Secondary in-the-bag intraocular lens implantation in children who have been aphakic since early infancy

Reopening the capsular bag by removing the capsular proliferative membrane to enable secondary in-the-bag intraocular lens implantation in pediatric aphakic eyes

PURPOSE

To present a surgical technique for reopening the capsular bag in pediatric aphakia.

SETTING

Zhongshan Ophthalmic Center, Guangzhou, China.

DESIGN

Case series study.

METHODS

Consecutive pediatric patients with bilateral aphakia requiring secondary intraocular lens (IOL) implantation between July 2021 and June 2022 were included. The diameter of the capsular proliferative membranous ring (PMR) and position of IOL implantation were documented. Various parameters of capsular bag opening during primary cataract removal and secondary surgery were also analyzed.

RESULTS

48 eyes were included with a mean follow-up of 8.1 ± 4.4 months. Using the surgical technique developed in this study, the capsular bag was successfully reopened with in-the-bag (ITB) implantation in 43 eyes (89.6%). ITB implantation was accomplished in all eyes with an outer diameter of PMR ≤5.5 mm and in 3 of 8 eyes (37.5%) with an outer diameter of PMR >5.5 mm. A positive correlation was observed between the primary and secondary anterior capsular opening diameters (ACODs) ( r = 0.422, P = .007) and the primary and secondary posterior capsular opening diameters (PCODs) ( r = 0.619, P < .001). The inner diameter of PMR was found to be positively correlated with secondary PCOD ( r = 0.728, P < .001) and the outer diameter with secondary ACOD ( r = 0.669, P < .001).

CONCLUSIONS

This was a safe and effective surgical technique for pediatric secondary IOL implantation with maximum preservation of the peripheral capsule. Aphakic eyes with an outer diameter of PMR ≤5.5 mm are preferred for secondary ITB implantation.

Comparison of Aphakic Refraction and Biometry-Based Formulae for Secondary In-The-Bag and Sulcus-Implanted Intraocular Lens Power Estimation in Children

PURPOSE

The aim of the study was to compare the accuracy of refractive outcomes in children undergoing secondary in-the-bag or cilliary sulcus intraocular lens (IOL) implantation, using aphakic refraction (AR)-based formulae (Hug and Khan) and biometry-based formulae (Holladay 1, Hoffer Q, SRK/T, and SRK II).

METHODS

In this retrospective study, a total of 65 eyes of 44 patients who underwent secondary in-the-bag or cilliary sulcus IOL implantation were included and divided into 2 groups: 39 eyes of the in-the-bag IOL group and the other 26 eyes of the sulcus-implanted IOL group. Holladay 1, Hoffer Q, SRK/T, and SRK II formulae were employed depending on the biometric data, while Hug and Khan formulae were used based on preoperative AR. The prediction error (PE) and the absolute value of predicted error (APE) were compared between the 2 groups and formulae.

RESULTS

In the in-the-bag IOL group, nonsignificant differences of APE were found among the 6 formulae, while the Holladay 1, Hoffer Q, SRK/T, and SRK II all demonstrated a significant hyperopic shift of median PE value compared to the Hug formula (p < 0.05, all), and Holladay 1 and SRK II also showed a significant hyperopic shift of PE compared to the Khan formula (p < 0.05, both). Higher percentages of eyes with PE <1 D were found using Hoffer Q and SRK/T. In the sulcus-implanted group, the Holladay 1, Hoffer Q, and SRK/T had a significantly smaller median value of APE than the Hug and Khan formulae (p < 0.05, all), and the SRK II had a significantly smaller median value of APE than the Hug formula (p < 0.05), while Holladay 1 had the lowest value of APE. Higher percentages of eyes within PE <1 D were found using Holladay 1, Hoffer Q, and SRK/T, while the highest one was SRK/T. Significantly larger hyperopic shifts of median PE value using all the 6 formulae were found in eyes with sulcus-implanted IOL than eyes with in-the-bag implanted IOL (p < 0.05, all). In the eyes of with in-the-bag implanted IOL, the Hug and Khan formulae had significantly smaller APE values when compared with the eyes with sulcus-implanted IOL (p < 0.05, both).

CONCLUSIONS

Whether IOL was in the bag or implanted in the sulcus, almost all the formulae showed hyperopic shift, SRK/T showed the best accuracy. Biometry-based formulae were superior to AR-based formulae in accuracy of IOL power calculation, especially when IOL was implanted in the sulcus. In-the-bag IOL implantation should always be with higher priorities, especially when using AR-based formulae in IOL power calculation.