Researchers found a marker used to detect plaque in the brain, which may help doctors make more precise diagnoses between two common types of dementia – Alzheimer’s and frontotemporal lobar degeneration (FTLD).

FTLD develops when the frontal lobes of the brain begin to atrophy or shrink.

Dr. Ronan Factora, a geriatrician at the Cleveland Clinic, did not take part in the study, but said the study was helpful because FTLD can often present like Alzheimer’s, and it’s useful to know how to separate the two conditions.

Researchers at the University of California in San Francisco looked at 107 people who had early-onset Alzheimer’s or FTLD.

The patients underwent a brain PET scan using a PIB marker, which detects plaque in the brain that is related to Alzheimer’s, but not associated with FTLD.

The patients then underwent another PET scan, this time using a FDG marker, which finds changes in the brain’s metabolism. The researchers compared the two scans, and results show the PIB marker performed at least as well as the FDG marker in differentiating between the two conditions, but had higher sensitivity and more accuracy.

When the PIB PET scan becomes more available, it could increase the accuracy of diagnosing both conditions.

“We’re getting a lot better technology in trying to identify these dementias early on,” Factora said. “Particularly for these two – Alzheimer’s and frontotemporal lobar degeneration – early diagnosis is important for planning purposes. We still don’t have any treatment that is going to help stop the disease process overall, but it’s important for the families to know what it is you are confronting.”

The study is published in the journal Neurology.