Three-dimensional time-of-flight gamma camera system

Patent · Tue Aug 31 04:00:00 EDT 1976

OSTI ID:7349271

Nickles, R J; Meyer, H O

A pair of fast acting elongated plastic scintillation bars are arranged in a skewed spatial relationship to thereby define a unique tetrahedron in space which constitutes the positron sensitive volume of the camera. Each scintillation bar is serviced by a pair of fast acting photomultiplier tubes disposed immediately adjacent the ends of the bars, so that four substantially coincident relative times of activation of the photomultipliers occur when the two opposed 511 keV gamma rays, arising from a positron annihilation within the thetrahedron, happen to hit and be stopped by the two scintillation bars, causing scintillations therein. From measurements and analysis of the various time differences of photomultiplier activations, the location of the respective scintillations along the two bars is defined, thereby defining the gamma ray flight line joining the two scintillations. Measurement and analysis of various time differences of photomultiplier activation then serves to define the point along the gamma ray flight line at which the positron annihilation occurred. In an enhanced sensitivity version, a plurality (p) of pairs of skewed detectors are arranged so that a plurality of detectors are parallel and closely spaced, and the plurality of detectors with which they are paired are also parallel and closely spaced, effectively forming (p/sup 2/) cameras covering (p/sup 2/) tetrahedrons, which tetrahedrons may be closely overlapping as to cover almost identical volumes.

• Assignee: Wisconsin Alumni Research Foundation
• Patent Number(s): US 3978337
• OSTI ID: 7349271
• Country of Publication: United States
• Language: English

Related Subjects

440101* -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
CAMERAS
COINCIDENCE METHODS
CONFIGURATION
COUNTING TECHNIQUES
DESIGN
GAMMA CAMERAS
MEASURING INSTRUMENTS
PLASTIC SCINTILLATION DETECTORS
POSITRON CAMERAS
RADIATION DETECTORS
SCINTILLATION COUNTERS
SOLID SCINTILLATION DETECTORS
TIME-OF-FLIGHT METHOD