Method and apparatus for determining depth of interactions in a detector for three-dimensional complete body screening

Abstract

The present invention is directed to a system and method for efficiently and cost effectively determining an accurate depth of interaction for a crystal that may be used for correcting parallax error and repositioning LORs for more clear and accurate imaging. The present invention is directed to a detector assembly having a thin sensor (e.g., APD) deployed in front of the detector (the side where the radioactive source is located and the photon is arriving to hit the detector) and a second sensor (APD or photomultiplier) on the opposite side of the detector. The light captured by the two interior and exterior sensors which is proportional to the energy of the incident photon and to the distance where the photon was absorbed by the detector with respect to the location of the two sensors, is converted into an electrical signal and interpolated for finding the distance from the two sensors which is proportional to the location where the photon hit the detector.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to radiation detectors. More particularly, the present invention relates to a system and method for correcting parallax error in a detector resulting from inaccurately assessing where the photon interacted with the detector, and thereby increasing efficiencies of traditional Positron Emission Tomography (PET) devices on a photons per unit of radiation basis. 2. Description of Related Art These devices (detectors) are about 200 times smaller than the large detectors for high-energy physics and require identification of only one particle, the photon. The task to be solved of capturing and identifying the particles is relatively easier than before: one particle instead of five on a detector 200 times smaller. The use of positron emissions for medical imaging has been well document from the early 1950's, see “A History of Positron Imagining,” Brownell, Gordon, presented on Oct. 15, 1999, Massachuset...

AI Technical Summary

Benefits of technology

The present invention is directed to a system and method for efficiently and cost effectively determining an accurate depth of interaction for a crystal that may be used for correcting parallax error and repositioning LORs for more clear and accurate imaging. The present invention is direct to a detector assembly having. A thin sensor (e.g. Avalanche Photodiode (APD)) is deployed in front of the detector (side where the radioactive source is located and the photon is arriving to hit the detector) and a second sensor (APD or photomultiplier) on the opposite side of the detector. The light captured by the two sensors interior sensor and exterior sensor, which is proportional to the energy of the incident photon and to the distance where the photon was absorbed by the detector with respect to the location of the two sensors, is converted into electrical signal and interpolated for finding the distance from the two sensors, which is proportional to the location where the photon hit the detector.

Problems solved by technology

While particle detection in high energy physics and medical imaging have some common ground, differences between the disciplines are sticking.

However, although the price and performance of the systems from the different manufactures are comparable, one manufacturer's system (Siemens) uses nearly ideal crystal detectors, while contrastingly, the other manufacturer's system (General Electric) uses cheaper, lower quality crystal detectors with slower decay time.

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