G01N2223/3035

Spectral calibration of spectral computed tomography (CT)

There is set forth herein a method including performing with an X-ray detector array of a CT imaging system one or more calibration scans, wherein the one or more calibration scans include obtaining for each element of the first through Nth elements of the X-ray detector array one or more calibration measurements; and updating a spectral response model for each element of the first through Nth elements using the one or more calibration measurements. In another aspect, a CT imaging system can perform imaging, e.g. including material decomposition (MD) imaging, using updated spectral response models for elements of an X-ray detector array. The spectral response models can be updated using a calibration process so that different elements of an X-ray detector array have different spectral response models.

Calibration Method and Device Therefor

A method of determining at least one x-ray scanning system geometric property includes the steps of positioning a calibration device inside a scanning chamber of the scanning device, the chamber being intersected by at least one fan beam of x-rays during a scanning operation, measuring a distance between the calibration device and at least one inner wall of the chamber, scanning the calibration device to produce an image of the calibration device, identifying pixels representing the a geometric feature of the calibration device in the image, determining a position and orientation of the pixels representing the geometric feature in the image and, determining a scanning system property based on the position and orientation of the pixels representing the geometric feature in the image. The position and orientation of the feature in the scanning chamber and the x-ray scanning system property may be determined simultaneously.

Artefact for evaluating the performance of an X-ray computed tomography system

The invention provides a kit for assembly of an artifact for evaluating performance purposes of an X-ray CT metrology system. The artifact comprises one or more interconnectable, stackable support plates, onto which a plurality of spherical bodies is mounted. The lightweight stacked support plate structure allows for a plurality of different configurations, and can be disassembled for enhanced storage, and safe and compact transportation.

Calibration hardware phantom for differential phase contrast imaging

A phantom body (PB) for use in a differential phase contrast imaging apparatus (IM) for calibration of same. The phantom body (PB) allows for simultaneous calibration of three different image signal channels, namely refraction, phase shift and small angle scattering.

PHANTOM DEVICE, DARK FIELD IMAGING SYSTEM AND METHOD FOR ACQUIRING A DARK FIELD IMAGE
20190298294 · 2019-10-03 ·

The present invention relates to phantom device for a dark field imaging system. Although dark field imaging is known to be sensitive to changes in the micro-structure of the tissue of a human subject that may be caused during a disease progression, there may be a need to quantify information provided by an image of the human subject. A detector signal component representing the dark field image may be altered by changes of the X-ray spectrum which passes tissue of the human subject comprising micro-structures. This may be caused due to an attenuation of the X-ray radiation previously provided by an X-ray source, wherein the attenuation may be caused by tissue of the human subject, which covers said micro-structure comprising tissue. In order to provide information in clinical practice regarding the influence of attenuation to the X-ray radiation before it passes the micro-structure issue of the human subject, the phantom device for dark field imaging is proposed. The phantom device comprises a main body, wherein the main body comprises a plurality of reference parts. Each of the reference parts comprises an attenuation part and a de-coherence part. The attenuation part and the de-coherence part of the same reference part are stacked on top of each other. As a result, the different reference parts may imitate different portions of the human subject extending along a propagation direction of an X-ray radiation, which is propagated from an X-ray source of the dark field imaging system towards the corresponding X-ray detector. Thus, if the phantom device is scanned simultaneously or subsequently with the human subject, a dark field image may be acquired, which represents the human subject as well as the phantom device. From the image parts of the dark field image caused by the phantom device, a clinician may assess and classify the corresponding parts of the image, which relates to the human subject, for instance to the portions of the lung. The present invention further relates to an imaging system configured to scan a human subject together with the phantom device as well as a corresponding method.

COMPUTED TOMOGRAPHIC SYSTEM CALIBRATION
20190302036 · 2019-10-03 ·

Method and apparatus are provided for calibration or verification of accuracy specification of a computed tomographic system. In one embodiment, the apparatus can include a base structure, a first set of test objects arranged along a first axis and coupled to the base structure, and a second set of test objects arranged along a second axis and coupled to the base structure. The first set of test objects and the second set of test objects have a first geometry. The apparatus can also include a third set of test objects and a fourth set of test objects. The third set of test objects, and the fourth set of test objects have a second geometry different from the first geometry. Locations of the first, second third and fourth set of test objects are spatially fixed with respect to the base structure. The apparatus is a test specimen adapted for calibration or accuracy verification of computed tomography system.

METHOD FOR CALIBRATING AN X-RAY MEASURING FACILITY
20190175137 · 2019-06-13 · ·

A method is for calibrating an X-ray measuring facility. The method includes preparing the facility for measurement for a resolution of a plurality of different energy intervals; positioning a test object in a beam path of an X-ray beam; irradiating the test object via the X-ray beam, and during the irradiating, an intensity measurement of the test object appropriately resolved according to the energy intervals is carried out by the facility; determining an absorption function of the test object using the intensity measurement; preparing one of the energy intervals as a reference interval such that the absorption function has a negligible energy dependency over the reference interval; determining a correction function of the absorption function, for at least one further energy interval of the energy intervals, using at least one value of the absorption function in the reference interval; and calibrating the facility using the correction function determined.

X-ray automated calibration and monitoring

A scanner comprises an electromagnetic wave source; a collimator positioned to alter the electromagnetic waves emitted from the electromagnetic wave source into an electromagnetic beam; and a detector positioned to measure one or more levels of electromagnetic energy of the electromagnetic beam, wherein a collimator element is spatially adjustable in at least one axis via one or more adjusting mechanisms to change the one or more levels of electromagnetic energy measured the detector.

Quality control phantom

A quality control phantom comprises a container and a frame to secure quality control accessories in position within the container during radiologic exposure testing.

Phantom system, use of the system, and imaging configuration having a phantom system
10172587 · 2019-01-08 · ·

A phantom system has a housing (2) with a lower part (3) having an opening in the z-direction and a cover part (4) for closing the opening of the housing (2). A first plate-shaped insert element (10a) has at least one depression (11a) for receiving a liquid substance. The lower part (3) and the cover part (4) delimit a cavity (5) with an insert area (8), which is constituted to receive the first insert element (10a). A first sealing element (14a) seals the first insert element (10a) against the cavity (5) and a fixing facility fixes the first insert element (10a) in the cavity (4) of the housing (2) in an operating state of the MPI phantom. The phantom permits good contrast in MPI, MRI, or CT using liquid contrast media.