The IOLAB, Inc pediatric intraocular lens study. AAPOS Reasearch Committee. American Association for Pediatric Ophthalmology and Strabismus.

PURPOSE

This report is a summary of the data of the IOLAB, Inc pediatric intraocular lens (IOL) implantation investigation. The goal of this study was to evaluate the safety and efficacy of IOL implantation for the treatment of pediatric aphakia, pending approval by the Food and Drug Administration.

METHODS

From May 1981 to July 1994, a total of 1260 pediatric eyes received 171 styles of IOLs implanted by 361 US investigators. Preoperative, operative, and postoperative status reports over the first year were required for each eye entered into the study. Annual visit reports were requested thereafter to determine the long-term effects. The study was terminated in November 1995. All IOLs were obtained from IOLAB, Inc (now Chiron Vision Corp).

RESULTS

Reporting compliance was 98.3% for the preoperative and operative reports, 45.1% at 1 year, and 13.8% at 3 years. The subjects' ages ranged from younger than 1 yearto 17 years. Nine subjects (0.7%) were younger than 1 year, with the largest group of 533 subjects (42.3%) aged between 6 and 12 years atthe time of surgery. Cataract types were congenital (45.6%), traumatic (37.1%), secondary (11%), senile (0.95%), and unrecorded (5.4%). The IOL was implanted primarily in 74.8% of cases and secondarily in 21.4% of cases. There was no record in 3.8% of the cases. IOL types included anterior chamber (4.1%), iridocapsular (0.71%), posterior chamber (93.6%), and unrecorded (1.59%). There were 130 adverse reactions that required secondary surgical intervention. The most frequently performed surgical procedures included lens removal without replacement, vitrectomy, lens repositioning, and lens replacement. More than half (52%) of all eyes had a visual acuity of 20/200 or worse before surgery; amblyopia was reported in 21.1% of all participants at baseline. Postoperative visual acuity data were available on 563 eyes at 1 year after surgery. Overall, 52.8% of all eyes attained a visual acuity of 20/40 or better by the 1-year visit, and only 15.5% had visual acuity worse than 20/200. In general, the older patient, traumatic cataract, and secondary cataract categories were overrepresented in the better visual acuity outcome group.

CONCLUSION

The IOLAB, Inc pediatric IOL study is the first multiple-practitioner, national study designed to evaluate the safety and efficacy of IOL implantation in children. The study results are compromised by the almost 50% loss of follow-up at the 1-year evaluation. Other variables that most likely influenced outcome results were the methods of cataract extraction, medical management, and IOL design, all of which evolved dramatically over the time course of the study. Despite these issues, pediatric IOL implantation seems to be a reasonable treatment modality for aphakia, on the basis of the available 1-year follow-up data of the remaining 45.1% of eyes in the study.