Multifocal IOL provides high-quality vision for patients

Chicago-The ReZoom multifocal IOL (AMO) provides excellent distance vision and useful near and intermediate vision to afford complete spectacle independence for 80% to 90% of patients with the lens implanted, said Michael C. Knorz, MD, at the Refractive Surgery Subspecialty Day Meeting sponsored by the International Society of Refractive Surgery of the American Academy of Ophthalmology.

He presented results from a series of 12 cataract surgery patients who had the ReZoom IOL implanted bilaterally, and compared their outcomes with published data for two other multifocal IOLs-the AcrySof ReSTOR (Alcon Laboratories), the new multifocal IOL featuring apodized diffractive optics technology, and the Array multifocal lens (AMO). The ReZoom IOL was built on the Array platform and like the Array has a hydrophobic acrylic optic that is distant-dominant with a 3.5-D add. However, the ReZoom features an optimized multifocal surface (Balance View Optics) with five optical zones that optimize light distribution on the retina for varying lighting conditions and pupil sizes.

Excellent distance vision

"The findings of slightly better distance vision results with the ReZoom IOL and slightly better near acuity with the ReSTOR are consistent with the fact that the ReZoom IOL has a distance-dominant optic. However, with its optimized multifocal surface, the ReZoom affords high rates of spectacle independence for all distances. In a recently reported series, 93% of patients were spectacle-independent for distance, 93% for intermediate, and 81% for near," Dr. Knorz said.

Data on higher-order aberrations were obtained using the Zywave aberrometer (Bausch & Lomb Surgical) at a 6.0-mm pupil size. Compared with the ReSTOR IOL, the ReZoom was associated with slightly less total higher-order aberrations (0.75 versus 0.81 μm).

"However, there was a large range in both groups, and the numbers of patients studied are still too small to make any final conclusions," Dr. Knorz said.

Analysis of problems with halos at night in the patients with the ReZoom lens was investigated using Array data for comparison. Among patients with the ReZoom IOL implanted, the majority of patients who complained of halos at night rated them as only mild in severity (84%) while the rest considered them moderate (16%). In contrast, while 41% of patients with the Array IOL implanted considered problems with night halos mild, 41% rated them as moderate, and 10% felt the halos were severe.

"These data indicate the improved optical design of the ReZoom also leads to a clinically significant improvement in performance over the Array IOL," Dr. Knorz said.