Babies who receive intraocular lenses after surgery for congenital unilateral cataract have more post-operative complications than those who use contact lenses post surgery, a study shows.
Although no significant differences in visual acuity were found between the two groups at age one or 4.5 years, significantly more postoperative complications existed in the IOL group, which led to more corrective surgeries.
The study, published online on 6 March in JAMA Ophthalmology, enrolled 114 infants aged from one month to six months at the time of surgery. About half were randomised to IOL and the other half to contact lenses for small eyes.
Evaluations at one year and 4.5 years of age found the most frequent complication was lens proliferation and by age five years, lens proliferation was 10 times more common with IOLs, occurring in 23 infants (40 per cent), compared with two infants (four per cent) in the contact lens group.
Despite challenges with contact lens use including potential discomfort and anxiety for parents in daily lens maintenance and affordability, researchers believed contact lenses were a better option for most infants than IOLs.
Brisbane optometrist David Foresto who fits contact lenses for babies after surgery for congenital cataract and eye trauma said this was the most comprehensive study on paediatric aphakia and proved to policy makers that optometrists were critical in the management of paediatric aphakia.
‘The Infant Aphakia Treatment Study has confirmed what we suspected, that contact lenses are a safer and more cost-effective treatment than infantile IOLs for unilateral paediatric aphakes,’ he said.
‘One interesting finding was that overall parental stress in the contact lens wearing group was no higher than in the IOL group. This seems to be due to higher complication rates in the IOL group than in the contact lens group.’
Adelaide optometrist and head of contact lenses teaching at Flinders University Department of Optometry and Vision Science, Associate Professor Tony Phillips, fits contact lenses to babies post surgery. He said the original paper stated that IOLs were not as accurate optically as contact lenses because optometrists could easily modify the power in a contact lens to keep it correct to enable the eye to focus to where babies normally look.
Tony Phillips checks the fit of a contact lens
‘In the first year of life, we focus the baby’s eye purely for close, in the second year we focus the eye a little further away and during the third year, we take the focus to infinity and give the child reading spectacles,’ he said.
‘With IOLs, only 42 per cent of the predicted powers were correct to within 1 D or less with an average prediction error of 1.8 D, that is, some were obviously considerably out.
‘When you put an IOL in a newborn you have to predict—guess!—what the correct power will be when they grow up. At the Adelaide Women’s and Children’s Hospital we put just about everyone into a contact lens if they are born with cataract or persistent hyperplastic primary vitreous.
‘Mostly surgeons wait until the child is about six before doing an implant; earlier if there are contact lens problems.’
Lambert SR et al for the Infant Aphakia Treatment Study Group. A comparison of contact lens and intraocular correction for monocular aphakia during infancy: a randomized clinical trial of HOTV optotype acuity at age 4.5 years and clinical findings at age 5 years. JAMA Ophthalmology, online 6 March 2014.