Peter Bohn, Abstract Co-Author: Nothing to Disclose

Isabelle Riederer, Abstract Co-Author: Nothing to Disclose

Christine Preibisch, Abstract Co-Author: Nothing to Disclose

Panos Alexopoulos, Abstract Co-Author: Nothing to Disclose

Markus Schwaiger MD, Abstract Co-Author: Research Grant, Siemens AG

Stefan Forster MD, Presenter: Research Consultant, Bayer AG Speakers Bureau, General Electric Company Research Consultant, Merck KGaA Research Consultant, Piramal Enterprises Limited

Previous studies showed specific abnormality patterns as well as high pattern accordance between cortical PET hypometabolism-, ASL MRI hypoperfusion- and T1w MRI atrophy in Alzheimer´s disease (AD) and mild cognitive impairment (MCI). Whereas former studies were conducted on separate scanners at different time points we aimed to compare these three methods directly utilizing simultaneous PET/MRI in patients with MCI, patients with AD and healthy control subjects.

19 AD- and 14 MCI patients and 11 matched healthy elderly controls (HC) were included in this prospective study. Patients and subjects were examined on a Siemens mMR Biograph integrated PET/MRI scanner, using a simultaneous acquisition protocol (pulsed arterial spin labeling (PASL) MRI, T1w MPRAGE MRI and 18F-FDG-PET). Matlab, SPM8/VBM8 based preprocessing was executed and voxelwise statistical comparisons between AD, MCI and HC were carried out (t-tests; p>0.001; kE=20).

Relative to HC distinct hypometabolism and hypoperfusion occurred in bilateral posterior cingulate- and bilateral superior parietal cortex for AD and left superior parietal cortex for MCI, while mild atrophy in the latter regions occurred only for AD. In MCI and AD most distinct atrophy without co-localization of hypometabolism and hypoperfusion occurred in bilateral medial- and inferior temporal cortical regions.

Applying simultaneous PET/MRI in MCI and AD, patterns of cortical hypoperfusion and hypometabolism showed high correspondence and did mainly not result from effects of regional cortical atrophy, which occurred most distinctively in medial- and inferior temporal regions. We suggest that in a group-based evaluation PASL MRI delivers comparable results to 18F-FDG-PET in the diagnosis of neurodegenerative MCI/AD, having the advantages of non-invasiveness and non-radiation exposure. PASL MRI might be a future alternative to 18F-FDG-PET in the PET/MRI diagnostic work-up of patients with neurodegenerative dementia, i.e. in combination with amyloid-PET. However, PASL MRI needs further evaluation on a patient basis and regarding its quantitative features.

Our abstract has high clinical relevance, as non-invasive and radiation exposure free neuroimaging methods such as arterial spin labeling MRI have high potential to be translated in the diagnostic work-up of patients with neurodegenerative dementia and other diseases.

Bohn, P, Riederer, I, Preibisch, C, Alexopoulos, P, Schwaiger, M, Forster, S, 18F-FDG-PET, Pulsed Arterial Spin Labeling MRI and Structural MRI in Mild Cognitive Impairment and Alzheimer’s Disease: A Simultaneous PET/MRI Study.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14001921.html