Pharmacokinetic modelling for the simultaneous assessment of perfusion & 18F-flutemetamol uptake in cerebral amyloid angiopathy using a reduced PET-MR acquisition time: Proof of concept Link to paper on NeuroImage. Authors Giorgos Papanastasiou, Mark A. Rodrigues, Chengjia Wang, Kerstin Heurling, Christophe Lucatelli, Rustam Al-Shahi Salman, Joanna M. Wardlaw, Edwin J.R. van Beek, Gerard Thompson Abstract Purpose: Cerebral amyloid angiopathy (CAA) is a cerebral small vessel disease associated with perivascular β-amyloid deposition. CAA is also associated with strokes due to lobar intracerebral haemorrhage (ICH). 18F-flutemetamol amyloid ligand PET may improve the early detection of CAA. We performed pharmacokinetic modelling using both full (0–30, 90–120 min) & reduced (30 min) 18F-flutemetamol PET-MR acquisitions, to investigate regional cerebral perfusion & amyloid deposition in ICH patients. Methods: Dynamic18F-flutemetamol PET-MR was performed in a pilot cohort of sixteen ICH participants; eight lobar ICH cases with probable CAA & eight deep ICH patients. A model-based input function (mIF) method was developed for compartmental modelling. mIF 1-tissue (1-TC) & 2-tissue (2-TC) compartmental modelling, reference tissue models & standardized uptake value ratios were assessed in the setting of probable CAA detection. Results: The mIF 1-TC model detected perfusion deficits & 18F-flutemetamol uptake in cases with probable CAA versus deep ICH patients, in both full & reduced PET acquisition time (all P < 0.05). In the reduced PET acquisition, mIF 1-TC modelling reached the highest sensitivity & specificity in detecting perfusion deficits (0.87, 0.77) & 18F-flutemetamol uptake (0.83, 0.71) in cases with probable CAA. Overall, 52 & 48 out of the 64 brain areas with 18F-flutemetamol-determined amyloid deposition showed reduced perfusion for 1-TC & 2-TC models, respectively. Conclusion: Pharmacokinetic (1-TC) modelling using a 30 min PET-MR time frame detected impaired haemodynamics & increased amyloid load in probable CAA. Perfusion deficits & amyloid burden co-existed within cases with CAA, demonstrating a distinct imaging pattern which may have merit in elucidating the pathophysiological process of CAA. Keywords 18F-flutemetamol uptake Cerebral amyloid angiopathy Magnetic resonance imaging Perfusion Pharmacokinetic modelling Positron emission tomography Related links Link to paper on NeuroImage Professor Joanna Wardlaw Professor Edwin van Beek Professor Rustam Al-Shahi Salman Dr Gerard Thompson Dr Mark Rodrigues Dr Christophe Lucatelli Brain & nervous system Small vessel disease (SVD) Stroke What is a PET scan? What is a PET-MR scan? Social media tags & titles Featured paper: Pharmacokinetic modelling for the simultaneous assessment of perfusion & 18F-flutemetamol uptake in cerebral amyloid angiopathy using a reduced PET-MR acquisition time: Proof of concept @BleedingStroke #MR #PET Publication date 30 Nov, 2020
