Modified Surgical Techniques for Pediatric Cataract Treatment

Pediatric cataract is totally different from adult cataract. There is traditionally no difference in technique between pediatric and adult cataract surgery. Opacification of the visual axis was the most frequent complication after pediatric surgery. In this clinical study, the investigators aimed to evaluate the safety and postoperative recovery of a modified technique for pediatric cataract surgery.

This study is a randomized, controlled clinical trial with the following objectives: To determine whether infants with congenital cataract have improved visual outcomes following cataract extraction surgery using (1) the traditional capsulorhexis method or (2) our new minimally invasive method. To determine the occurrence of postoperative complications among infants with congenital cataract following cataract extraction surgery using (1) the traditional capsulorhexis method or (2) our new minimally invasive method. The study is conducted for the following reasons: Transplantation of pluripotent stem cells represents an appealing therapeutic strategy in regenerative medicine, but its clinical applications have been hindered in part by concerns about tumorigenicity and immune rejection. The use of endogenous stem cells provides a possible solution to this problem. Lens regeneration has been reported in lower vertebrate animals. Furthermore, residual endogenous lens epithelial stem cells (LESCs) after lens removal in rabbits have been shown to proliferate and generate lens fibers. Cataract, or opacification of the lens, is a major cause of blindness worldwide. Surgery for congenital cataract carries a significant risk of complications and often requires additional surgical procedures to maintain the transparency of the visual axis. Implantation of intraocular lenses (IOLs) following cataract extraction is becoming increasingly common in the pediatric population. However, their use is controversial in children younger than two years old (especially not recommended in children younger than 6 months old due to the high incidences of IOL-related complications), as the refractive power of the eye continues to develop. In addition, IOLs have many limitations, including dislocation, less than ideal biocompatibility, inadequate accommodative properties, and suboptimal visual outcomes. The trial will demonstrate whether a modified cataract surgical technique can regenerate the lens from endogenous stem cells. It will also compare the incidence of complications and characterize visual outcomes in pediatric patients treated with the modified surgical technique versus the traditional surgical technique.

pediatric cataract, lens regeneration, endogenous lens epithelial stem cells, visual axis opacification, visual function

In the modified cataract surgery procedure, the size of the capsulorhexis opening will be decreased to 1.0-1.5 mm in diameter. The capsulorhexis will be located in the peripheral area of the lens instead of the central area. A 0.9 mm phacoemulsification probe will be used to remove the cataractous lens. One drop of 0.5% or 1% atropine and an antibiotic/steroid ointment will be placed in the eye, which will then be patched.

• In traditional technique group, the cataractous lens will be removed through an anterior continuous curvilinear capsulorhexis (ACCC) that is about 5-6 mm in diameter.

Inclusion Criteria: Age between 1 month and 24 months Uncomplicated congenital cataract (≥ 3 mm central dense opacity) in one or both eyes with an intact non-fibrotic capsular bag Informed consent signed by a parent or legal guardian Exclusion Criteria: Intraocular pressure >21 mmHg Preterm birth (<28 weeks) Presence of other ocular diseases (keratitis, keratoleukoma, aniridia, glaucoma) or systemic disease (congenital heart disease, ischemic encephalopathy) History of ocular diseases (any congenital eye diseases, such as, congenital cataract, congenital glaucoma, congenital aniridia) in the family History of ocular trauma Microcornea Persistent hyperplastic primary vitreous Rubella Lowe syndrome

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