Diagnosing Alzheimer’s disease with Brain Imaging

Diagnosing Alzheimer’s disease has been difficult because the only really accurate diagnosis is an autopsy performed after the person afflicted with the disease has died. Doctors can administer a variety of tests and screenings, however, and usually predict with an 80-90 percent accuracy if a person truly has Alzheimer’s disease.

Diagnosing Alzheimer’s disease usually means visiting the doctor’s office for a complete physical exam, going over a person’s complete medical history, ordering lab work, and administering several cognitive and memory screens. All these tests are undertaken to rule out the possibility of other causes. In other words, diagnosing Alzheimer’s disease is no simple procedure.

Brain Imaging and Diagnosing Alzheimer’s Disease

Researchers who study the diagnosing Alzheimer’s disease have recently developed a PET imaging method that shows levels of beta-amyloid in those who do have Alzheimer’s. The researchers came from both the United States and Sweden to team up to develop this advance in imaging. Their research was funded by the Alzheimer’s Association, the National Institute on Aging, and two Swedish organizations.

Beta-amyloid is a protein fragment, very small and very sticky, that tends to accumulate in clumps within the brain. Many scientists believe that at some point, this accumulation could be a key factor in what damages the brain cells of those with Alzheimer’s disease.

The scientists used an imaging strategy that sent Pittsburgh Compound B (or PIB) traveling through the bloodstream where it could enter a person’s brain and attach itself to any of the beta-amyloid clumps. An imaging procedure then captured these areas.

The scientists are hopeful that this new technique will lead to doctors diagnosing Alzheimer’s disease quite a bit earlier, and it is thought that it may be able to identify Alzheimer’s in those who aren’t yet showing any symptoms. This research has already led to a much better understanding of the disease.

SPECT is a scanning procedure that is quite similar to PET. It also can be used to differentiate different diseases that cause dementia, and is increasingly thought to be very useful for diagnosing Alzheimer’s.

Another means of diagnosing Alzheimer’s disease is an MRI, which can detect brain abnormalities in those with the disease. It is being studied now to determine if MRIs can also detect changes in the brains of people who are suffering from cognitive deficiencies.

Neuroimaging is used in diagnosing Alzheimer’s disease by either directly or indirectly taking images of the brain’s structure. There are two broad categories here: structural imaging and functional imaging. Functional imaging is more accurate in diagnosing Alzheimer’s disease.

As scientists continue to develop and refine new methods for diagnosing Alzheimer’s disease, there is at least some hope that as symptoms are detected earlier and earlier, more effective treatments will also be developed, eventually leading to a cure.