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Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
Gravitational pseudoaccommodation in patients with aphakic iris-claw intraocular lenses
Joel-Benjamin Lincke1, Mathias Miller1, Andreas Ebneter1
1From the Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Switzerland.
Purpose:
To assess whether iris-claw intraocular lenses (IOLs) undergo gravitation-dependent changes in position and refraction.
Setting:
Tertiary referral center, Bern, Switzerland.
Design:
Observational case study.
Methods:
Patients with a history of pars plana vitrectomy and IOL exchange with implantation of an aphakic iris-claw IOL (Artisan) were included in this study. Objective refraction was obtained with a handheld autorefractometer, and the IOL position was measured by ultrasound biomicroscopy with the patient prone, sitting, and supine.
Results:
Twenty-one eyes of 19 patients with retropupilary IOLs (13) or prepupillary IOLs (8) were included. The mean spherical equivalent (SE) in the sitting position was -0.81 diopter (D) ± 0.95 (SD), and the mean distance from the endothelium to the anterior edge of the IOL was 3.35 ± 0.72 mm. The mean SE in the supine position was -0.61 ± 1.28 D, whereas the mean SE in the prone position was -1.34 ± 1.17 D (P = .0030). The IOL position changed from 3.50 mm in the supine position to 3.06 mm in the prone position (P < .0001).
Conclusions:
The aphakic iris-claw IOL was subject to significant movement related to gravity. The change in the refractive effect suggests that there is a degree of pseudoaccommodation caused by the forward shift of the aphakic IOL in the face-down position.
Financial Disclosure:
None of the authors has a financial or proprietary interest in any material or method mentioned.
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