Diagnostic performance of regional cerebral blood flow images derived from dynamic PIB scans in Alzheimer’s disease

Abstract

Background In clinical practice, visual assessment of glucose metabolism images is often used for the diagnosis of Alzheimer’s disease (AD) through 2-[ 18 F]-fluoro-2-deoxy- d -glucose (FDG) positron emission tomography (PET) scans. However, visual assessment of the characteristic AD hypometabolic pattern relies on the expertise of the reader. Therefore, user-independent pipelines are preferred to evaluate the images and to classify the subjects. Moreover, glucose consumption is highly correlated with cerebral perfusion. Regional cerebral blood flow (rCBF) images can be derived from dynamic 11 C-labelled Pittsburgh Compound B PET scans, which are also used for the assessment of the deposition of amyloid-β plaques on the brain, a fundamental characteristic of AD. The aim of this study was to explore whether these rCBF PIB images could be used for diagnostic purposes through the PMOD Alzheimer’s Discrimination Tool. Results Both tracer relative cerebral flow ( R 1 ) and early PIB (ePIB) (20–130 s) uptake presented a good correlation when compared to FDG standardized uptake value ratio (SUVR), while ePIB (1–8 min) showed a worse correlation. All receiver operating characteristic curves exhibited a similar shape, with high area under the curve values, and no statistically significant differences were found between curves. However, R 1 and ePIB (1–8 min) had the highest sensitivity, while FDG SUVR had the highest specificity. Conclusion rCBF images were suggested to be a good surrogate for FDG scans for diagnostic purposes considering an adjusted threshold value. Electronic supplementary material The online version of this article (10.1186/s13550-019-0528-3) contains supplementary material, which is available to authorized users.

Feasibility of pharmacokinetic parametric PET images in scaled subprofile modelling using principal component analysis

“…PET was acquired using either a Siemens Biograph 40mCT or 64mCT scanner (Siemens Medical Solution, USA) that were harmonized regarding their performance and reconstructions. There were no statistically significant differences between data acquired from different scanners ( Peretti et al, 2019c , Peretti et al, 2019b ). Radiotracers were synthesized at the department of Nuclear Medicine and Molecular Imaging of the UMCG, according to Good Manufacturing Practice, and were administered via a venous cannula.…”

“…Furthermore, it might be interesting to use a longitudinal dataset to evaluate its ability to measure disease progression and to predict conversion to AD for patients at high risk (MCI+). Additional research is needed to evaluate the use of R 1 parametric images as these might not be sensitive enough to detect small changes during a follow-up of a patient ( Peretti et al, 2019b , Peretti et al, 2019c ). Moreover, all images were only tested against an AD DP.…”

“…The quantification of these Aβ deposits can be obtained by means of pharmacokinetic modelling of the tracer using the simplified reference tissue model 2 (SRTM2) ( Peretti et al, 2019a , Yaqub et al, 2008 ), which provides a measure of Aβ load through binding potential ( BP ND ), as well as information on regional cerebral blood flow (rCBF) through the relative tracer flow parameter ( R 1 ) ( Chen et al, 2015 , Meyer et al, 2011 , Peretti et al, 2019c , Peretti et al, 2019b ). Previous studies have shown that rCBF is closely related to glucose metabolism measured with [ 18 F]-2-fluoro-2-deoxy- d -glucose (FDG) PET ( Jueptner and Weiller, 1995 ), another PET radiotracer used routinely for the classification of AD patients and, therefore, has been suggested as an alternative to performing two scans ( Meyer et al, 2011 , Peretti et al, 2019c , Peretti et al, 2019b ). This approach is of great interest since it might reduce patient discomfort, exposure to radiation, and study costs.…”

Effect of Shortening the Scan Duration on Quantitative Accuracy of [18F]Flortaucipir Studies

“…For the analysis of [ 18 F]flortaucipir scans, most studies prefer semiquantitative measures due to their practical applicability and computational simplicity [7][8][9]. However, studies involving dynamic imaging provided more accurate and precise pharmacokinetic parameters and provide estimates for relative tracer delivery (R 1 ) or relative cerebral blood flow (rCBF) [2,[10][11][12][13][14][15], which is important for monitoring flow changes. For instance, a study by van Berckel et al [16] observed that longitudinal changes in [ 11 C]PIB standardized uptake value ratio (SUVr) do not reflect changes in specific [ 11 C]PIB binding but rather are secondary to changes in blood flow during the natural course of AD.…”

Binding of the synaptic vesicle radiotracer [11C]UCB-J is unchanged during functional brain activation using a visual stimulation task

“…A similar strategy has been proposed for the β-amyloid radiotracer [ 11 C]PIB, where blood flow measures derived from kinetic modeling are correlated with [ 18 F]FDG uptake in Alzheimer’s disease. 63 Further research is necessary to explore the application of [ 11 C]UCB-J K 1 values as an outcome measure in relation to acute or chronic impairments in brain function.…”