Tracy Robert Melzer1,2, Richard Watts1,3, Michael R. MacAskill1,2, Ross J. Keenan4, Ajit Shankaranarayanan5, David C. Alsop6, Leslie Livingston1,2, John C. Dalrymple-Alford1,7, Tim J. Anderson1,2
1Van der Veer Institute for Parkinson's & Brain Research, Christchurch, New Zealand; 2Medicine, University of Otago, Christchurch, New Zealand; 3Physics & Astronomy, University of Canterbury, Christchurch, New Zealand; 4Christchurch Radiology Group, Christchurch, New Zealand; 5GE Healthcare, Menlo Park, CA, United States; 6Beth Israel Deaconess Medical Center, Boston, MA, United States; 7Psychology, University of Canterbury, Christchurch, New Zealand
We used structural MRI and pseudo-continuous ASL to characterize brain changes associated with cognitive status in Parkinsons disease (PD). PD patients were classified as cognitively normal (PD-N), with mild cognitive impairment (PD-MCI), or with dementia (PD-D). PD-MCI and PD-D showed decreased cortical perfusion relative to controls and PD-N. Only PD-D exhibited widespread grey matter atrophy. The structure-function dissociation in PD-MCI suggests that functional blood flow changes occurred before detectable structural changes in cognitive decline associated with PD. This dissociation provides a promising biomarker sensitive to cognitive status in PD.