Accuracy of measuring the diopter power of intraocular lenses after hemidissection.

PURPOSE: To assess whether the power of intraocular lenses (IOLs) can still be accurately measured after hemidissection, by comparing the measurements of intact lenses with those of the hemidissected lenses.

SETTING

University tertiary referral hospital.

DESIGN

Laboratory study.

METHODS

Monofocal (n = 8), extended depth-of-focus (EDOF) (n = 2), and trifocal IOLs (n = 2) from leading manufacturers were evaluated. The power of each IOL was assessed in the intact state and after hemidissection under room temperature conditions. Subsequently, optical evaluation was performed with a single half (the larger part) placed in a model eye, and then with both halves reassembled, aligning the adjacent edges along the hemidissection line. A 1-way analysis of variance was used to compare repeated measures across these conditions.

RESULTS

On evaluating the powers of the IOLs, no statistically significant differences were observed among the intact, one-half, and two-halves conditions ( P = .77). Most of the post-hemidissection power measurements fell within the ±0.4D tolerance range. On average, the differences in power before and after hemidissection were minimal, measuring approximately 0.15 ± 0.17 diopters (D) for monofocal, 0.10 ± 0.07 D for EDOF, and 0.02 ± 0.01 D for trifocal IOLs.

CONCLUSIONS

The power of a hemidissected IOL can be accurately assessed. Measuring one-half of a hemidissected IOL provides results that are comparable with those from evaluating both halves, thus accurately reflecting the power of the intact ones. This study suggests that confirming a deviation in power of an explanted lens is a viable option despite the physical damage caused by explantation procedures.