[Clinical results of aphakia correction with bifocal intraocular lenses].

Aim: To evaluate the effect of symmetrical vs. asymmetrical and bilateral vs. unilateral implantation of M LENTIS LS-312 MF 30 multifocal intraocular lenses (IOLs) on visual functions and ergonomic parameters.

Material And Methods: A total of 44 patients (68 eyes) with lens opacities of different intensity were enrolled. Group 1 included 24 patients who underwent symmetrical bilateral multifocal IOLs implantation, group 2--20 patients who received unilateral procedure. Binocular uncorrected near and intermediate visual acuity (VA) under photopic and mesopic conditions, amplitude of pseudoaccomodation, and spatial contrast sensitivity to achromatic sinusoidal gratings were evaluated. Patient's satisfaction with visual results was also analyzed. Taking into account the peculiar design of multifocal IOLs optics, lens rotational stability in the postoperative period was also assessed.

Results: Regardless of lighting conditions binocular distance VA was similarly high in both groups, while binocular near and intermediate VA was higher in group 1 as compared with group 2. The amplitude of pseudoaccomodation in groups 1 and 2 was 3.75 and 3.5 diopters correspondingly. Contrast sensitivity function was of typical shape peaking at intermediate frequencies and gradually decreasing toward higher frequencies. None of the patients from either group required optical correction for distance vision. Two patients from group 2 (and none from group 1) at times were in need of reading vision correction. Another patient from group 2 used spectacles for intermediate work. To evaluate lens rotational stability in the postoperative period, the alignment of axis marks on the IOL with the horizontal meridian of the eye was checked under maximum mydriasis. At the 1-month follow-up, rotation of 10-15 degrees was found in 31 eye, however, none of the patients presented complaints characteristic of IOL decentration.

Conclusion: Symmetrical bilateral implantation of M LENTIS LS-312 MF 30 multifocal IOLs provides advantages over unilateral procedure because not only does it allow to retain high distance VA, but also ensures larger amplitude of pseudoaccomodation at near and intermediate distances.