Effect of pupil size on visual acuity in a laboratory model of pseudophakic monovision.
OBJECTIVE
To investigate the effect of pupil size on visual acuity in pseudophakic monovision.


METHODS
For the simulation, a modified Liou-Brennan model eye was used. The model eye was designed to include a centered optical system, corneal asphericity, an iris pupil, a Stiles-Crawford effect, an intraocular lens, and chromatic aberration. Calculation of the modulation transfer function (MTF) was performed with ZEMAX software. Visual acuity was estimated from the MTF and the retinal threshold curve. The sizes of the entrance pupil were 2.0, 2.5, 3.0, and 4.0 mm.


RESULTS
Decreasing pupil diameter and increasing myopia progressively improved near visual acuity. For an entrance pupil size of 2.5 mm and a refractive error of -1.50 diopters, the logMAR value (Snellen; metric) in the non-dominant eye at 40 cm was 0.06 (20/23; 6/6.9).


CONCLUSIONS
Knowledge of the patient's pupil diameter at near fixation can assist surgeons in determining the optimum degree of myopia for successful monovision.
Kawamorita
Takushi
T
Department of Orthoptics and Visual Science, Kitasato University School of Allied Health Sciences, 1-15-1 Kitasato, Sagamihara, Japan. kawa2008@kitasato-u.ac.jp
Uozato
Hiroshi
H
Handa
Tomoya
T
Ito
Misae
M
Shimizu
Kimiya
K
D006801:Humans; D008954:Models, Biological; D009216:Myopia / Q000503:physiopathology; D019591:Pseudophakia / Q000503:physiopathology*; D011680:Pupil / Q000502:physiology*; D015349:Vision, Monocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology*