Accuracy of new-generation intraocular lens formulas in IOL power calculation for cataract extraction combined with vitrectomy.

PURPOSE: To evaluate the accuracy of new-generation intraocular lens (IOL) power formulas in patients undergoing combined cataract extraction and vitrectomy (phacovitrectomy).

METHODS

We retrospectively collected the clinical data of patients who underwent phacovitrectomy at the First Affiliated Hospital of Army Medical University between January 2015 and December 2022. IOL power was assessed with Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO), Kane, Haigis, Hoffer Q, Holladay 1, and SRK/T formulas. Outcomes included mean prediction error (ME), mean absolute error (MAE), median absolute error (MedAE), and percentages within ± 0.25 to ± 1.00 D. Subgroup analyses were performed by axial length (AL), diagnosis, and tamponade agent.

RESULTS

A total of 138 eyes were analyzed: 79 epiretinal membrane (ERM), 38 macular hole (MH), and 21 primary rhegmatogenous retinal detachment (RRD). Between-formula differences were significant overall (P < 0.01). BUII and EVO achieved significantly lower MedAEs (0.36 D and 0.32 D) than Hoffer Q and Holladay 1 (0.51 D and 0.57 D). BUII, EVO, and Kane achieved higher percentages of eyes within target error thresholds than SRK/T, Hoffer Q, and Holladay 1 (all P < 0.01). BUII and Haigis were relatively stable across AL subgroups, whereas SRK/T, Hoffer Q, and Holladay 1 exhibited larger MedAE values in eyes with AL ≥ 30 mm. All formulas performed worse in RRD, and MedAEs were also larger in silicone-oil eyes.

CONCLUSION

In ERM or MH phacovitrectomy, new-generation formulas, particularly BUII and EVO, provide more accurate refractive prediction than traditional formulas. In RRD and silicone-oil cases, refractive uncertainty remains substantial.