摘要:
Large-area, flat-panel photo-detectors with sub-nanosecond time resolution based on microchannel plates are provided. The large-area, flat-panel photo-detectors enable the economic construction of sampling calorimeters with, for example, enhanced capability to measure local energy deposition, depth-of-interaction, time-of-flight, and/or directionality of showers. In certain embodiments, sub-nanosecond timing resolution supplies correlated position and time measurements over large areas. The use of thin flat-panel viewing radiators on both sides of a radiation-creating medium allows simultaneous measurement of Cherenkov and scintillation radiation in each layer of the calorimeter. The detectors may be used in a variety of applications including, for example, medical imaging, security, and particle and nuclear physics.
摘要:
Large-area, flat-panel photo-detectors with sub-nanosecond time resolution based on microchannel plates are provided. The large-area, flat-panel photo-detectors enable the economic construction of sampling calorimeters with, for example, enhanced capability to measure local energy deposition, depth-of-interaction, time-of-flight, and/or directionality of showers. In certain embodiments, sub-nanosecond timing resolution supplies correlated position and time measurements over large areas. The use of thin flat-panel viewing radiators on both sides of a radiation-creating medium allows simultaneous measurement of Cherenkov and scintillation radiation in each layer of the calorimeter. The detectors may be used in a variety of applications including, for example, medical imaging, security, and particle and nuclear physics.
摘要:
A device and method used in the high resolution Positron Emission Tomography (PET) systems for digitizing radiation events for a scintillation camera and a data acquisition system. The device comprises a scintillation digitizer, including a plurality of comparators and amplifiers, two ADCs, and an analyzer for resolving the digital values of radiation events. The method comprises comparing a plurality of analog electric pulses generated upon radiation event detections with a reference voltage corresponding to an energy level of interest, amplifying all of the signals with two groups of coefficients, summing the two groups of amplified signals, digitizing the summed signals, and analyzing the digitized sums to determine digital values corresponding to a plurality of the radiation events.
摘要:
A device and method used in high resolution positron emission tomography (PET) systems for digitizing gamma ray energy and characterizing peak time and decay time constant, models a voltage pulse generated upon a PET event detection as a fast linearly rising edge followed by a slower exponential decay. The model includes parameters of the voltage pulse that are relevant for PET event detection including a decay constant, a peak voltage value, and a peak time, which are determined from time interval measurements of the voltage pulse. The time interval measurements are made using comparators and counters in an exemplary electronic implementation.
摘要:
A device and method used in the high resolution Positron Emission Tomography (PET) systems for digitizing radiation events for a scintillation camera and a data acquisition system. The device comprises a scintillation digitizer, including a plurality of comparators and amplifiers, two ADCs, and an analyzer for resolving the digital values of radiation events. The method comprises comparing a plurality of analog electric pulses generated upon radiation event detections with a reference voltage corresponding to an energy level of interest, amplifying all of the signals with two groups of coefficients, summing the two groups of amplified signals, digitizing the summed signals, and analyzing the digitized sums to determine digital values corresponding to a plurality of the radiation events.
摘要:
A device and method used in high resolution positron emission tomography (PET) systems for digitizing gamma ray energy and characterizing peak time and decay time constant, models a voltage pulse generated upon a PET event detection as a fast linearly rising edge followed by a slower exponential decay. The model includes parameters of the voltage pulse that are relevant for PET event detection including a decay constant, a peak voltage value, and a peak time, which are determined from time interval measurements of the voltage pulse. The time interval measurements are made using comparators and counters in an exemplary electronic implementation.
摘要:
A method and apparatus are provided for reconstructing images from data obtained from scintillation events occurring within a projection space of a depth-of-interaction positron emission tomography system. The method includes the steps of identifying a segment of each depth-of-interaction detector of respective pairs of depth-of-interaction detectors detecting the scintillation-events of the data obtained within the projection space and estimating a set of sinograms from the data based upon a set of depth-independent point spread functions of the identified segments of the respective pairs of depth-of-interaction detectors.
摘要:
In some embodiments, an image-guided radiotherapy apparatus and method is provided in which a radiotherapy radiation source and a gamma ray photon imaging device are positioned with respect to a patient area so that a patient can be treated by a beam emitted from the radiotherapy apparatus and can have images taken by the gamma ray photon imaging device. Radiotherapy treatment and imaging can be performed substantially simultaneously and/or can be performed without moving the patient in some embodiments. The gamma ray photon imaging device can be coupled and movable with respect to any part of a building structure, can be located on a portable frame movable to and from the radiotherapy radiation source and patient, or can take other forms. In some embodiments, the gamma ray photon imaging device can be used for imaging in connection with other types of medical interventions.
摘要:
A method and system for the computerized registration of radionuclide images with radiographic images, including generating image data from radiographic and radionuclide images of the thorax. Techniques include contouring the lung regions in each type of chest image, scaling and registration of the contours based on location of lung apices, and superimposition after appropriate shifting of the images. Specific applications are given for the automated registration of radionuclide lungs scans with chest radiographs. The method in the example given yields a system that spatially registers and correlates digitized chest radiographs with V/Q scans in order to correlate V/Q functional information with the greater structural detail of chest radiographs. Final output could be the computer-determined contours from each type of image superimposed on any of the original images, or superimposition of the radionuclide image data, which contains high activity, onto the radiographic chest image.
摘要:
In some embodiments, an image-guided radiotherapy apparatus and method is provided in which a radiotherapy radiation source and a gamma ray photon imaging device are positioned with respect to a patient area so that a patient can be treated by a beam emitted from the radiotherapy apparatus and can have images taken by the gamma ray photon imaging device. Radiotherapy treatment and imaging can be performed substantially simultaneously and/or can be performed without moving the patient in some embodiments. The gamma ray photon imaging device can be coupled and movable with respect to any part of a building structure, can be located on a portable frame movable to and from the radiotherapy radiation source and patient, or can take other forms. In some embodiments, the gamma ray photon imaging device can be used for imaging in connection with other types of medical interventions.