Single brain scan helps diagnose Alzheimer's disease

A recent research has used machine learning technology to look at structural features within the brain, including in regions not previously associated with Alzheimer's. The advantage of the technique is its simplicity and the fact that it can identify the disease at an early stage when it can be very difficult to diagnose. The research is published in the Nature Portfolio Journal, Communications Medicine.

Doctors currently use a raft of tests to diagnose Alzheimer's disease, including memory and cognitive tests and brain scans. The scans are used to check for protein deposits in the brain and shrinkage of the hippocampus, the area of the brain linked to memory. All of these tests can take several weeks, both to arrange and to process.

The new approach requires just one of these-a magnetic resonance imaging (MRI) brain scan taken on a standard 1.5 Tesla machine, which is commonly found in most hospitals.

The researchers adapted an algorithm developed for use in classifying cancer tumours, and applied it to the brain. They divided the brain into 115 regions and allocated 660 different features, such as size, shape and texture, to assess each region. They then trained the algorithm to identify where changes to these features could accurately predict the existence of Alzheimer's disease.

Using data from the Alzheimer's Disease Neuroimaging Initiative, the team tested their approach on brain scans from over 400 patients with early and later stage Alzheimer's, healthy controls and patients with other neurological conditions, including frontotemporal dementia and Parkinson's disease. They also tested it with data from over 80 patients undergoing diagnostic tests for Alzheimer's.

They found that in 98 per cent of cases, the MRI-based machine learning system alone could accurately predict whether the patient had Alzheimer's disease or not. It was also able to distinguish between early and late-stage Alzheimer's with fairly high accuracy, in 79 per cent of patients.

Reference: Single brain scan can diagnose Alzheimer's disease, IMPERIAL COLLEGE LONDON; Communications Medicine