Title :
Performance of a coincidence based blood activity monitor
Author :
Moses, William W.
Author_Institution :
Lawrence Berkeley Lab., CA, USA
fDate :
4/1/1990 12:00:00 AM
Abstract :
A novel device has been constructed that measures the positron-emitting radio-tracer concentration in arterial blood by extracting blood with a peristaltic pump and then measuring the activity concentration by detecting coincident pairs of 511-keV photons with a pair of heavy inorganic scintillators attached to photomultiplier tubes. The sensitivity of this device was experimentally determined to be 610 counts/s per μCi/ml, and it has a paralyzing dead time of 1.2 μs, which makes it capable of measuring blood activity concentrations as high as 1 mCi/ml. Its performance is compared to that of two other blood monitoring methods: discrete blood samples counted with a well counter and a device that uses a plastic scintillator to detect positrons directly. The positron detection efficiency of this device for 18 F is greater than that of the plastic scintillation counter, and it also eliminates the radioisotope-dependent correction factors necessary to convert count rate to absolute concentration
Keywords :
biomedical equipment; blood; coincidence techniques; electron detection and measurement; gamma-ray detection and measurement; photomultipliers; radioisotope scanning and imaging; scintillation counters; 1.2 mus; 511 keV; 18F; activity concentration; arterial blood; coincidence based blood activity monitor; coincident pairs; discrete blood samples; inorganic scintillators; paralyzing dead time; peristaltic pump; photomultiplier tubes; plastic scintillator; positron detection efficiency; positron-emitting radio-tracer concentration; well counter; Biomedical measurements; Blood; Isotopes; Monitoring; Plastics; Positron emission tomography; Radiation detectors; Radioactive materials; Solid scintillation detectors; Time measurement;
Journal_Title :
Nuclear Science, IEEE Transactions on
