[Theoretical and clinical image properties of refractive 3-zone multifocal lenses with different distribution of far and near focus].
BACKGROUND
The optic of common multifocal IOLs (MIOLs) is effecting an even light distribution to far and near focus. New MIOL designs were developed by Jacobi to improve distance or near contrast, by favouring the far or near focus with 60-70% of the light energy. For binocular implantation, an "asymmetrical" MIOL-combination is possible with accentuation of distance focus in one eye and near focus in the other eye.


METHODS
By means of an optical system described by Jacobi and Reiner "artificial eyes" with the new MIOLs were implanted in 7 young healthy subjects and contrast sensitivity was measured for distance and near. Clinical implantation was performed in 46 patients and visual acuity, contrast sensitivity, depth of focus and binocular functions were determined after 6 months.


RESULTS
MIOL designs with accentuation of distance vision did not show a significant reduction of distance contrast compared with a monofocal IOL. Asymmetrical binocular implantation of the new lenses resulted in a better distance and near contrast sensitivity than implantation of MIOLs with an even light distribution. Binocular functions were not impaired.


CONCLUSIONS
Asymmetrical implantation of the new MIOLs with uneven light distribution to far and near focus enables distance vision comparable to monofocal IOLs, but with the advantage of an increased depth of focus.
Eisenmann
D
D
Universitäts-Augenklinik Giessen.
Jacobi
K W
KW
Krzizok
T
T
Reiner
J
J
D000328:Adult; D000368:Aged; D015350:Contrast Sensitivity; D003867:Depth Perception; D005260:Female; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D055095:Optics and Photonics; D011446:Prospective Studies; D011474:Prosthesis Design; D012029:Refraction, Ocular; D015348:Vision, Binocular; D014792:Visual Acuity
Theoretische und klinische Abbildungseigenschaften refraktiver 3-Zonen-Multifokallinsen mit unterschiedlicher Gewichtung von Fern- und Nahfokus.