Siemens Aktiengesellschaft

Siemens Corporate Research, Inc.

Other

Matthias Mitschke

Dieter Ritter

Nassir Navab

Norbert Rahn

Ali Reza Bani-Hashemi

Oliver Schuetz

Axel Hebecker

Rainer Graumann

Michael Scheuering

Karl Barth

Thomas Brunner

Karl Wiesent

Joachim Hey

Sorin-Alexandru Neagu

Lutz-Peter Nolte

Anders Steiner

Heinz Waelti

The present invention utilizes external motion sensors to determine a periodic motion of a patient being examined when generating a series of projected images with a C-arm X-ray device. Three-dimensional images are assembled based on the position information provided by the external motion sensors, and a corresponding four-dimensional image is constructed therefrom.

4D imaging with a C-arm X-ray system

In a method and apparatus for image support of an operative procedure implemented with a medical instrument, a two-dimensional x-ray image of a volume region to be treated is generated and stored with a C-arm x-ray apparatus in at least one pivot position of the C-arm. With a position detection device, the position of an apparatus reference system and the position of a reference system in the image generation are at least indirectly detected. Between the reference system and an image coordinate system of the x-ray image, a transformation rule is determined using known, apparatus-specific mapping rules that are measured and stored in a preceding calibration. During the subsequent procedure, with the position detection device the position of an instrument reference system is detected in the reference system and the instrument is mixed into the stored two-dimensional x-ray image with accurate position by means of this transformation rule.

Method and apparatus for image support of an operative procedure implemented with a medical instrument

In an image post-processing method and apparatus for 3D visualization of 2D/3D fused image data for use in catheter angiography in an endovascular interventional procedure, upon forward movement of a micro-catheter through blood vessel in the interventional procedure, x-ray images are acquired from different projection directions and are subjected to a pattern recognition algorithm for edge-based segmentation of the image regions filled by the micro-catheter, with all remaining image regions being masked out. The segmented projection exposures are prepared by a 3D reconstruction algorithm to obtain an image data set for (pseudo-) three-dimensional representation of the micro-catheter. This image data set are intraoperatively registered and fused with an image data set acquired from an angiographic pre-examination for three-dimensional visualization of the vessel topography. The reconstructed 3D representation of the catheter is mixed into the three-dimensionally prepared representation of endovascular blood vessel sections to be treated.

Method and apparatus for visualization of 2D/3D fused image data for catheter angiography

In a method for the intraoperative generating of an updated volume dataset, a first volume dataset is reconstructed from a series of n 2D X-ray projections (of a patient that are acquired at different angles. During a medical intervention, m 2D X-ray projections (m&#x3c;n) of the patient are acquired from different angles. In a first version of the method, m 2D X-ray projections of the series of n 2D X-ray projections are replaced by the intraoperatively acquired m 2D X-ray projections, and an updated volume dataset is reconstructed using the intraoperatively acquired m 2D X-ray projections and n&#x2212;m 2D X-ray projections that were not replaced in the series of n 2D X-ray projections. In a second version of the method, a second volume dataset is reconstructed with the intraoperatively acquired m 2D X-ray projections and is fused with the first volume dataset to form an updated volume dataset.

Method for intraoperative generation of an updated volume dataset

An apparatus for determining a coordinate transformation for mixing an image of a first subject into an X-ray image of a second subject has an arrangement for fastening the apparatus to the second subject, markers that can be acquired by a navigation system, and X-ray-positive marks. The positions and orientations of the markers that can be acquired with the navigation system and the positions and orientations of the X-ray-positive marks relative to one another are thus known, so a coordinate transformation can be determined between a coordinate system allocated to the navigation system and a coordinate system allocated to the X-ray image. Thus an image of the first subject that can be acquired with the navigation system can be mixed into an X-ray image of the second subject.

Apparatus for determining a coordinate transformation

In a method and apparatus for automatic marker-free fusion (matching) of 2D fluoroscopic C-arm images with preoperative 3D images using an intraoperatively acquired 3D data record, an intraoperative 3D image is obtained using a C-arm x-ray system, image-based matching of an existing preoperative 3D image in relation to the intraoperative 3D image is undertaken, which generates a matching matrix of a tool plate attached to the C-arm system is matched in relation to a navigation system, a 2D fluoroscopic image to be matched is obtained, with the C-arm of the C-arm system in any arbitrary location, a projection matrix for matching the 2D fluoroscopic image in relation to the 3D image is obtained, and the 2D fluoroscopic image is fused (matched) with the preoperative 3D image on the basis of the matching matrix and the projection matrix.

