221 results about "Nuclear medicine imaging" patented technology

Semiconductor radiation detectors are cooled to improve accuracy in radiation detection. Semiconductor radiation detectors are cooled by heat conductance through heat conductive boards. In addition, the semiconductor radiation detectors are cooled by cooling medium filled or supplied to a heat insulating body covering the semiconductor radiation detectors.

A hybrid medical imaging system comprises a nuclear medicine imaging subsystem for capturing an image of a target region of a subject, a magnetic resonance imaging (MRI) subsystem for capturing an MRI image of the target region based on at least one MRI parameter and processing structure communicating with the subsystems. The processing structure processes the MRI image to estimate attenuation within the target region and uses the estimated attenuation to correct the image captured by the nuclear medicine imaging subsystem.

According to the present invention, a novel slat collimator for use in nuclear medicine imaging is provided. The slat collimator comprises a first layer comprising a plurality of spaced apart elongated slats and a second layer comprising a plurality of spaced apart elongated slats. The slats of the second layer are positioned orthogonally with respect to the slats of the first layer. The slats are constructed of a radiation attenuation material and the spaces between the slats may be non-variable or variable.

A medical examination device for CT imaging and for nuclear medical imaging is provided. The medical examination device has an essentially ring-shaped gantry with a CT imaging arrangement and a nuclear medical imaging arrangement. The gantry has an especially laterally arranged, fold-out or removable segment for creating an access opening to the interior of the gantry.

A Nuclear Medicine (NM) imaging system and method using multiple types of imaging detectors are provided. One NM imaging system includes a gantry, at least a first imaging detector coupled to the gantry, wherein the first imaging detector is a non-moving detector, and at least a second imaging detector coupled to the gantry, wherein the second imaging detector is a moving detector. The first imaging detector is larger than the second imaging detector and the first and second imaging detectors have different detector configurations. The NM imaging system further includes a controller configured to control the operation of the first and second imaging detectors during an imaging scan of an object to acquire Single Photon Emission Computed Tomography (SPECT) image information such that at least the first imaging detector remains stationary with respect to the gantry during image acquisition.

A pinhole collimator is provided that eliminates or at least minimizes the need for collimator exchange, to manage system sensitivity versus spatial resolution tradeoff, and to control imaging FOV (field of view) depending on object size by controlling the focal length of the collimator. There is also provided a detector system is that includes a detector, a collimator, and means for changing the focal length. Various means for changing the focal length are also identified. The collimator can have a plurality of apertures in a top plate, each aperture with its own collimator septa. Additionally, there is provided a medical imaging system that includes the detector system and collimator of the present invention. The nuclear medical imaging systems can have a hand-held detector assembly and be portable.

A method of examining a patient is provided. The method includes imaging a patient utilizing a computed tomography imaging modality, the patient between the pencil-beam x-ray source and the x-ray detector, and imaging the patient between the pencil-beam x-ray source and the x-ray detector using a nuclear medicine imaging modality.

A multi-pinhole collimator nuclear medical imaging detector divides a target object space into many non-overlapping areas and projects a minified image of each area onto a segmented detector, where each segment functions as an independent detector or imaging cell. Septa may be provided between the collimator and the detector, to physically isolate the segments.

The invention discloses a multi-gamma-photo simultaneous medicine emission time coincidence nuclear medical imaging system and method, and belongs to the field of nuclear medical images. The system comprises multiple detector probes arranged in non-parallel mode, a time coincidence module and a computer platform. Each detector probe is composed of a collimator and a gamma photo detector with a time measuring function. Multiple gamma photos radiated by detection radionuclides within a short time form multiple gamma-photo coincidence events. The point with the smallest sum, of distances of projection lines determined by the multiple gamma-photo coincidence events, calculated by the method is the disintegration position of radionuclides, and the distribution of radionuclides in living bodies can be obtained by accumulating a certain number of mult-gamma-photo coincidence events. By means of the imaging system and method, reconstruction algorithm is simplified, the signal to noise ratio of reconstructed images is improved, the requirement for the gamma photo total count is lowered, and the irradiation risk to patients is lowered.

A customizable and upgradable imaging system is provided. Imaging detector columns are installed in a gantry to receive imaging information about a subject. Imaging detector columns can extend and retract radially as well as be rotated orbitally around the gantry. The gantry can be partially populated with detector columns and the detector columns can be partially populated with detector elements. The system can automatically adjust an imaging operation based on installation information related to partial population or other factors such as scan type or subject specific information. This system can be a Nuclear Medicine (NM) imaging system to acquire Single Photon Emission Computed Tomography (SPECT) image information.

Systems and methods for attenuation compensation in nuclear medicine imaging based on emission data are provided. One method includes acquiring emission data at a plurality of energy windows for a person having administered thereto a radiopharmaceutical comprising at least one radioactive isotope. The method also includes performing a preliminary reconstruction of the acquired emission data to create one or more preliminary images of a peak energy window and a scatter energy window and determining a body outline of the person from at least one of the reconstructed preliminary image of the peak energy window or of the scatter energy window. The method further includes identifying a heart contour and segmenting at least the left lung. The method additionally includes defining an attenuation map based on the body outline and segmented left lung and reconstructing an image of a region of interest of the person using an iterative joint estimation reconstruction.

