Reliable ray tracing for calculating IOL power

July 23, 2012

Ray tracing with patient-customized eye models is effective in calculating IOL power, claims a recent case series study.

Using ray tracing with patient-customized eye models is an effective procedure in calculating IOL power, claims a case series study in the Journal of Cataract and Refractive Surgery.

Dr Carmen Canovas et al., Hospital Universitario Virgen de la Arrixaca, Murcia, Spain, calculated optimum IOL power using ray tracing with a patient-customized eye model in those requiring cataract surgery. There were 18 non-LASIK patients and 10 LASIK patients included in the study. The results for IOL power predictions were compared with the optimum postoperative IOL power.

The standard approach to IOL calculation and the ray-tracing technique gave similar mean absolute residual error and variance in non-LASIK patients. In all LASIK patients the ray-tracing procedure was the most accurate.

Differences between the prediction of IOL power with corneal aberrations and without was linked to the amount of corneal spherical aberration. In some cases this resulted in a difference of up to 3.00 D in IOL power.

Ray tracing using patient-customized eye models was found to be a strongly successful tool for IOL power calculation. But corneal aberrations must be incorporated in post-LASIK eyes due to increased corneal spherical aberration.

The full abstract can be found in the Journal of Cataract and Refractive Surgery, click here