A NEW MRI RATIO METHOD FOR IN-VIVO ESTIMATION OF SIGNAL HYPOINTENSITYIN AGING AND ALZHEIMERS-DISEASE

1. Alzheimer's Disease (AD) is accompanied by a disruption in iron met abolism. There is no universally accepted method for detecting brain i ron. 2. The authors have developed a novel ''ratio'' method which uses the red nucleus as an internal reference. We postulated that this met hod would improve our sensitivity in detecting differences in MRI sign al intensities and that it would allow us to measure brain iron deposi tion. 3. The ratio method reasonably reproduced previous reports of th e normal deposition of iron in brain that occurs with aging. It failed to distinguish any differences in three brain areas: putamen, left fr ontal lobe and whole slice in AD patients versus age and sex matched c ontrols. 4. It also failed to detect differences with AD progression o r severity. 5. The ratio method itself warrants further investigation.