Recent studies show that a reduction in size of the hippocampus (which can be detected by using MRI) and a reduction in temporal and parietal lobe blood flow (SPECT) and glucose metabolism (PET) are often early diagnostic features of Alzheimer’s disease. However, using MRI to assess the hippocampus requires sophisticated, labor-intensive research techniques (visual inspection isn’t good enough). Also, these abnormalities detected by MRI and SPECT/PET can occur as part of normal aging and in other neurologic disorders. Although none of these techniques are diagnostic by themselves, they can help when the clinical picture is unclear.
Functional MRI is a new technique that involves looking at changes in hemoglobin oxygen saturation (indicates brain tissue oxygen use), usually while the subject is performing a test of attention or memory. Functional MRI is in its infancy but may well become the wave of the future. A major problem is that its results are worthless if people cannot keep their heads completely still while they lie in the scanner.
The decision about which brain imaging technique to use remains in the hands of your physician. Nonetheless, if you have memory loss, knowing the basics outlined here will make you a more informed consumer about the role of these brain imaging procedures in diagnosing the cause of your memory loss.
Taken From: The Memory Program How to Prevent Memory Loss
and Enhance Memory Power
