MRI of Alzheimer's Disease Imaging Amyloid Plaques in Persons With and Without Memory Problems

The study will investigate the possibility of detecting early signs of Alzheimer's disease using magnetic resonance imaging (MRI). If plaques, types of damage, can be imaged by MRI, the procedure could be used in clinical trials and may also help in the clinical diagnosis of patients. Alzheimer's disease, a progressive disease, is a major cause of functional disability and institutionalization, affecting 4.5 million people in the United States, a number that will more than triple by 2030 as the population ages.

Patients ages 55 to 90 who have mild symptoms of Alzheimer's disease and who are in good health may be eligible for this study. Twenty patients will be recruited from Johns Hopkins' Alzheimer's Disease Research Center. There will also be a control group of 20 people without the disease.

Healthy patients and volunteers will have a clinical MRI brain scan and a neurological examination at Johns Hopkins Hospital before the 7T MRI scan. Also, patients will have a Mini-Mental State Examination, a standardized test to evaluate memory, done at Johns Hopkins within 4 weeks of the 7T MRI. This study uses a device situated at the NIH Bethesda campus that operates at a high magnetic field strength of 7 Tesla, that is, the unit used to measure the strength of a strong magnet. The Food and Drug Administration has categorized MRI up to 8 Tesla as not a significant health risk. MRI scanning is routinely done at magnetic field strengths up to 4T. MRI images are created through the use of a large magnet and radio waves. During the procedure, patients lie on a table moved into a strong magnetic field. They are asked to lie still but can easily hear and speak to research staff. A respiratory belt is placed around the chest, and a finger probe is placed on the finger, to monitor breathing and heart rate. For obtaining a better picture, a special lightweight coil may be placed on or around the patient's head. The scan takes from 20 minutes to 2 hours, with most scans at 45 to 90 minutes. Due to limited experience with the use of 7T MRI and its investigational nature, patients will be asked to complete a questionnaire immediately after the study. They will be asked about their comfort level and if they experienced unusual sensations. Answers will be reviewed with patients by an experienced MRI investigator to get details of any unusual sensations reported. If patients experience unusual sensations, they are followed up by phone within 24 hours.

This study wi...