafts with central graft thicknesses of 144 to 221 mum. This thickness range was estimated to have a 3.7 D range of refractive influence, with thicker grafts associated with more hyperopic shift.