Visualizing Progress: Hyperspectral Retinal Imaging for Alzheimer’s Detection.

Visualizing Progress: Hyperspectral Retinal Imaging for Alzheimer’s Detection.

by | Apr 4, 2024 | Alzheimer | 0 comments

Alzheimer’s is a progressive neurodegenerative disease prevalent in the elderly population above 65 years of age. It is the most common form of dementia that gradually impairs thinking, memory and behaviour. It causes a steep decline in cognitive function in patients. The effects are severe enough to interfere with routine day-to-day tasks, ultimately resulting in death in three to eleven years post-diagnosis.

Being progressive in nature, AD develops from a mild to moderate to severe disease presenting a spectrum of symptoms ranging from cognitive difficulties to delusions and paranoia. It affects the parts of the brain responsible for memory, language, and thoughts. At the cellular level, AD is characterized by the formation of abnormal proteinaceous depositions (amyloid plaques) and tangled fibrous bundles called tau or neurofibrillary tangles. These deposits are linked to neuronal death starting from the hippocampus and entorhinal cortex regions. Over time this results in shrinking of brain tissue and loss of neural connections. Patients with severe Alzheimer’s lose all ability to communicate leading to highly impaired quality of life and rely entirely on others increasing the stress on families and the healthcare systems.

The causes of AD are not fully characterised, however, aging alongside environmental, genetic and lifestyle factors have been correlated with the disease. While there are no available cures for Alzheimer’s disease, cholinesterase inhibitors, such as, donepezil, galantamine, and rivastigmine can target disease symptoms in patients with mild to moderate AD. Aducanumab (Aduhelm®), a monoclonal antibody, is the first approved drug that can successfully target beta-amyloid (peptide that forms amyloid plagues). Although this reduces clinical decline in patients, it cannot completely reverse the brain damage. Hence, early detection is the key to successfully manage the disease progression and reduce the overall burden on patients, families, and the healthcare systems.

Presently, AD detection relies on invasive methods, such as, positron emission tomography (PET) scanning or cerebrospinal fluid (CSF) analysis. These approaches are costly and less accessible. Furthermore, due to factors like, access to healthcare and difficulty in symptom recognition, combined with complexity and cost of diagnostic processes, the diagnostic time from first symptom to disease recognition can often span from a few months to more than 5 years.

Hyperspectral retinal imaging is a promising alternative for early detection of AD. Our hyperspectral cameras can efficiently capture the unique spectral profile of Amyloid Beta deposition in the retina of patients. This is a key characteristic of AD. This non-invasive method offers a convenient and cost-effective way for AD detection and assessment of disease progression. It poses the possibility of a scalable population wide screening of individuals at risk of AD.

We have recently finished a trial at the memory clinic of Karlskrona (Sweden). Patients with suspicion of cognitive decline went through a battery of tests (CSF, cognitive test, etc) and were scanned by Mantis camera. We are now working building an algorithm to diagnose Alzheimer using this data.

With increasing aging population worldwide, early detection of AD is crucial for timely and successful disease management. This enables patients and their family to access appropriate treatments to slow down disease progression and improve quality of life. Hyperspectral imaging is a valuable tool for AD detection and offers scalability and accessibility at a low-cost. Hyperspectral retinal imaging holds the key to advancing early detection and broadening our understanding of Alzheimer’s.