The DCC (Data Consistency Condition) algorithm is used in combination with MLAA (Maximum Likelihood reconstruction of Attenuation and Activity) to generate extended attenuation correction maps for nuclear medicine imaging studies. MLAA and DCC are complementary algorithms that can be used to determine the accuracy of the mu-map based on PET data. MLAA helps to estimate the mu-values based on the biodistribution of the tracer while DCC checks if the consistency conditions are met for a given mu-map. These methods are combined to get a better estimation of the mu-values. In gated MR/PET cardiac studies, the PET data is framed into multiple gates and a series of MR based mu-maps corresponding to each gate is generated. The PET data from all gates is combined. Once the extended mu-map is generated the central region is replaced with the MR based mu-map corresponding to that particular gate. On the other hand, in dynamic PET studies the uptake in the patient's arms reaches a steady state only after the tracer distributes throughout the body. Hence, for dynamic scans, the projection data of all frames is summed and used to generate the MLAA based extended mu-map for all frames.

Methods and systems for positioning detectors for Nuclear Medicine (NM) imaging are provided. One system includes a gantry supporting one or more imaging detectors, wherein the gantry has a portion configured for movable operation. The system also includes a table on one side of the gantry configured to support a patient thereon, wherein the table is further configured to move within an opening of the gantry. The system further includes a patient support device movably positioned on an opposite side of the gantry from the table, wherein the patient support device is configured for movable operation.

Collimators and methods for manufacturing collimators for nuclear medicine (NM) imaging systems are provided. One method includes forming a plurality of collimator segments from powdered tungsten, wherein the plurality of collimator segments have opposing faces with edges therebetween. The method also includes sintering the powdered tungsten segments and joining the plurality of sintered powdered tungsten segments at least at one or more of the edges to form the collimator for the NM imaging system.

The present invention provides a nuclear medicine imaging apparatus and image data generation method that achieves restarting of the generation of projection data and at an early stage while monitoring a variation of count values for detecting an occurrence of non-permissible body movement of a patient. The image processing apparatus consistent with the present invention detects a pair of gamma-rays successively emitted from an object with a radioactive isotope through a pair of detector modules in a data detecting unit. A data processing unit and an incident direction calculating unit in the image processing apparatus respectively calculate a gamma-ray detection position and a gamma-ray incident direction based on the acquired detection signals. A projection data generating unit in the apparatus generates monitoring projection data based on each count value of the detection signals in correspondence to the gamma-ray detection position and the gamma-ray incident direction. A projection data monitoring unit calculates a body movement index of the object by comparing count values of the monitoring projection data that are generated in each of two preferably adjoining monitoring periods. A system control unit generates an alarm signal for performing repetition of the monitoring projection data when the body movement index exceeds a threshold value and displays the alarm signal on a display unit.

The invention relates to a respiration correction technique in positron emission tomography, in particular to a technique for correcting the artifact of respiration tomography on the basis of the sensitivity characteristics of a three-dimensional positron emission detector, belonging to the field of nuclear medical tomography. The correction method provided by the invention can effectively compensate for the image artifact caused by respiration, thereby improving the diagnostic accuracy of doctors. The correction method comprises the following steps: frame segmentation is carried out on the acquired dynamic data by using the variation characteristics of the geometric sensitivity of a scanning detector in the three-dimensional PET, wherein the number of intra-frame photons can reflect the phase position of the organ motion, and the number of photons of each phase position has a linear relation with the motion displacement thereof; accordingly, each phase position is moved to certain reference phase position point for correcting; and the image reconstructed at last constitutes the image artifact caused by the respiration in the PET improved by correction. Compared with the prior art like the gating correction technique, the method of the invention dispenses with hardware equipment and extra preparation by patients or clinic before scanning, therefore, the method is easier, more effective and more reliable in actual application.

Emission contamination data are collected in a shifted mock scan simultaneous with the collection of transmission data during a transmission scan of a patient with a collimated gamma point source, the transmission data are corrected with the emission contamination data, and the corrected transmission data are used for attenuation correction of emission data for reconstruction of an emission image of the patient. In a preferred implementation, when the point source is at a particular axial location and illuminates an axial beamwidth of “Fz” over the gamma detector, emission contamination data are collected from the gamma detector over an axial separated region “Fz′” having about the same axial extent but axially displaced by about half of the axial field of view (FOV).

A detector is provided for nuclear medicine imaging. Scintillator pixels form an axial array and a transaxial array. A first photosensor is positioned along the axial array; and a second photosensor is positioned along the transaxial array, wherein the first photosensor and the second photosensor provide dual event localization for nuclear medicine imaging.