Contrast sensitivity in patients with a new type of multifocal intraocular lens.

Contrast sensitivity was measured in 13 pseudophakic eyes of ten patients who had a new type of diffractive multifocal intraocular lens (IOL) and compared with an age-matched control group with a conventional monofocal IOL. All selected cases had a postoperative follow-up of four to six months and a corrected visual acuity of 20/20 or better. For distance vision, no significant difference in contrast sensitivity could be found between the two groups, indicating an uncompromised distance focus of the multifocal IOL. For near vision, an overall decrease in the contrast sensitivity of 0.19 log units (mean value across the tested frequency from 1.5 to 18 cycles/deg) was found in the multifocal group when these patients were tested without near addition and compared with the controls with near addition (P less than .05). This indicated the near focus of the multifocal IOL to be somewhat less efficient than the far focus. We find these results promising for the new diffractive multifocal IOL.