[Objective evaluation of apparent accommodation of pseudophakic eyes]

In 23 (9 males and 14 females) pseudophakic eyes which had a biconvex type intraocular lens (IOL) implanted after cataract extraction, we objectively measured changes in the anterior chamber (AC) depth caused by axial movement of the IOL accompanying accommodation of the contralateral phakic fellow eye, using a Schimpflug slit image with an anterior eye segment image analysis system (Nidek, EAS-1000, Japan). In 114 phakic eyes of 57 persons as controls, AC depths accompanying accommodation from distances of 5 m to 30 cm and 10 cm decreased with increasing age. The decreased mean value of AC depth with accommodation from distances of 5 m to 30 cm was 0.17 mm in patients in their teens, 0.15 mm in patients in their 20 s, 0.10 mm in the 30 s, 0.06 mm in the 40 s, 0.05 mm in the 50 s, and 0.03 mm in the 60 s. The decrease of AC depth with accommodation at a distance of 10 cm was 0 in patients in their 60 s. In the pseudophakic eye changes in anterior chamber depth caused by focusing at short distances were less than 0.04 mm, and decreasing rate of anterior chamber depth (DRAC) was less than 1% in all the pseudophakic eyes. Movement of IOL on the optical axis was too subtle to account for apparent accommodation of the pseudophakic eye.