Corneal power measurement with a rotating Scheimpflug imaging system after Descemet-stripping automated endothelial keratoplasty

PURPOSE: To evaluate alterations in corneal power parameters after Descemet-stripping automated endothelial keratoplasty (DSAEK) using rotating Scheimpflug imaging. SETTING: University of Texas, Southwestern Medical Center, Dallas, Texas, USA. METHODS: Eyes that had DSAEK were evaluated with a rotating Scheimpflug imaging system (Pentacam). The outcome parameters were mean anterior and posterior keratometry (K), mean anterior radius of curvature and posterior radius of curvature, anterior and posterior astigmatism, central corneal thickness (CCT), true net power, corneal volume, keratometric power deviation, and mean zonal-equivalent K readings. These values were compared with those in a control group of age and sex-matched normal eyes. RESULTS: The DSAEK group comprised 32 eyes (28 patients) and the control group, 32 eyes. The mean anterior K, posterior K, and true net power were 42.53 diopters (D) +/- 1.52 (SD), -6.80 +/- 0.55 D, and 40.55 +/- 1.79 D, respectively, in the DSAEK group and 43.60 +/- 1.62 D, -6.20 +/- 0.31 D, and 42.49 +/- 1.57 D, respectively, in the control group. The posterior radius of curvature, anterior and posterior K values, and true net power were statistically significantly lower in DSAEK eyes than in control eyes (P<.01). The equivalent K readings were significantly lower in all zones in DSAEK eyes than in control eyes (P<.01). The mean CCT was significantly higher in DSAEK eyes than in control eyes (628 +/- 46 mu m versus 553 +/- 35 mu m) (P<.01). CONCLUSION: The true net power of the cornea decreased significantly after DSAEK, mainly because of an increase in posterior curvature.