CONGENITAL CATARACTS

M Edward Wilson, MD

The role of primary intraocular lens (IOL) implantation when operating on congenital cataracts in infants less than six months of age has been controversial. Speaking in Barcelona, Spain, at a joint symposium of the 3rd World Congress of Paediatric Ophthalmology and Strabismus and the XXXIII Congress of the ESCRS, M Edward Wilson MD said the decision should be individualised and evidence-based as much as possible.

The only Level I evidence on this issue supports leaving a baby aphakic if the surgeon believes that the family will likely be successful with contact lens correction, said Dr Wilson, Professor of Ophthalmology and Paediatrics, Storm Eye Institute, Medical University of South Carolina, Charleston, USA.

He reviewed the findings from the Infant Aphakia Treatment Study (IATS), the only multicentre, randomised controlled trial evaluating outcomes of infants undergoing cataract surgery with and without IOL implantation.

Contrary to the investigators’ expectations, analyses of data from follow-up when children were ages one and 4.5 years showed no difference in median visual acuity between the group that underwent primary IOL implantation and children receiving a contact lens to correct aphakia. Findings of the safety review, however, showed rates of complications, adverse events, and additional intraocular surgeries were higher in the primary IOL implantation group.

POTENTIAL RISKS

The IATS also found fewer returns to the operating room during the first year of life in the aphakic group, which is important considering the potential risks of repeated general anaesthesia during this critical period of neurodevelopment. In addition, cataract surgery is faster and less traumatic to the eye if the child is left aphakic, and children using contact lenses for correction do not need to wear glasses, said Dr Wilson.

“Furthermore, contact lens correction gives maximum flexibility to adapt for the rapid and unpredictable changes in axial length and refractive error occurring during infancy. I think it is better to choose IOL power at age five or six, at the time of secondary implantation, than when the child is just six weeks of age,” he told delegates.

Dr Wilson also pointed out that the circumstances of a particular case may influence the surgeon’s decision about IOL implantation. Such factors would include the complexity of the case or if the eye is very microphthalmic.

“Not all infant cataracts are alike, and there is not one best treatment for every case. In addition, participants in multicentre clinical trials must fit certain criteria, and so the evidence may not apply to every patient you see,” he added.

M Edward Wilson: wilsonme@musc.edu