A novel brain mapping technique has provided the first quantitative, dynamic visualization of the spreading wave of cortical atrophy in the brains of living patients with Alzheimer disease (J Neurosci 2003;23:994-1005).
Using this unique mapping method, Australian neuroscientists were able to visualize dynamic patterns of atrophy in 52 high-resolution MRI scans of 12 patients with AD and 14 elderly matched controls. Based on these scans, dramatic time-lapse videos were created, showing sequential loss of gray matter in four dimensions as it spread over time from temporal and limbic cortices into frontal and occipital brain regions, while sparing sensori-motor areas. The visualized patterns of cortical atrophy correlated with the AD patients' progressively declining cognitive ability and mirrored the sequence of neurofibrillary tangle accumulation observed at autopsy. AD patients were found to lose an average of 5.3% grey matter per year compared to a loss of only 0.9% in the healthy volunteers.
In the future, such images may offer researchers a potent tool for assessing the impact of therapies on dementia as well as for evaluating the spread of the disease.
