Discrepancies between intraocular lens implant power prediction formulas in pediatric patients

The SRK II, SRK/T, Holladay I, and Hoffer Q intraocular lens power prediction formulas have been claimed to be interchangeable in their predicted postoperative refractive outcome among pediatric patients. In this study, we evaluated this clinical perception.

Mathematical analysis.

Analytical prediction of implant power using keratometry values up to 55 diopters and axial length values as short as 16 mm was performed for 2 different refractive goals using the optimized intraocular lens constants for the SRK II, SRK/T, Holladay I, Hoffer Q, and Haigis formulas. Comparison graphs for the predicted implant power of each formula were constructed and differences between predicted results of the formulas were plotted.

Predicted implant power.

Significant differences in intraocular lens power prediction were found among the Hoffer Q, Holladay I, and SRK II formulas in the pediatric range of axial length and keratometry values. The Holladay I and Haigis formulas were found to be similar in their intraocular lens power prediction. The SRK/T was comparable with the Holladay I and Haigis formulas, but still differed in the high keratometry values.

This analysis demonstrates differences in the intraocular lens power prediction among commonly used formulas for axial length and keratometry values in the pediatric range. It is unclear under what circumstances each of these formulas may be preferred in the pediatric population.