German researchers have found that visual performance — specifically reading speed — with multifocal intraocular lenses after cataract surgery improves with time, suggesting the brain adapts to multifocal IOLs as time goes by.
“When analyzing multifocal lens performance, it is important to follow patients over time and to remember that there is a brain behind the eyes,” said Manfred R. Tetz, MD, of the University of Berlin at the 2009 annual meeting of the American Society of Cataract and Refractive Surgery held recently in San Francisco.
Dr. Tetz and colleagues evaluated the visual performance of 25 patients who had one of two brands of multifocal IOLs (Tecnis Multifocal IOL, Abbott Medical Optics; AcrySof ReSTOR, Alcon Laboratories) implanted bilaterally after cataract removal. All patients were examined for a period of six to 18 months after surgery.
Both multifocal IOLs provided good uncorrected visual acuity (UCVA) at all distances. Mean UCVA at intermediate (arm’s length) was approximately 20/40 for both groups.
When evaluating reading speed as a measure of visual performance, the researchers found that the patients were capable of significantly faster reading speeds than patients who received bilateral multifocal IOL implants and were followed for only three months.
“This indicates there is a neural adaptation by the patient over time,” said Dr. Tetz.
Although reading speed for both groups slowed with smaller font sizes, patients in the AcrySof ReSTOR multifocal IOL group could read small fonts faster than those in the Tecnis Multifocal IOL group.
Source: Faster reading speeds over time indicates brain adapts to multifocal IOLs. Ophthalmology Times. Meeting E-News, April 4, 2009.
Tags: Cataract Surgery, multifocal IOLs