Implantable lens could warn of Alzheimer's disease
As is the case with so many other things, the sooner that Alzheimer's disease is detected, the more that can be done to slow its progress. An experimental implantable lens could help, by changing in appearance at the early stages of the illness.
Developed by scientists at the Korea Institute of Machinery and Materials (KIMM), the transparent biocompatible polymer lens would be implanted behind the cornea, where it wouldn't interfere with the patient's vision.
The device has a grate-like array of minuscule parallel lines etched directly onto its surface. A layer of transparent hydrogel, lying over top of that grate, likewise has an array of parallel slits running through it. Under normal conditions, the lines and the slits align in such a way that they form a neutral pattern.
However, if even trace amounts of biomarker chemicals associated with Alzheimer's are present in the ocular fluid, they will cause the hydrogel to contact. As it does so, the spacing of its slits will change. As a result, when combined with underlying lines on the lens itself, they will produce what's known as a moiré pattern. This is a sort of strobing pattern, sometimes seen on TV screens when finely striped clothing or other stripy items are being displayed.
Although the lens' moiré pattern wouldn't be visible to the patient, it could be detected by a microscope placed against their eye as part of a regular examination. The technology has already been tested on extracted pig eyes.
A paper on the study, which is being led by KIMM researcher JaeJong Lee, was recently published in the journal Bioactive Materials.