Posterior Keratometry Values May Improve M-LVC IOL Power Calculation Performance

In eyes that need cataract surgery and have had previous myopic laser surgery vision correction (M-LVC), newer IOL power calculation formulas with posterior keratometry values may provide more accurate information than older formulas.

Study Design

This retrospective cohort study included 576 eyes that had previous M-LVC and subsequently underwent cataract surgery between 2019 and 2023. Included eyes had post–cataract surgery best-corrected distance visual acuity of ≥20/30. Testing was used to evaluate the relative performance of 11 no-history post–M-LVC IOL power calculation formulas: 2 legacy M-LVC formulas (Shammas PL and Haigis-L) and 9 new M-LVC formulas, 4 without posterior keratometry values and 5 with posterior keratometry values.

Outcomes

The new M-LVC formulas were found to have better performance in calculating IOL power than the legacy M-LVC formulas, with the top-performing M-LVC formulas (EVO 2.0-PK, Pearl DGS-PK, and Barrett Tru K-TK) coming from the posterior keratometry values group. Among formulas utilizing K alone, the EVO 2.0-K and Pearl DGS-K performed best.

Limitations

Numerous IOL platforms were used with no standardized surgical technique. In addition, corneal power measurements from tomography devices, which could improve the performance of certain formulas, were not taken.

Clinical Significance

When presented with a patient with previous M-LVC, it is important to understand the limitations of older lens formulas. Using the new M-LVC formulas should be able to yield more accurate refractive outcomes, and entering posterior keratometry values may improve the formulas’ performance even more.

Financial Disclosures: Dr. Sara Bozorg discloses no financial relationships.