[Comparative study of 2 types of bifocal implants by measurement of visual acuity and contrast sensitivity]

Evaluation of multifocal IOLs suggests the possibility of two retinal images, one for near and one for distant vision. But the optic principles of multifocal IOLs created overlying images and incident light division. We performed this study to evaluate visual acuity and contrast sensitivity for two types of bifocal IOLs (3M bifocal and IOLAB bifocal IOL) and for a control group of monofocal IOL testing in different levels of luminance simulating the normal environmental conditions of the patient's experience. The results showed a visual functional loss especially at the low luminance level for the 3M bifocal group and at bright luminance for the IOLAB bifocal group, which was previously unknown with and consequences for the indications and exclusions of this kind of IOL.