Method for marker-free automatic fusion of 2-D fluoroscopic C-arm images with preoperative 3D images using an intraoperatively obtained 3D data record

A registration method and an apparatus for navigation-guided interventions employing an X-ray device and a position acquisition system and avoid the use of patient-associated markers. By means of a defined arrangement of a carrying arm proceeding from a support mount at the X-ray device and a defined arrangement of an X-ray calibration phantom at the carrying arm, the coordinate transformation between a coordinate system allocated to the support mount and a coordinate system allocated to the X-ray calibration phantom is known. On the basis of the acquisition and evaluation of 2D projections of the X-ray calibration phantom with the X-ray device, a coordinate transformation between the coordinate system allocated to the support mount and a coordinate system allocated to a measurement volume of the X-ray device is produced. By arranging a device detectable by the position acquisition system at the support mount, a coordinate transformation between the coordinate system allocated to the measurement volume and a coordinate system allocated to the calibration phantom is determined for the navigation.

Registration method and apparatus for navigation-guided medical interventions, without the use of patient-associated markers

To intraoperatively generate an updated volume data set in which a image information of biological tissue is volume data set representing reconstructed from a series of n 2D biological tissue x-ray projections, one version, in intraoperatively acquired m 2D biological tissue x-ray projections the biological tissue 2D contour is segmented and this is back-projected in the reconstructed volume data set. In another version, in the volume data set the biological tissue 3D contour is segmented and this is projected in intraoperatively acquired m biological tissue 2D x-ray projections. The 3D contour is visually repositioned by projection in the m 2D x-ray projections in the volume data set, until its projection is substantially congruent with the biological tissue image information in the respective 2D x-ray projections. In both versions, a volume data set updated around the intraoperatively determined biological tissue 3D contour is generated.

Method for intraoperative generation of an updated volume data set

In a registration method for navigation-guided medical interventions using a position acquisition system, an X-ray device and an X-ray calibration phantom having X-ray-positive marks, the coordinates of marks of the X-ray calibration phantom that are present in the measurement volume of the X-ray device and imaged in the reconstructed volume are determined in a coordinate system allocated to the measurement volume of the X-ray device) and in a coordinate system allocated to the position acquisition system. The coordinate transformation between the coordinate system allocated to the measurement volume and the coordinate system allocated to the position acquisition system is determined on the basis of the coordinates of the X-ray-positive marks in the coordinate system allocated to the measurement volume and on the basis of the coordinates of the X-ray-positive marks in the coordinate system allocated to the position acquisition system.

Registration method for navigation-guided medical interventions

In a method and an apparatus for generating a volume dataset of a subject taking a movement of the subject into consideration, a referencing base is arranged at the subject, so that the positions and the orientations of the referencing base can be acquired during a registration of a series of 2D projections of the subject. The volume dataset of the subject is generated on the basis of the series of 2D projections as well as based on the deviations of the positions and of the orientations of the referencing base from a fixed reference position of the referencing base that are determined for all 2D projections of the series.

Method and apparatus for generating a volume dataset representing a subject

In a method for reconstructing 3D image data, a number of 2D central projections from different projection directions is acquired with a planar detector and radiation emanating from a radiation source, and a volume of interest of an examination subject to be three-dimensionally reconstructed is identified by mixing in variable and mutually dependent marks into at least two 2D central projections.

Method for reconstructing 3D image data with respect to a volume of interest of an examination subject

A calibration phantom includes an arrangement of markings with a first X-ray absorption capability and a second X-ray absorption capability, with the arrangement of markings precluding superimposition of an image of a first marking with an image of a second marking for a sufficient number of successive markings for each projection condition, the physical embodiment of a marking representing a value assignment, and the value assignment of a respective specific first number of adjacent markings in each case forming first code information, with each of the first code information items being unique within the first code information which is formed in the totality of markings and in both reading directions.

Calibration phantom for projection X-ray systems

An X-ray calibration dummy (RP) having markings ( ) that may be acquired by a position-acquisition system ( ). The invention also concerns a method for nonmarker-based registration for use in navigation-guided operations employing the X-ray calibration dummy (RP). A medical system for carrying out the method has a C-shaped X-ray machine ( ), a position-acquisition system, and the X-ray calibration dummy (RP).

X-RAY CALIBRATION DUMMY, A METHOD FOR NON-MARKER-BASED REGISTRATION FOR USE IN NAVIGATION-GUIDED OPERATIONS EMPLOYING SAID X-RAY CALIBRATION DUMMY, AND A MEDICAL SYSTEM HAVING SUCH AN X-RAY CALIBRATION DUMMY

In a method for determining a coordinate transformation between a coordinate system of a first object to be imaged by an X-ray apparatus and a coordinate system of a second object to be navigated relative to a first object, a transformation relationship is determined between a coordinate system of a position-acquisition system and the coordinate system of the first object by an offline calibration run, the position of the X-ray arm is determined while recording X-ray images of the first object, and the position of the second object is determined using the position-acquisition system.

Method for determining a coordinate transformation for use in navigating an object

Superimposed X-ray and video images can be obtained by acquiring the respective images from the optically equivalent points in space. One or more mirrors may be used to acquire the images and direct them towards the camera. The images can then be combined by warping one onto the other.

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Nuremberg, Germany

Matthias Mitschke