THE EYE AS A TOOL FOR DETECTING BRAIN DISEASE

Edited by, SNEHA MAVIS

The human eye and brain share significant vascular and neurological similarities therefore our eyes have been found to provide a direct window into brain pathology. The distinctive characteristics of the human eye allow them to be used as relatively affordable biomarkers for Alzheimer's disease (AD) and other mental disorders.

According to research, certain visual symptoms have been linked to the onset of dementia and the formation of senile plaques in the brain's visual regions. Direct visualisation of the hallmarks of AD in the retina  may be the most promising AD biomarker because of its specificity for AD. However, more research is needed to confirm that Aβ plaques are present in retinal tissues and that these retinal deposits are predictive of cerebral deposits.

Non-retinal biomarkers for AD include pupillary reactions such as pupil size and pupillary sensitivity to light. Eye movements are crucial because AD patients have difficulty reading due to suboptimal eye motions that are considered to be linked to memory.

The study examined the retinas of almost 200 persons to see if thee were any differences between those with and without AD. According to the results, people with a healthy brain have a rich network of blood veins in their retina, which can be seen during an eye exam. This small web of blood arteries was far less visible in people who had an unhealthy brain or Alzheimer's disease. The researchers took high-resolution images of the tiny blood vessels in the retina using a non-invasive technology called optical coherence tomography angiography (OCTA).