The impact of cataract progression on accuracy of intraocular lens power measurement

Abstract

Purpose The aim of this study was to assess the impact of cataract progression using the Haigis formula-calculated intraocular lens (IOL) power and investigate the accuracy of IOL power measured at different time points. Methods This prospective study was performed on 75 eyes of 75 patients who underwent uneventful cataract surgery. Preoperative ocular parameters including axial length (AL), keratometry (K), anterior chamber depth (ACD), corneal astigmatism, corrected distance visual acuity (CDVA) and uncorrected distance visual acuity (UDVA) examined at the two time points, more than 3 months preoperatively and preoperative 1 day were compared. The ocular parameters measured in the two time points were used to calculate the predicted implanted IOL power and the actual IOL power was chosen on the basis of parameters measured earlier before surgery using the Haigis formula. The mean numerical error (MNE) and mean absolute error (MAE) predicted by the two time points were also compared. Results There were significant differences in the ACD, IOL power, UDVA and CDVA (P<0.01), but no statistical differences in AL, mean K and corneal astigmatism (P>0.05) during the average of 5.6 months before surgery. No statistically significant difference was detected in MNE (P>0.05), while the MAE had a significant difference in the two time points (P<0.05). Conclusion The IOL power measured earlier before surgery might result in a higher accuracy and the postoperative refractive outcome tended towards emmetropia.

Accuracy of Different Lens Power Calculation Formulas in Patients With Mature Cataracts

“…They found no difference between K and AL evaluations between the two measurements in biometry measurements performed at least three months before and one day before the surgery. However, they found a significant difference between ACD and IOL power [16]. In addition, in this case, two measurements were statistically significant in terms of MAE.…”

A Comparative Study of Two Extended Depth of Focus Intraocular Lenses

“…11 The MNE and mean absolute error (MAE) defined as the arithmetical mean of prediction errors and the mean of the magnitude of prediction errors, respectively. 12 The MAE is useful in estimating the accuracy of IOL power calculations. 13 Defocus curves were obtained monocularly using defocusing lenses with a power range of 1.50 diopters (D) to 24.00 D at all 0.5 D steps.…”