Accommodating Lens System with Magnetic Support
Preußner P. R.
Purpose: The approaches known so far to restore accommodation after cataract surgery are limited by postoperative fibrosis and shrinkage of the capsular bag. Any movement stable on a long timescale inside the bag seems to be impossible at current state of the art, including a hinge haptics as well as a moving elastic or viscose fluid.
Method: We propose a movement of the whole capsular bag including IOL on the optical axis instead of a movement inside the bag. Radial zonula movements and forces have to be redirected into axial ones. This redirection can be perfomed passively by a magnetic field. Tiny permanent magnets are implanted into the capsular bag. They are repelled by other permanent magnets fixed at the outer eye. A contraction of the ciliary muscle induces a reversible movement to the forward direction which is only influenced by the neural control circuits of the brain.
Results: Model calculations show that the procedure is relatively insensitive (stable) against all expected parameter variations. Prototypes could be manufactured and implanted into enucleated porcine eyes. As a spin-off product a capsular tension ring which is laser weldable inside the eye has been developped and successfully tested in living rabbit eyes.
Conclusions: The current state of the project is presented.
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