Secondary in-the-bag intraocular lens (IOL) implantation achieved a lower incidence of adverse events than ciliary-sulcus secondary IOL implantation, according to an American Journal of Ophthalmology study. The research also shows enhanced IOL centration and better-corrected visual acuity (BCVA) for pediatric aphakia with the in-the-bag approach.
The incidence of adverse events following IOL implantation at 12 to 60 months in pediatric aphakia patients is between 19.5% and 28.5%, the study says. These events could impact the pediatric patients’ long-term visual functioning, according to investigators.
The research included 355 aphakic eyes of 202 children who were diagnosed with congenital cataracts and who underwent cataract extraction before 24 months of age. Eyes received in-the-bag or ciliary sulcus secondary IOL implantation determined by the quantity of residual lens capsule and were followed for 3 years after surgery.
In total, 40.6% of eyes received in-the-bag IOL implantation (the capsular group), with the remaining undergoing ciliary sulcus IOL implantation (the sulcus group). The investigators found that the time-dependent incidence of glaucoma-related adverse events (GRAEs) (P =.005) and all other adverse events (P =.002) were increased in the sulcus group. This shows that in-the-bag IOL implantation protects strongly against GRAEs and AEs, according to the report. The sulcus group was more prone to experiencing clinically significant IOL decentration (>0.4 mm) compared with the capsular group.
Although secondary in-the-bag IOL implantation results in improved prognosis in children, the method used during secondary IOL implantation depends on intraoperative factors in cataract extraction, according to investigators. Scarring and destruction of the lens capsule are the major challenges. The peripheral lens capsule must be protected during cataract extraction to accomplish secondary in-the-bag IOL implantation.
“Our previous work and that of other researchers suggests that the anterior capsulorhexis diameter should be 4-5 mm and the posterior capsulorhexis 3.5-4 mm during cataract extraction, in order to avoid damaging the lens epithelial cells and to promote formation of a transparent and volumized Soemmerring ring, which is conducive to secondary in-the-bag IOL implantation,” researchers report.
Strengths of the current study include it likely being the largest to examine longitudinal outcomes of in-the-bag compared with ciliary sulcus secondary IOL implantation in pediatric eyes. Another strength is that the investigators used regression modeling to limit potential confounders including preoperative visual acuity, age at cataract extraction/IOL implantation, and length of operative interval.
Limitations of the current study include a paucity of inter-group differences before IOL implantations, including preoperative BCVA, age at cataract extraction/IOL implantation, surgical interval, axial length, and intraocular pressure. With regard to methods of visual acuity assessment, differing ages of participants could have impacted comparability of vision data.
Liu Z, Lin H, Jin G, et al. In-the-bag versus Ciliary Sulcus Secondary Intraocular LensImplantation for Pediatric Aphakia: A Prospective Comparative Study. Am J Ophthalmol. Published online October 12, 2021. doi:10.1016/j.ajo.2021.10.006