Accuracy of Point-Source Color LED Corneal Topographer for IOL Power Prediction in Corneas Having LASIK or PRK

Tuesday, April 21, 2015: 11:01 AM
Room 1B (San Diego Convention Center)
Sumitra Khandelwal, MD
Douglas D. Koch, MD
Li Wang, MD, PhD
Mitchell P. Weikert, MD

Purpose
To compare the accuracy of intraocular lens (IOL) power calculations using 5 devices:  1) Cassini point source color LED cornea topographer with reflective technology for measuring posterior corneal curvature (I-optics) , 2) IOLMaster (Carl Zeiss Meditec), 3) Lenstar (Haag Streit), 4) Humphrey Atlas (Carl Zeiss Meditec), and 5) Galilei dual-Scheimpflug tomographer (Ziemer).

Methods
In this prospective comparative study of cataract patients who have undergone myopic LASIK or PRK, a single observer obtained three sets of keratometric readings with each of the devices.  The IOL prediction error was calculated as the implanted IOL power minus the predicted IOL power. Arithmetic and absolute mean and median IOL prediction errors, variances in mean arithmetic IOL prediction error, and percentage of eyes within +/-0.50 diopter (D) and +/-1.00 D of refractive prediction errors are calculated.

Results
The above outcomes will be reported.

Conclusion
We will report if the color LED topographer with posterior corneal measurements improves the accuracy of IOL calculations in post-refractive surgery eyes.