Brain scan detects Alzheimer’s with 98% accuracy

A simple brain scan could diagnose those with early-stage Alzheimer’s at a rate of 98 per cent accuracy, a new study suggests. Researchers from Imperial College London have developed an algorithm to work in conjunction with standard MRI technology to produce speedy results.

Instead of relying on a vast number of memory and cognitive tests, as well as scans, the new technique is straightforward and produces a diagnosis in 12 hours. Cutting down months of waiting means an individual could begin to be treated for Alzheimer’s more quickly.

The algorithm was tested on 400 people, all of whom had 115 regions of their brains analysed for anomalies. These include changes in size, shape and texture, which not only help form a diagnosis, but could also offer clues to the cause of the neurodegenerative condition.

Professor Eric Aboagye, who led the study, said: “Currently no other simple and widely available methods can predict Alzheimer's disease with this level of accuracy, so our research is an important step forward.

“Waiting for a diagnosis can be a horrible experience for patients and their families. If we could cut down the amount of time they have to wait, make diagnosis a simpler process, and reduce some of the uncertainty, that would help a great deal.”

It’s hoped the new diagnostic tool could be rolled out on the NHS in the next two or three years. Alzheimer’s is the most common type of dementia and more than half a million people in the UK are living with the disease. Those affected by it lose brain cells, causing areas of the brain to shrink and memory to be lost.

Often, forgetting recent events or repeating questions can be attributed to the natural ageing process when they’re actually the precursor to Alzheimer’s. To assess how well such small memory issues could be picked up by the MRI and algorithm combination, the scientists included 172 people diagnosed with mild cognitive impairment in the study.

Around three-quarters of these individuals were correctly identified without the use of memory test results. The current methods of diagnosis can see some people with suspected dementia being monitored for months or years before a conclusion is attained.

It can take between two and five years for mild cognitive impairment to develop into full dementia, but as there’s no cure it’s better to be diagnosed early with the hope of slowing the condition’s progress.

The Imperial College scientists found there are early signs of Alzheimer’s in areas of the brain that had not previously been linked to dementia. These include the cerebellum, which is responsible for regulating physical activity, and the ventral diencephalon, which is linked to hearing and sight.

It would make sense for the memory centre of the brain, the hippocampus, to be the most changed. Researchers found only 26 per cent of people with Alzheimer’s were identified by focusing on that area of the organ, however.

Professor Aboagye added: “This could help people avoid weeks to months of anxiety after first going to see their GP as they wait for results from cognitive tests and to get a diagnosis.”