Background: The implantation of a diffractive multifocal lens (dMIOL) as alternative to a monofocal lens is justified if after surgery there is practically no need to wear glasses.
Patients and methods: 31 patients had an implantation of a total of 35 dMIOLs (3M 815 LE). We evaluated the visual acuity, the refractive data and the patients' attitude to wearing glasses. The average age was 67.0 +/- 11.8 years. Follow up took place after 18.7 +/- 5.4 months.
Results: The mean value of the uncorrected distance acuity was 0.59 +/- 0.17 and the corrected distance acuity 0.96 +/- 0.13. The uncorrected near acuity amounted to Jg 2.40 +/- 0.94, best distance correction was Jg 1.49 +/- 0.55. The patients still accepted an average of 0.68 +/- 0.37 dpt for the best near correction (near vision over the diffractive near focus) and thus achieved Jg 1.46 +/- 0.55. At the best distance correction plus 3.5 dpt, the near visual acuity was improved to 1.03 +/- 0.17. 54.8% of the patients indicated that they did not use glasses at all. 32.3% stated that they only used glasses for reading. 9.7% wore bifocals all the time, and 3.2% always used glasses for the distance.
Conclusions: Regarding distance vision, the dMIOL is equivalent to monofocal lenses. Without any correction the results of the dMIOLs for the near vision are superior to monofocal lenses. Glasses can be dispensed with if the uncorrected visual acuity of the operated eye is at least 0.6 Jg 2-3 after surgery and the other eye too, does not need any correction. In case the postoperative visual acuity is worse, good visual acuity of the other eye may render glasses unnecessary. Part of the patients put up with a correctable loss of visual acuity in order not to become dependent on glasses. The need to wear glasses may be decreased considerably by implanting a dMIOL in both eyes and by avoiding postoperative refraction errors.