3M diffractive multifocal intraocular lens: eight year follow-up

To study the long-term results of implantation of the 3M diffractive multifocal intraocular lens (IOL).

Eye Department, ASA, Arendal, Norway.

The study comprised 97 eyes in 72 patients. Follow-up was 8 years. Distance and near visual acuities, refractive results, contrast sensitivity, IOL centration, and neodymium:YAG (Nd:YAG) capsulotomies to treat posterior capsule opacification were evaluated.

All patients without ocular pathology achieved a best corrected visual acuity (BCVA) of 0.5 or better (i.e., 98.7% had a BCVA of 1.0 or better). Without correction, 73.8% of eyes had a Jaeger acuity of J3 or better and with distance correction, 92.1%. Emmetropia or within +/-0.25 diopter (D) of it was achieved in 58.8% of eyes. An astigmatic shift of 0.827 D cylinder correction was induced. This shift was mainly against the rule (0.717 D). Contrast sensitivity was reduced with spatial frequencies of 6 to 18 cycles per degree. No need for spectacles was reported by 54.2% of patients and by 68.0% of those with bilateral implantation. For near tasks, 63.9% of patients never used spectacles. The IOLs were well centered or minimally decentered in 99.0% of eyes. Posterior capsule opacification was treated by Nd:YAG laser capsulotomy in 55.7% of eyes, with a mean time between surgery and treatment of 34.0 months +/- 23.2 (SD).

This long-term study proved the 3M diffractive IOL to be safe and effective despite some reduction in contrast sensitivity at higher spatial frequencies. More than half the patients never wore spectacles; 2 of 3 patients with IOLs in both eyes never wore spectacles. Proper patient selection is crucial.