The present invention relates the system of the correction of energy crosstalk in dual-isotopes simultaneous acquisition (DISA), the system includes a collimator, a metal thin film, a detecting unit, an analyzing unit and a display unit for analyzing energy distribution charts of the dual-isotopes, and using specific equations or artificial neural network methods or independent component analysis to compare the energy distribution charts which are with and without metal thin film The invention uses the metal thin film to remove the energy contamination from dual-isotopes simultaneous acquisition whose photopeak energies are close, the invention effectively separates the energy distribution charts without energy crosstalk, therefore, the system improves diagnostic imaging and relieves patient's discomfort.

A correction image creation device includes: an acquisition unit that acquires at least one original image, which is a basis when creating a correction image used in offset correction with respect to an image that has been obtained by imaging; a determination unit that determines whether or not noise from the exterior is superimposed on the original image; and a cancellation unit that cancels creation of the correction image in a case in which it has been determined by the determination unit that noise from the exterior is superimposed on the original image.

A unit (33) for generating count images for separate energy windows generates main measured count images and auxiliary measured count images on the basis of gamma ray (6) count information measured by a detector head (10). A main measurement window direct ray count rate estimation unit (42) estimates a count rate for direct gamma rays in a main measurement energy window, doing so by subtracting a scattered gamma ray count rate for an auxiliary measurement energy window, which has been estimated from an auxiliary measured count image and detector response data by an auxiliary measurement window scattered ray count rate estimation unit (41), from the main measured count image.

A photon counting circuit, a radiographic imaging apparatus, and a threshold setting method are provided, in which the photon counting circuit is capable of sufficiently reducing a difference between a target threshold value and a threshold value set for a pixel even if each pixel of a photon counting detector is divided into a plurality of subpixels. In the photon counting circuit for counting, for each pixel, electrical charges generated depending on photon energy of radiation applied to an object, a pixel is divided into a plurality of subpixels. When N is a natural number, a threshold value of each of the subpixels is selected from among top N discrete values of a plurality of discrete values arranged in order of proximity to a target threshold value corresponding to the photon energy so as to minimize a difference between the target threshold value and an average of the threshold values of the respective subpixels included in the pixel.

Described is a scintigraphic intracavitary measurement device (100) comprising a supporting rod (10) extending along a main direction of extension (X) and a measuring head (20) coupled or integrated with a first end (10a) of said supporting rod (10). The measuring head (20) comprises at least one collimation element (30) configured to filter gamma radiation emitted by a source (S) defined by a suitably energised body tissue and a scintillation unit (40) configured to detect the gamma radiation emitted by the body tissue and filtered by the collimation element (30). The measuring head (20) is configured to operate with variable investigation areas (A).

A system (10) and a method (150) identify non-functioning pixels in positron emission tomography (PET) imaging. Data describing scintillation events localized to a plurality of pixels (22, 32) of a PET scanner (12) is received. A count map histogram is generated from the received data. The count map histogram maps each of the pixels (22, 32) to a count of scintillation events localized to the pixel (22, 32). One or more non-functioning pixels are identified from the count map histogram.

Methods and systems are provided for performing cathode calibration in a detector assembly. In one embodiment, a method comprises adjusting a cathode bias of a detector based on a total number of events occurring in the detector during a time period while maintaining an anode bias at a desired value, the events corresponding to photon energy detected by the detector. In this way, an automated cathode calibration procedure may be applied to calibrate the detector assembly.

Focusing on a gamma ray detection phenomenon (event) in which a gamma ray from a gamma ray source is Compton scattered at a first-stage detector, the gamma ray is photoelectrically absorbed at a second-stage detector, the spatial distribution of the gamma ray source is imaged within a predetermined image space on the basis of measurement data for the interaction of the detectors and gamma rays. At this time, a probability parameter (v.sub.ij) indicating the probability that Compton-scattered gamma ray arrived from within the image space and a detection sensitivity parameter (s.sub.ij) indicating gamma ray detection sensitivity are set for each event and each pixel on the basis of the measurement data for each event, and these parameters are used to determine the pixel values (.sub.j) for each pixel.

Spatial intensity distributions of scintillation photons emitted by the scintillator array (5) in response to multiple incident gamma rays in record are recorded (S10). Sets of coincidently emitted scintillation photons from the recorded spatial intensity distributions are determined (S22). The sets of coincidently emitted scintillation photons center-of-gravity positions (S24) and cumulative energies are determined (S26). A clustering analysis based on the determined center-of-gravity positions and cumulative energies to obtain clusters (26a, 26b, 33) of gamma ray events attributed to a scintillator array element is performed (15). A cluster (26a, 26b, 33) of the spatial intensity distributions is cumulated (S29) to determine a cumulative spatial intensity distribution of scintillation photons emitted in response to incident gamma rays in the scintillator array element. A light matrix including expected spatial intensity distributions of scintillation photons for different scintillator array elements (15) is determined (S30) based on the cumulative spatial intensity distributions.

A positron emission tomography (PET) system (10) and method (100) classifies gamma events. At least one processor (62, 66, 70) is programmed to receive event data for a plurality of scintillation events corresponding to gamma events. The gamma events are generated by gamma photons from a region of interest (ROI) (14). The gamma events of the event data are classified into a plurality of classifications. The classifications distinguish between single-crystal gamma events and multi-crystal gamma events.