Quality of image of grating target placed in model of human eye with corneal aberrations as observed through multifocal intraocular lenses.
OBJECTIVE
To evaluate the quality of the image of a grating target placed in a model eye viewed through multifocal intraocular lenses (IOLs).


METHODS
Laboratory investigation.


METHODS
Refractive (NXG1 or PY60MV) or diffractive (ZM900 or SA60D3) multifocal IOLs were placed in a fluid-filled model eye with human corneal aberrations. A United States Air Force resolution target was placed on the posterior surface of the model eye. A flat contact lens or a wide-field contact lens was placed on the cornea. The contrasts of the gratings were evaluated under endoillumination and compared to those obtained through a monofocal IOL.


RESULTS
The grating images were clear when viewed through the flat contact lens and through the central far-vision zone of the NXG1 and PY60MV, although those through the near-vision zone were blurred and doubled. The images observed through the central area of the ZM900 with flat contact lens were slightly defocused but the images in the periphery were very blurred. The contrast decreased significantly in low frequencies (P<.001). The images observed through the central diffractive zone of the SA60D3 were slightly blurred, although the images in the periphery were clearer than that of the ZM900. The images were less blurred in all of the refractive and diffractive IOLs with the wide-field contact lens.


CONCLUSIONS
Refractive and diffractive multifocal IOLs blur the grating target but less with the wide-angle viewing system. The peripheral multifocal optical zone may be more influential on the quality of the images with contact lens system.
Kyorin Eye Center, Kyorin University School of Medicine, Mitaka, Tokyo, Japan. inoue@eye-center.org
Makoto
M
Inoue
Toru
T
Noda
Toshifumi
T
Mihashi
Kazuhiko
K
Ohnuma
Hiroko
H
Bissen-Miyajima
Akito
A
Hirakata
D003261:Contact Lenses; D015350:Contrast Sensitivity / Q000502:physiology*; D057108:Corneal Wavefront Aberration / Q000503:physiopathology*; D006801:Humans; D007910:Lenses, Intraocular; D008954:Models, Biological; D012029:Refraction, Ocular / Q000502:physiology