Koninklijke Philips Corporation N.v.

Ion Beam Applications S.a.

Peter George Van De Haar

Jan Timmer

Fred Simon Berend Van Nijnatten

Erik Hummel

Petrus Johannes Withagen

Joost Adrianus Van Rooijen

Michael Grass

Bernardus Hendrikus Wilhelmus Hendriks

Robert Johannes Frederik Homan

Walter Ruetten

Heidrun Steinhauser

Christian Reich

Herman Stegehuis

Dirk Schäfer

Ronaldus Frederik Johannes Holthuizen

Johan Juliana Dries

Onno Jan Wimmers

Jarich Willem Spliethoff

William Edward Peter Van Der Sterren

Edward Vuurberg

Johanneke Gerrigje Groen

Sebastien Brousmiche

Bernard Johannes Brendel

Jan Rongen

Keshav Simhadri

Dirk SCHÄFER

Bernhard Johannes Brendel

The present invention relates to guidance during a medical intervention. In order to provide an improved navigation support with a facilitated setup, a system () for navigation support is provided. An image data input () receives a plurality of acquired 2D X-ray images of a subject's body from different angles. A set of markers, which are visible in X-ray images and which are detectable by a navigation system, is assigned to the subject. A marker detecting arrangement () is provided that detects a current spatial location of the markers assigned to the subject. A data processor () reconstructs a 3D volume of the subject based on the plurality of 2D X-ray images. At least a part of the markers is arranged outside the volume covered by the reconstructed 3D volume of the subject, while the markers are visible in the 2D X-ray images. The data processor () identifies the markers in the 2D X-ray images based on image data of the plurality of 2D X-ray images outside the 3D volume and determines a spatial location of the markers in relation to the 3D volume of the subject. The data processor () also registers the reconstructed 3D volume of the subject to a current spatial position of the subject based on the detected current spatial location of the markers and the determined spatial location of the markers in relation to the 3D volume of the subject. An output interface () provides the registered reconstructed 3D volume for navigation.

Navigation support

An X-ray system comprises an assembly that is moveable to different scan coordinates to acquire X-ray projection images at the different scan coordinates in a dynamic mode while the assembly is moving. The assembly is also moveable to a predetermined reference coordinate to acquire an X-ray projection image at the predetermined reference coordinate in a static mode while the assembly is resting. The X-ray system also comprises a processor configured to obtain dynamic gain calibration parameters from the X-ray projection images acquired in the dynamic mode at one of the different scan coordinates; obtain a static gain calibration parameter from the X-ray projection image acquired in the static mode at the predetermined reference coordinate; and determine adjusted dynamic gain calibration parameters.

Static gain calibration

An X-ray detector is positioned relative to an X-ray source such that at least a part of a region between the X-ray source and the X-ray detector is an examination region for accommodating an object. The X-ray source and X-ray detector are controlled by a processing unit in order to operate in a first imaging operation mode, a second imaging operation mode, and/or a third imaging operation mode. The detector comprises a first scintillator, a second scintillator, a first sensor array, and a second sensor array. The first scintillator is disposed over the second scintillator such that X-rays emitted from the X-ray source first encounter the first scintillator and then encounter the second scintillator.

Detector for X-ray imaging

The present invention relates to a device for controlling a position of an anti-scatter grid in an X-ray image acquisition system, the device () comprising: a measurement unit (); a control unit (); and a shifting unit (); wherein the measurement unit () is configured to determine an X-ray beam focus position () of an X-ray radiation source of the X-ray image acquisition system with respect to an X-ray detector of the X-ray image acquisition system; wherein the control unit () is configured to generate a shifting signal based on a displacement () between the X-ray beam focus position () and a grid focus position () of the anti-scatter grid; and wherein, based on the shifting signal, the shifting unit () is configured to shift an anti-scatter grid of the X-ray image acquisition system in at least one direction to align the anti-scatter grid with the X-ray beam focus position (), provides an improved anti-scatter grid for X-ray acquisition systems. The invention provides the use of an improved anti-scatter grid () for X-ray acquisition systems ().

Device, system and method for controlling a position of an anti-scatter grid in an X-ray image acquisition system

The invention relates to off-center detector 3D X-ray or proton radiography reconstruction. Redundancy weighting with a steep weighting function around the iso-axis typically leads to artifacts in the reconstruction, for example, if inconsistencies between two nominal redundant projections occur, e.g. due to slightly incorrect detector calibration or scatter correction, etc. With the present invention, an approach is presented for overcoming or mitigating these problems.

Scaled radiography reconstruction

An image processing system (IPS) and related method for image reconstruction operations, in particular for spectral computed tomography imaging. The image reconstruction operation is based on optimizing a regularized objective or cost function. The objective function includes a regularization term (R) that incorporates, as a-priori knowledge, a known amount of a material resident within a field of view to be reconstructed.

