New Brain Scan Tests for Alzheimer's Chemical marks amyloid proteins that show up in scan By Mark Russell, Newser Staff Posted Apr 9, 2012 3:56 AM CDT 5 comments Comments A new test for amyloid proteins in the brain promises to improve the diagnosis of Alzheimer's disease. (Shutterstock) (Newser) – A new test to help detect Alzheimer's disease has been approved by the FDA, raising hopes of improving early detection of the degenerative brain disorder, reports the Wall Street Journal. The test uses a radioactive agent that tags a protein called amyloid, which, when present in the brain, is a major sign of Alzheimer's. After an individual takes the agent—florbetapir—the brain can be scanned for clumps of amyloids. The chemical doesn't come cheap, though—Eli Lilly is charging $1,600 per dose. But it is a big step forward. Until now, the presence of amyloid plaques could only be checked by an autopsy. The chemical isn't a complete answer, either, as amyloids can be found in healthy people, too. "It is likely to play an important role in learning both how to diagnose and treat the disease, but it's still an open question at this point for asymptomatic people," said one doctor.