A Novel Role for Corneal Pachymetry in Planning Cataract Surgery by Determining Changes in Spherical Equivalent Resulting from a Previous LASIK Treatment

Figure 3

Spherical equivalent of LASIK treatments as a function of the postoperative central to semiperipheral corneal thickness (CPT) ratio. (a) The CPT ratio calculated from the precomputed values of central and semiperipheral (at 3 mm radius) corneal thicknesses provided by the Pentacam UI software and (b) the CPT ratio calculated from the extracted raw data values of central and semiperipheral (at 2.5 mm radius) corneal thicknesses provided by the .csv export function of the Pentacam software. The computed mean cutoff is shown for both panels. Using raw data increased accuracy substantially (b) with dots in the extremes (lower left and upper right quadrants) showing less spread from the ideal linear regression.

(a)

(b)