Accuracy of IOL calculations in children: a comparison of immersion versus contact A-scan biometery

Abstract

Purpose: To evaluate the accuracy of pediatric IOL calculations performed under general anesthesia by using immersion A-scan biometry and to compare the results to those obtained using contact A-scan biometry.

Methods: A retrospective review of 203 consecutive cases of pediatric cataract extraction with primary IOL implantation within the capsular bag; mean patient age was 5.52 +/- 4.19 years (range, 18 days to 18 years). Axial length measurements were performed with the contact A-scan biometry in 138 eyes, whereas immersion technique biometry was used in the remaining consecutive 65 eyes. Preoperative predictive target refraction was compared with the refractive result obtained at the 2-month postoperative visit.

Results: The mean of the absolute value lens prediction error for all eyes was 1.08 +/- 0.93 D from the desired postoperative refractive result. Lens prediction error for the contact A-scan subgroup was 1.11 +/- 0.90 D, whereas the immersion A-scan subgroup was less at 1.03 +/- 0.98 D. This result was not statistically significant (p = 0.6442). Statistically significant correlations were found between increased lens prediction error and age at time of surgery or corneal curvature.

Conclusions: This retrospective, noncomparative pilot study showed no significant difference in IOL prediction error when comparing the postoperative refractive results obtained with immersion versus contact A-scan biometry in pediatric IOL calculations.