Characterization of scintillating fibers for use as positron detector in positron emission tomography.
Phys Med 2019;
65:114-120. [PMID:
31450121 DOI:
10.1016/j.ejmp.2019.08.009]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/15/2019] [Accepted: 08/11/2019] [Indexed: 10/26/2022] Open
Abstract
PURPOSE
Manual and automatic blood sampling at different time intervals is considered the gold standard to determine the arterial input function (AIF) in dynamic positron emission tomography (PET). However, blood sampling is characterized by poor time resolution and is an invasive procedure. The aim of this study was to characterize the scintillating fibers used to develop a non-invasive positron detector.
METHODS
The detector consists of a scintillating fiber coupled at each end to transmission fiber-optic cables that are connected to photo multiplier tubes in a dual readout setup. The detector is designed to be wrapped around the wrist of the patient undergoing dynamic PET. The attenuation length and bending losses were measured with excitation from gamma radiation (137Cs) and ultraviolet (UV) light. The response to positron-emitting radio-tracers was evaluated with 18F and 11C.
RESULTS
The attenuation length for a 3.0 m and 1.5 m long scintillating fiber both coincides with the attenuation length given by the manufacturer when excited with the 137Cs source, but not with the UV source due to the differences in scintillation mechanisms. The bending losses are smaller than the measurement uncertainty for the 137Cs source irradiation, and increase when the bending radius decrease for the UV source irradiation. The signal-to-noise ratio for 18F and 11C solutions are 1.98 and 22.54 respectively. The measured decay constant of 11C agrees with its characteristic value.
CONCLUSION
The performed measurements in the dual readout configuration suggest that scintillating fibers may be suitable to determine the AIF non-invasively.
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