Cross-validation of a non-invasive positron detector to measure the arterial input function for pharmacokinetic modelling in dynamic positron emission tomography. (August 2020)

• Record Type: Journal Article
• Authors: Carroll, Liam; Croteau, Etienne; Kertzscher, Gustavo; Sarrhini, Otman; Turgeon, Vincent; Lecomte, Roger; Enger, Shirin A.
• Is Part Of: Physica medica. Volume 76(2020)
• Page Start: 92
• Page End: 99
• Publication Date: 2020-08
• Subjects: Arterial input function -- Dynamic PET -- Non-invasive detector development -- Scintillation; Medical physics -- Periodicals; Biophysics -- Periodicals; Biophysics -- Periodicals; Imagerie médicale -- Périodiques; Radiothérapie -- Périodiques; Rayons X -- Sécurité -- Mesures -- Périodiques; Physique -- Périodiques; Médecine -- Périodiques; 610.153
• DOI: 10.1016/j.ejmp.2020.06.009
• Languages: English
• ISSNs: 1120-1797

Abstract

Highlights: A non-invasive detector was constructed to measure the arterial input function for dynamic PET. The detector was compared against a microfluidic blood-sampling detector. Scintillating fibers can detect positrons escaping a wrist phantom. Abstract: Kinetic modeling of positron emission tomography (PET) data can assess index rate of uptake, metabolism and predict disease progression more accurately than conventional static PET. However, it requires knowledge of the time-course of the arterial blood radioactivity concentration, called the arterial input function (AIF). The gold standard to acquire the AIF is by invasive means. The purpose of this study was to validate a previously developed dual readout scintillating fiber-based non-invasive positron detector, hereinafter called non-invasive detector (NID), developed to determine the AIF for dynamic PET measured from the human radial artery. The NID consisted of a 3 m long plastic scintillating fiber with each end coupled to a 5 m long transmission fiber followed by a silicon photomultiplier. The scintillating fiber was enclosed inside the grooves of a plastic cylindrical shell. Two sets of experiments were performed to test the NID against a previously validated microfluidic positron detector. A closed-loop microfluidic system combined with a wrist phantom was used. During the first experiment, the three PET radioisotopes 18 F, 11 C and 68 Ga were tested. After optimizing the detector, a second series of tests were performed using only 18 F and 11 C . The maximum pulse amplitude to electronic noise ratio was 52 obtained with 11 C . Linear regressions showed a linear relation between the two detectors. These preliminary results show that the NID can accurately detect positrons from a patient's wrist and has the potential to non-invasively measure the AIF during a dynamic PET scan. The accuracy of these measurements needs to be determined.