Multifocal intraocular lenses (IOLs) are a good choice for the right patient.
Multifocal intraocular lenses (IOLs) are a good choice for the right patient, according to Dr. Martin Leyland of the Royal Berkshire Hospital, presenting the third update of the Cochrane systemic review of multifocal vs. monofocal studies.
All the studies reviewed were randomized controlled trials. "I think there is a problem assessing multifocal lenses because there are two interventions. There is cataract surgery, and these patients tend to be happy with the outcome irrespective of what lens you put in. Then you put the lens in, so for any study to be valid you have to have a control group of monofocal lenses," said Dr Leyland.
Dr Leyland summarized the results 10 RCT studies and found that there was no difference in distance high contrast VA between the two types of lens, while UCVA for near vision was better with the multifocal. It was impossible to compare BCVA for near because the methodology varied so widely between studies. In each of the studies, contrast sensitivity was lower for multifocal IOLs.
"Whether the difference attained statistical sensitivity depended on the size of the study," said Dr Leyland. "But in every trial it was a small difference, much smaller than the 40 to 50%% reduction in contrast you would expect from the optics in a multifocal lens. There must be some sort of post perception processing to compensate for."
For glare and halo, monofocals were significantly better, while multifocal IOLs very significantly reduced spectacle dependence. In 34" of cases, multifocal patients did not need glasses at all.