Early diagnosis of subclinical keratoconus by wavefront parameters using Scheimpflug, Placido and Hartmann-Shack based devices.

Corneal wavefront indices generated from different devices have acceptable validity for differentiating normal cornea from the early form of KCN, and this can be very useful for preoperative screening before refractive surgery. The front BCV with Sirius was the most accurate parameter for diagnosis of SKCN followed by Z3-1 with Pentacam and OPD-Scan III.