"Our brains are connected to both eyes through optic nerve cells, so damage of the brain can lead to damage of the optic tract and retina," says Helen Danesh-Meyer, eye surgeon and 'neuro-ophthalmologist' of the University of Auckland Medical School in New Zealand.
Facial loss is often one of the first symptoms of people with a nerve condition. Proof of the connection between degeneration of the optical tracts and diseases like Alzheimer have been known since the eighties, but now there are also instruments that can measure it through the iris. An example is the laser-camera technique retina tomography (HRT), and a laser technique (GDx) which are both used to measure the form and thickness of the nerves behind the eye.
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Future Vision by Erwin Van Lun on this article
It’s said iridology has been known for the ancient Greeks, the Egyptians and the Chinese. It still exists, but because it’s scientifically very little explained, there’s still a lot of scepticism (Dutch). Now that we’re slowly measuring on very detailed levels, we can also show things we couldn’t before and thus put aside as ‘scientifically unproven’. Now we can measure, better and better, we can get new insights, develop diagnoses to eventually let humans on earth live longer.