49 results about "Positron emission tomography scanner" patented technology

A method and apparatus for increasing the resolution of a Positron Emission Tomography scanner. The method and apparatus comprise elements and acts for centering a region of interest of an object at a point between first and second detector arrays which is at least about ten percent closer to the first detector array than to the second detector array.

The invention relates to a positron emission tomography scanner and a conformity judgment and selection method. The scanner comprises a plurality of detectors. The method comprises the following steps: acquiring instance information of each detector; storing the instance information in the corresponding storage space; taking the time information of each instance information as address information of the storage space; acquiring a plurality of sign information according to each instance information, wherein each sign information shows times of detecting gamma photons in corresponding time; acquiring judgment and selection information according to each sign information, wherein the judgment and selection information represents the times of detecting the gamma photons in a preset conformed time window from the corresponding time information; ranking each judgment and selection according to the corresponding time information; checking the ranked judgment and selection information by utilizing sequence checking features in sequence; identifying the storage space that the conformed instance corresponds to; and outputting the instance information in the storage space that the conformed instance corresponds to. The positron emission tomography scanner and the conformity judgment and selection method provided by the invention have the advantages of rapid and efficient conformity judgment and selection and wide application range.

The invention relates to a detector arrangement (21) for a tomographic imaging apparatus, particularly for a positron emission tomograph. The detector arrangement (21) according to the invention includes at least two sandwiched pairs of a scintillator (22-24) and an associated photodetector (25-27), wherein the pairs are sandwiched along a direction of detection.

A method for calibrating a positron emission tomography scanner of a radiation therapy device is provided. The method includes applying at least one defined radiation dose in a sample body; measuring the activity generated by the radiation dose using the positron emission tomography scanner; and calibrating the positron emission tomography scanner based on the measured activity.

The invention relates to a positron emission tomography scanner and a coincidence judging and selecting method therein. The positron emission tomography scanner comprises a detecting ring, wherein the detecting ring consists of a plurality of detectors. The coincidence judging and selecting method comprises the following steps of: judging whether each detector is correlated to opposite detectors, acquiring correlation data according to each judgment result, and judging the two detectors to be correlated to each other if a time difference of a single event respectively detected by the two detectors stays within a coincidence time window, wherein the opposite detectors of any detector refer to the detectors in a sector area with a preset angle by adopting the detector as a center; and judging whether the two detectors are exclusively correlated to each other according to the correlation data and judging the single event detected by the two exclusively-correlated detectors to be a coincidence event. The positron emission tomography scanner and the coincidence judging and selecting method have advantages of rapidness in coincidence judging and selection, high efficiency and wide application range.

The invention discloses a cooling system of a positron emission tomography scanner. The positron emission tomography scanner comprises a peripheral electronics plate, a detector module and a bottom electronics plate; the cooling system comprises a cooling device, a peripheral cooling air channel, an inner chamber cooling air channel and a bottom cooling air channel; the inner chamber cooling air channel is a chamber body and comprises an air inlet channel and an air return channel; the peripheral electronics plate is located in the peripheral cooling air channel; the detector module is located between the air inlet channel and the air return channel; the bottom electronics plate is located in the bottom cooling air channel; the cooling device is used for conveying cooled air flow to the peripheral cooling air channel, the inner chamber cooling air channel and the bottom cooling air channel so as to cool the peripheral electronics plate, the detector module and the bottom electronics plate. According to the cooling system of the positron emission tomography scanner, ventilation cooling is performed on the peripheral electronics plate and the bottom electronics plate, the low-temperature and stable inner chamber cooling air channel is provided for the detector module, and accordingly the stability and the imaging quality of the system are improved.

A light receiver for detecting incident time is installed on the side of a radiation source of a scintillator (including a Cherenkov radiation emitter), and information (energy, incident time, an incident position, etc.) on radiation made incident into the scintillator is obtained by the output of the light receiver. It is, thereby, possible to identify an incident position and others of radiation into the scintillator at high accuracy.

The invention relates to a clock synchronization control method, a clock synchronization control system and a positron emission tomography scanner. The clock synchronization control system comprises a coincidence processing module CPM and a plurality of continuous sampling modules CSM respectively connected with the coincidence processing module, wherein the coincidence processing module is used for fanning local crystal oscillators, as source clocks, out through multiple routes, correspondingly sending multiple routes of fan-out clock data to each continuous sampling module and receiving, judging and selecting example data sent by each continuous sampling module; each continuous sampling module is used for receiving the multiple routes of clock data sent by the coincidence processing module, recovering the source clocks according to the received clock data, taking the recovered clock as main working clock sampling example data and sending the collected example data to the coincidence processing module. According to the clock synchronization control system, bidirectional data transmission is realized between the continuous sampling modules and the coincidence processing module, a global clock module does not need to be singly arranged, and the global clock distribution of each continuous sampling module is realized through the coincidence processing module, so that the system structure is simplified.

