Purpose: To evaluate the precision of bag-in-the-lens intraocular lens (BIL IOL) power calculation in different age groups of pediatric cataract patients.

Settings: Department of Ophthalmology, Justus-Liebig-University Giessen, University Hospital Giessen and Marburg GmbH, Campus Giessen, Giessen, Germany.

Design: Retrospective nonrandomized consecutive case series.

Methods: Pediatric patients diagnosed with cataract and operated with BIL IOL implantation were divided into 4 age groups: Group 1 (0 to 3 months), Group 2 (>3 months, <12 months), Group 3 (12 to 36 months), and Group 4 (>36 months to 17 years). BIL IOL power was calculated with the SRK/T formula. The prediction error (PE) was defined as the absolute difference between the preoperative selected target and postoperative achieved refraction. The impact of age at the time of surgery, axial length (AL), keratometry, and corneal astigmatism on PE was analyzed.

Results: The study comprised 87 eyes of 56 pediatric patients. The mean and median PEs for the entire group were 1.79 diopters (D) and 1.23 D, respectively. The mean PE in each age group was: 3.43 D in Group 1, 2.14 Din Group 2, 1.60 Din Group 3, and 1.33 D in Group 4. The mean PE in eyes with ALs shorter than 20 mm was 2.67 D, and 1.44 D in eyes with an AL of 20 mm or longer. The mean PE in eyes with corneal radii less than 7.3 mm was 2.45 D, and 1.66 D in eyes with corneal radii of 7.3 mm or more. In the age and AL subgroups, the PE differences were statistically significant (P < .05).

Conclusions: The PE was larger in the youngest study group, and it decreased gradually with age and in eyes with ALs shorter than 20 mm. The PE has to be considered during BIL IOL power calculation in children. (C) 2019 ASCRS and ESCRS