155 results about "Pet scanner" patented technology

The invention is directed to a method and apparatus for timing calibration in a PET scanner. According to one embodiment, the invention relates to a method for timing calibration in a PET scanner having a plurality of scintillator blocks. The method comprises: detecting, in a first scintillator block, a first radiation event, wherein the first scintillator block time-stamps the first radiation event; detecting, in a second scintillator block that is adjacent to the first scintillator block, a second radiation event that corresponds to the first radiation event, wherein the second scintillator block time-stamps the second radiation event; and determining a timing characteristic of the first scintillator block with respect to the second scintillator block based on a comparison between the time-stamps of the first radiation event and the second radiation event.

A method for producing a PET image of a tissue using a PET scanner, the scanner comprising a plurality of scintillation crystals (70X / 75X) and a plurality of detectors (71X / 76X). The method comprises forming a first crystal group (160X) including a first subset of the plurality of crystals; forming a second crystal group (164X) including a second subset of the plurality of crystals, wherein crystals comprising the first crystal group (160X) are different from crystals comprising the second crystal group (164X); converting a first beam (120) striking one or more crystals of the first crystal group (70X / 160X) to a first electrical signal (94); converting a second beam striking one or more crystals of the second crystal group (75X / 164X) to a second electrical signal (98), wherein the second beam is scattered from the first beam; determining one or both of a first and a second timing relationship, wherein the first timing relationship (Δt2) is a time interval between a value of the first electrical signal (94) and a time reference (t1), and the second timing relationship (Δt3) is a time interval between a value of the second electrical signal (98) and the time reference (t1); correcting the second electrical signal (98) to produce a corrected second electrical signal using a correction factor derived from at least one of the first and the second timing relationships to compensate for energy in the second signal scattered from the first signal; and creating an image of the tissue (12) using the corrected second electrical signal.

A tomography scanner has intentionally designed, well defined gaps between detector rings with image reconstruction obtained with the use of conventional tomography data processing. The scanner is particularly advantageous as a small animal PET scanner.

Provided are new methods for enhancing the selection of true (T) annihilation events relative to the inclusion of true scattered (TS) and random (R) annihilation events in PET tomographs and thereby improving the sensitivity and / or resolution of PET scanners. The methods include reconstruction of Compton scattering interactions in the γ-ray detectors for determining the angles of incidence of the γ-rays received at the detectors and may utilize γ-ray polarization effects and electron recoil data associated with positron annihilation and Compton scattering. The use of the γ-ray polarization effects provides an improved ability for selecting data corresponding to T events while simultaneously suppressing data corresponding to TS and R events during PET applications.

Systems and methods for data reading, which in one configuration is directed to an automated optical code data reader (5) in the form of a tunnel or portal scanner (100, 500) having an open architecture configured with front and rear inverted U-shaped arches (110, 120), a plurality cameras (some or most of which having multiple fields of view) (150, 160, 170, 180, 192 / 194, 250, 260, 270, 280, 300, 310, 320, 330) in each of the arches for reading the top five sides of an item (20) being passed by a conveyor (15 / 16) through a read region formed by the arches, and a bottom reader (130) including one or more cameras (410, 420) under the conveyor for reading a bottom side of the item through a gap (50) in the conveyors as the item is passed over the gap. Also disclosed are specific imaging schemes for providing effective views of the items with a minimum number of cameras.

In a method and apparatus for identifying regions of interest in medical images of a subject, in particular images captured by a medical imaging apparatus, such as a PET scanner, a list of voxels of the image is obtained, and sorted according to a first variable. A user-selection of an initial voxel in the image is then registered, and at least one voxel or group of voxels from the sorted list is selected as a region of interest, according to a property of the at least one voxel or group in relation to the user-selected initial voxel. The image may be pre-processed to generate the sorted list of voxels, following which the user selection of the initial voxel is registered.