University of Texas System

Other

Clayton Foundation for Research

Wai-hoi Wong

Hongdi Li

Jorge Uribe

Hossain Baghaei

Yuxuan Zhang

Rocio Alicia Ramirez-Jaramillo

Yaqiang Liu

Keri Hicks

Apparatus and methods for optical emission detection comprising scintillating proximal sensors.

Apparatus and methods for optical emission detection

Apparatus and methods for depth-of-interaction (DOI) positron tomography detection are disclosed herein. Certain embodiments utilize dichotomous sensing to obtain DOI information.

Apparatus and methods for depth-of-interaction positron tomography detector using dichotomous sensing

Apparatus and methods comprising a positron emission tomography detector having a first rectangular cross-section crystal block positioned between a first pentagonal cross-section crystal block and a second pentagonal cross-section crystal block.

Apparatus and methods for photosensor quadrant sharing

Systems and methods are described for asymmetrically placed cross-coupled scintillation crystals. A method includes coupling a plurality of photomultiplier tubes to a scintillation crystal array, the scintillation crystal array defining a plurality of corner edges, wherein a first corner edge of the plurality of corner edges is aligned with a first center of a first photomultiplier tube of the plurality of photomultiplier tubes and a second corner edge of the plurality of corner edges is not aligned with a second center of a second photomultiplier tube of the plurality of photomultiplier tubes.

Asymmetrically placed cross-coupled scintillation crystals

Methods and apparatus for tuning scintillation detectors. An output of a first light is equalized with an output of a neighboring, second light. The outputs are measured by one or more light detectors shared by the first and second lights. Outputs of a plurality of light detectors are equalized using the equalized output of the first light.

Methods and apparatus for tuning scintillation detectors

Systems and methods are described for a production method for making position-sensitive radiation detector arrays. A method includes applying a plurality of masks to a plurality of scintillation crystal slabs; coupling the plurality of scintillation crystal slabs to form a sandwich structure; cutting a plurality of slices from the sandwich structure; and coupling at least two of the plurality of slices to form a detector array.

Production method for making position-sensitive radiation detector arrays

Methods and apparatuses for obtaining position and energy information without pileup. Signal integration, which is triggered by a present event, stops when a subsequent event is detected. A weighted value for estimating the total energy in a scintillation is calculated, which includes the energy of the current event and a residual energy from previous events. Remnant correction is used to calculate a pile-up free energy from two consecutive weighted values. An analog filter may be applied to reduce noise. Dynamic digital weighting of integrated values, and/or digital integration may be used during data processing. Pileup can be avoided in conjunction with several types of applications, including multi-zone detector applications and coincidence detection applications. High-resolution timing techniques are also disclosed that facilitate one's ability to avoid pileup.

Method and apparatus to prevent signal pile-up

Systems and methods are described for a positron emission tomography camera with individually rotatable detector modules and/or individually movable shielding sections. An apparatus, includes a detector ring including a plurality of individually movable detector modules. Another apparatus, includes a radiation shield including a plurality of individually moveable shield sections. A method, includes generating an emission image of a sample; generating a transmission image of said sample while generating said emission image of said sample; and then correcting said emission image with said transmission image.

Pet camera with individually rotatable detector modules and/or individually movable shielding sections

Gamma cameras and positron (PET) cameras use scintillation detectors to detect radiation from the body. However, when the number of radiation particles that strike the detector is very high, the chance that signals from two or more individual particles will pile up in the detector (to produce one erroneous, larger signal) is high. This problem is common to all applications using scintillation detectors. The present invention discloses methods and apparatus to prevent and correct for this problem. Results from a circuit according to the present invention show at least a 10 fold improvement in the maximum detection-rate limit over the conventional method.

A PET camera is disclosed with radially translating detector segments coupled with a rotational motion to tailor the camera detector ring to the size of the subject for optimal detection efficiency. In particular methods of using the present invention, the detector segments may be radially translated to describe a small diameter in imaging a small object, such as a breast. Alternately, the detectors may comprise a large diameter to image a large object, such as body. The detector segments may be diametrically opposed for optimal positron detection. The present invention may be coupled with a quadrant-sharing-photomultiplier-detector design.

Tomographic pet camera with adjustable diameter detector ring

A positron emission tomography camera is provided having an array of scintillation crystals placed adjacent other arrays to form an arcuate detection surface surrounding a patient area. Alternatively, the arrays may be placed in a planar configuration on opposing sides of the patient area. Either a three-dimensional image or a two-dimensional image can be formed from a patient's body placed within the patient area. Moreover, the edges between the arrays of crystals are offset in relation to the edges between the light detectors, allowing use of circular photomultiplier tubes instead of the more expensive square photomultiplier tubes. Each light detector is suitably positioned adjacent four adjacent quadrants of four respective arrays to detect radiation emitted from the four quadrants of each array. According to one aspect of the present invention, the crystals within the arrays are selectively polished and selectively bonded to adjacent crystals to present a cross-coupled interface which can tunably distribute light to adjacent light detectors. According to another aspect of the present invention, the crystal arrays are formed by optically bonding slabs of crystals (which may be optically treated for light control) into a 'pre-array' and then cross-cutting the 'pre-array' from one or more sides to form the final array. The grooves may be optically treated, such as with white reflective fillers, for further optical control within the array. In addition, optical jumpers may be coupled to the free end of the array to correct for decoding distortion.

Positron emission tomography camera with quadrant-sharing

The invention relates to methods and apparatus for cameras for gamma radiation, including cameras for positron emission tomography (PET). Included in the invention are cameras having radiation detector arrays splittable into sections, which then may be used to extend the axial field-of-view in a two-dimensional mode. Individual array sections may be equipped with collimators. Additionally, splittable PET cameras having detector arrays approximately one-fourth the diameter of conventional whole-body PET cameras are disclosed as having insertable conformal collimators comprising stacks of planar rings. The inner contours of the planar rings are adapted to accept objects to be imaged in the camera and to closely conform to the objects'surface contours.

High performance positron camera

A positron emission topography camera is provided having an array of scintillation crystals placed adjacent other arrays to form an arcuate detection surface surrounding a patient area. Alternatively, the arrays may be placed in a planar configuration on opposing sides of the patient area. Either a three-dimensional image or a two-dimensional image can be formed from a patient's body placed within the patient area. Moreover, the edges between the arrays of crystals are offset in relation to the edges between the light detectors. Each light detector is suitably positioned adjacent four adjacent quadrants of four respective arrays to simultaneously detect radiation emitted from the four quadrants of each array. Moreover, each crystal within the array is selectively polished and selectively bonded to adjacent crystals to present a cross-coupled interface which can tunably distribute light to adjacent light detectors.

A positron emission tomography camera having a plurality of crystals and planes which are positioned side-by-side and form adjacent rows of crystals transverse to the planes. Each row of each plane has a plurality of crystals and a row of light detectors are positioned adjacent each row of crystals. A row of reflecting masks are positioned between each row of crystals and each row of coacting light detectors and coded for providing an identification to the detectors of which crystal detects radiation. In addition, the ends of the crystals have a frosted finish and the sides have a polished finish for increasing the optical efficiency.

Growing community of inventors

Houston, TX, United States of America

Wai-hoi Wong