Method for the reconstruction of quantitative iodine maps using energy resolved tomography

A Computer Tomography (CT) C-arm system and method for examination of an object is provided. The Computer Tomography (CT) C-arm system for examination of an object of interest, the CT- C-arm system comprises an X-ray tube adapted for generating X-rays, an X-ray detection unit to acquire a set of CT slices, wherein the X-ray tube, and the X-ray detection unit are adapted to be rotatable on a C-arm around a common axis around the object under examination and a processing unit by which the following steps are executable: acquiring a first 3D data volume of the CT slices using first scan parameters; adjusting the first data volume to a second data volume (segmented volume) such that voxel values of the first data volume of at least one predefined range of Hounsfield (H) are set to an at least one predefined H-value; generating a forward projection of the second data volume using the first scan parameters; reconstructing the projection to a third data volume; generating a fourth data volume (artefact-only volume) by subtracting the third volume with the second volume; generating a fifth volume by adding the first volume with the fourth volume.

Computer Tomography (CT) C-arm system and method for examination of an object

It is described a gain calibration for a two-dimensional X-ray detector (), in which the gain coefficients for scattered radiation () and direct radiation () are measured or estimated separately. A weighed average may be applied on the appropriate scatter fraction. The scatter fraction depending gain calibration method produces less ring artifacts in X-ray images as compared to known gain calibration methods, which do not take into account the fraction of scattered radiation reaching the X-ray detector ().

X-ray detector gain calibration depending on the fraction of scattered radiation

An imaging system including an artifact reducer arranged to correct for a ring-shaped artifact in a three-dimensional reconstructed volume. The artifact reducer includes a first stage correction arranged to eliminate structured noise of an output screen of an image intensifier of an X-ray imaging apparatus using a first corrective image. A raw image of a patient is first processed with the first corrective image. The gain-corrected images are forwarded to an image deformation correction where a suitable unwarping function performed. The gain-corrected unwarped images are then made available to a second stage gain correction where a second corrective image is applied resulting in a final set of images with a substantially reduced ring-shaped artifact. The final set of images is made available to an image reconstructor arranged for further processing of the final set of images, the result thereof being visualized on a computer monitor for inspection purposes.

Imaging system, an x-ray imaging apparatus, a method and a computer program arranged for reducing an artifact in a three-dimensional reconstructed volume

A method for at least reducing the occurrence of differential ghosting in an X-ray image acquired in respect of a subject, wherein a deghost scan is performed at least once daily so as to generate an underlying strong homogeneous ghost so that further differential (non-homogeneous) ghosting during subsequent scans is minimised. The deghost scan comprises acquiring an 'air' image, when no subject is present between the X-ray source () and detector (), as a relatively high detector dose.

Method for reducing 3D ghost artefacts in an x-ray detector

A computed tomography apparatus ( ) for performing volumetric helical imaging acquires helical computed tomography imaging data ( ) using a tilted gantry geometry. In the tilted gantry geometry, a rotational plane of a rotating radiation source ( ) is tilted at an angle (&khgr;) with respect to a direction (Z) of linear motion of a subject. A transform processor ( ) transforms ( ) the imaging data ( ) to a zero tilt geometry. A rebinning processor ( ) rebins ( ) the transformed imaging data ( ) to a non-sheared detector window. A reconstruction processor ( ) reconstructs ( ) the transformed and rebinned imaging data ( ) to generate a three-dimensional image representation ( ). Optionally, an image transform processor ( ) transforms ( ) the reconstructed image representation ( ) with an inverse of the zero tilt geometry transformation ( ).

Reconstruction method for tilted-gantry computed tomography

Conditional access system for controlling the access of receivers of end-users to a data content source in an uplink system. Said uplink system comprises a scrambler for scrambling data content supplied from the data content source, an entitlement control message generator for generating entitlement control messages containing a control word and an entitlement identification and a transmitter for transmitting the scrambled data content and the entitlement control messages. A descrambler and an entitlement control message decoder are associated to the receiver. If a match between the entitlement in the entitlement control message and the entitlement of the end-user exists, the entitlement control message decoder supplies a control word to the descrambler for descrambling a part of the received scrambled content for which the receiver is entitled. A separator is coupled to the data content source for separating a part of the data content from said source into at least one object data stream representing a preselected object of the data content part and a remaining data stream representing the data content part without the object data. The at least one object data stream is supplied to the input of the scrambler. A combiner is connected to the output of the descrambler for combining the descrambled object data with the remaining data content. An individual entitlement is allocated to said object.

Growing community of inventors

Eindhoven, Netherlands

Peter George Van De Haar