The invention provides a positron emission tomography apparatus and a nuclear medical image generating method. In a case that a gamma ray has entered into a plurality of scintillators adjacent to each other simultaneously, a detector detects the gamma ray having entered simultaneously. A position calculator calculates the ratio of wave heights representing the energies of the detected gamma ray. The position calculator obtains a trajectory of such a gamma ray that a ratio of distances passed by the gamma ray inside the plurality of scintillators, respectively, coincides with the ratio of the wave heights. The position calculator obtains an intersection between the boundary of the plurality of scintillators and the trajectory, as a passing position of the gamma ray. A reconstructing part executes a back projection process with the trajectory passing through the calculated passing position as a projection position.

Detector efficiency data is generated for a positron emission tomography scanner (2) including a single photon source by conducting a blank scan acquisition procedure using the single photon source. The acquired detection count data is processed using an efficiency estimation algorithm to calculate data efficiencies of individual detectors in the detector array (8). In one embodiment, the detection count data is output as artificial coincidence count data and the efficiency estimation algorithm operates on the artificial coincidence count data. The method can be used in a non-rotating scanner or a rotating scanner.

The method calculates a scatter estimate for scatter correction of detection data from a subject in a positron emission tomographic scanner. The detection data represent the scattered events and unscattered events of annihilation photons emitted in the subject. The method uses the following steps:

• • determine an estimate of the unscattered events;
  • determine a simulation of the scattered events;
  • determine a value of a scaling factor by fitting the sum of the estimate of the unscattered events and a product of the scaling factor and the simulation of the scattered events to the detection data; and
  • determine the scatter estimate as the product of the scaling factor having said value and the simulation of the scattered events.

A positron emission camera comprising a plurality of scintillators, wherein the scintillators comprise LuAlO3:Ce (LuAP) based crystals (18,20). In particular, the scintillation crystals (18,20) are LuAP and/or LuYAP.

A method is disclosed for determining radiation attenuation as a result of an object in a positron emission tomography scanner. In at least one embodiment, a phantom object is arranged in the positron emission tomography scanner during the method. First raw radiation data of the phantom object is acquired while the object is not arranged in the positron emission tomography scanner. A first image of the phantom object is calculated from the first raw radiation data. The object then is arranged in the positron emission tomography scanner (2) and preliminary radiation attenuation of the object is identified. Second raw radiation data of the phantom object is acquired while the object is arranged in the positron emission tomography scanner. A second image of the phantom object is calculated from the second raw radiation data taking into account the preliminary radiation attenuation. The radiation attenuation is determined on the basis of the first image and the second image.

A positron emission tomography (PET) system is provided. The system includes a first detector panel including a first array of detectors, a second detector panel including a second array of detectors, said second detector panel being moveable relative to a point between the first detector panel and the second detector panel, a tracking system configured to detect a position of said second detector panel relative to the first detector panel while imaging a subject, a computing device in communication with the first detector panel, the second detector panel, and the tracking system, the computing device configured to receive coincidence data from the first and second detector panels, receive position data from the tracking system, wherein each coincidence datum of the received coincidence data is associated with a unique position datum of the received position data, and reconstruct a plurality of images based on the received coincidence data and the received position data.

Positron emission tomography, possibly in combination with computed tomography, allows in addition to medical diagnostic imaging the quantitative determination of various parameters. Quantitative measurements using tomographs exhibit a severe and unavoidable dependency on the imaging properties of the respective tomograph, which makes quantitative assessment of the results difficult. This relates particularly to multicentric medical studies, which obligatorily require quantitative comparability of the data measured by the participating centers. The methods claimed herein include the definition of a virtual tomograph with defined imaging properties. The claimed methods also cover determination of the imaging properties of different tomographs on the basis of suitable reference measurements and possibly by using a calibration phantom. Based on the definition of the virtual tomograph and the determination of the imaging properties of different tomographs, the methods according to the invention then allow conversion and subsequently standardized and quantitatively comparable representation of the image data recorded by the different tomographs or systems as if all measurements were acquired equally by the virtual system. The method according to the invention therefore supports the quantitative evaluation of image data in multicentric studies.

A portable positron emission tomography (PET) scanner includes a rotatable scan detector ring which can be rotated 90 degrees for imaging a patient in a vertical or horizontal orientation. In the vertical orientation, a patient can be standing or seating such that the aperture of the scan detector ring is raised to allow the patient to be within the scanning region and lower to perform the image scanning on the patient. In the horizontal orientation, a patient must be lying down on a platform whereby the platform is moved within the aperture of the scan detector ring to perform the image scanning on the patient. In this horizontal orientation, the scan detector ring is also stowed and secured to be moved to other scanning locations.