Related Experiment Video
Updated: Aug 13, 2026
Rotating the Intraocular Lens to Prevent Posterior Capsular Opacification in Cataract Surgeries
Published on: July 7, 2023
Refractive Predictability of Third-Generation and Modern IOL Power Calculation Formulas in Yamane Intrascleral
Mehmet Icoz1, Burak Tanriverdi2, Mehmet Yakin2
1From the Department of Ophthalmology (M.I.), Yozgat City Hospital, Yozgat, Turkey.
Purpose:
To evaluate the refractive predictability of third-generation and modern intraocular lens (IOL) power calculation formulas in eyes undergoing Yamane intrascleral fixation (YISF).
Design:
Retrospective, comparative evaluation of IOL power calculation accuracy.
Subjects:
Eighty-seven eyes of 87 patients who underwent YISF due to aphakia or single-piece IOL subluxation were evaluated.
Methods:
Third-generation formulas (Hoffer Q, Holladay 1, Sanders Retzlaff Kraff/Theoretical (SRK/T), and T2) and modern formulas (Barrett Universal II[BUII] and emmetropia verifying optical [EVO] 2.0) were assessed.
Main Outcome Measures:
Mean prediction error (ME), mean absolute error (MAE), median absolute error (MedAE), and the proportions of eyes with ME within ±0.50D and ±1.00D were calculated. Analyses were performed before and after constant optimization. The constant optimization was performed using the method of zeroing the ME.
Results:
In the initial analysis, all formulas demonstrated a hyperopic shift, with ME values ranging from +0.55D to +0.71D. No significant differences were detected among the formulas in terms of ME, MAE, or MedAE (P > .05). The proportion of eyes with ME within ±0.50D was higher for SRK/T (63%), BUII (60%), and EVO 2.0 (54%) than for Hoffer Q (48%) (P < .001, P < .001, and P = 0.004). In contrast, no significant difference was found in the proportion of eyes with ME within ±1.00D (P > .05). After constant optimization, ME reached zero for all formulas, and no significant differences were observed among the formulas regarding MAE, MedAE, or the proportions of eyes with ME within ±0.50D and ±1.00D (P > .05). In both analyses, no statistically significant differences were found among the six formulas with respect to either IOL type or indication (P > .05).
Conclusions:
A systematic hyperopic shift was observed with all formulas after YISF. Although SRK/T, BUII, and EVO 2.0 appeared more successful before optimization, third-generation and modern formulas demonstrated similar refractive performance after constant optimization. These findings suggest that refractive outcomes are largely influenced by surgery-related variability in actual lens position.
