Pictures obtained via tau PET, a new imaging method used to diagnose Alzheimer’s disease, correspond to a higher degree to actual changes in the brain than conventional methods, according to researchers at Lund University, Sweden. This development increases the opportunities to formulate drugs to combat the disease, they suggest.

There are several different methods of producing images showing changes in the brain associated with Alzheimer’s disease. The tau PET method reveals the presence of a protein in the brain, tau, with the help of a gamma camera and a specially selected radioactive molecule (F-AV-1451).

The brain of an Alzheimer’s patient in a tau PET image. Image credit: M. Schöll. Tau has an important function in assisting the transport of various substances within the brain’s nerve cells. People with Alzheimer’s disease have raised levels of tau, leading to accumulation of the protein in the brain cells and gradually to cell death.

A recent study carried out by Lund University and Skåne University Hospital provided researchers the ability to compare tau PET images and brain tissue from the same person for the first time. The brain tissue came from a person who died having recently undergone examination with the new imaging method.

“The person who was examined had a mutation that led to the same type of accumulation of tau in the brain as in Alzheimer’s disease," says Oskar Hansson, professor at Lund University and consultant at Skåne University Hospital. "A single case study might seem insignificant, but since there are areas with a lot of tau stored and others with less tau in the same brain, it is sufficient to examine one person in order to verify whether the imaging method works.”

Interest from the research community in imaging methods focusing on tau is growing. A reliable reproduction of tau protein in the brain is considered a more relevant marker and a better diagnostic tool than competing methods already in use.

The researchers are now focusing on tracking aggregation of tau in the brain over time and connections with diagnostics using spinal fluid samples.