[Simulation of night myopia in pseudophakic eyes].
OBJECTIVE
Eyes with an intraocular lens (IOL) implanted that have no accommodative ability are likely to have night myopia caused by Purkinje's shift and chromatic aberration. We evaluated the changes in retinal images caused by night myopia in various IOL-implanted eyes by simulation using model eyes.


METHODS
A polymethylmethacrylate (PMMA) IOL, soft acrylic IOLs, and high-refractive-index silicone IOLs were prepared, and inserted into the model eye. The image plane of the model eye was determined as the line image at which a slit light of 560 nm was best focused, which was regarded as emmetropic condition under photopic vision. A slit light of 505 nm was then directed into the model eye. Its line image on the image plane was blurred, which was regarded as myopic condition under scotopic vision. Under each condition, the modulation transfer functions (MTF) were calculated and the line images were photographed.


RESULTS
The degree of reduction of MTF and blurring of the line image under the night myopic condition was in the order of PMMA < soft acrylic < high refractive index silicone IOL.


CONCLUSIONS
Eyes with a soft acrylic or high-refractive-index silicone IOL may have more intense night myopia caused by chromatic aberration.
Aoshima
S
S
Department of Ophthalmology, Hamamatsu University School of Medicine, Japan.
Nagata
T
T
Watanabe
I
I
D002386:Cataract / Q000503:physiopathology; D006801:Humans; D007910:Lenses, Intraocular; D008954:Models, Biological; D009216:Myopia / Q000209:etiology*; D013995:Time