Precision In Determining Intraocular Lens Power Through Measuring Distances From Haptics To The Principal Object Plane

This study aims to evaluate how the distance from the optic's most-anterior surface to the principal object plane (POP) and from the front of the haptic to the principal object plane (H-POP) influences the calculation of intraocular lens (IOL) power.

This research includes both an optical simulation and a retrospective cross-sectional analysis. 

Using data from the ICB00 IOL configuration, the optical simulation mapped out variations in the POP and H-POP across different IOL powers. The clinical study analyzed 102 eyes from 102 patients who had received the ICB00 IOL implant. It focused on assessing the relationship between shifts in POP and H-POP distances and the prediction errors, calculated using the Barrett Universal II formula, across various IOL powers.

Changes in the POP were slight, ranging from 0.21 mm to 0.30 mm, as IOL power varied. Meanwhile, H-POP values rose incrementally starting at 5.0 D, reaching a peak of 0.60 mm at 16.0 D, before declining to a low of 0.14 mm at 34.0 D. Analysis of prediction errors mainly reflected alterations in H-POP rather than POP with different IOL powers. A linear regression analysis indicated a significant trend towards myopic errors as IOL power exceeded 16.0 D (Y = –0.069X + 1.420, R² = 0.178, p < 0.001).

The results of this study suggest that H-POP measurements play a more critical role than POP in determining IOL power for the ICB00. To enhance the accuracy of IOL power calculations, it is crucial for manufacturers to offer detailed data on both the optic and haptic geometries, facilitating precise H-POP estimations.