Patent Application
20130070907
This application claims the benefit of DE 10 2011 005 847.8, filed on Mar. 21, 2011.
The present embodiments relate to an x-ray device.
Angiography applications have an important place in intraoperative imaging. Modern 3D image reconstruction procedures are gaining in significance alongside the conventional tasks of angiography modalities (e.g., vessel imaging using statically but flexibly positionable recording systems). To generate the required data, image sequences are recorded over precisely defined paths of the image recording system. These techniques may already be deployed within limits using existing modalities (e.g., DynaCT, SpiralCT).
C-arm x-ray devices represent a widely used model of the x-ray devices used in angiography. A C-arm supporting an x-ray source and an associated detector may be pivotably attached in a movable fashion to a displaceable unit (e.g., see
While C-arm x-ray devices are designed primarily for the flexible but static acquisition of projection recordings, computed tomography devices operating with x-ray radiation sources traveling along an orbital ring about an axis of rotation are used to generate sectional image recordings. In certain areas, computed tomography devices may be replaced by C-arm x-ray devices with an extended functional scope. These C-arm x-ray devices may also generate sectional images. Sectional images are generated from image sequences obtained using a recording system that may be displaced along a trajectory. The reconstruction quality is not as good as may be achieved using a computed tomography device. Also, the image recording system may not be rotated completely.
This is because very high rotation speeds of the image recording system are attained with the CT device. Reconstruction artifacts that result due to the movement of the patient or organs (e.g., heart) during a recording are thus reduced to a minimum. The fact that the system may be constructed in a very rigid fashion provides that the rotation is highly reproducible. This allows the initially measured circuit of beam focus and detector to be repeated very accurately, so that a very precise reconstruction is achieved by the stored projection matrices.
DynaCT and similar 3D reconstructions that may be performed using C-arms may be implemented with limited quality. To achieve a higher quality, 1) the rotation speed may be increased, and 2) the systems may be improved with respect to reproducibility.
This proposal cannot be achieved, however, with the currently available C-arm system structures.
Even if some angiography systems are already able to allow the C-arm to rotate at higher speeds, the open structure represents a considerable safety risk for patient and staff when the C-arm rotates faster than 90°/s (compared with CT: >1000°/s).
The C-arm structure of the prior art may be oscillation-prone. These unwanted oscillations are not fully reproducible. Since there is no actuator system present in the structure to allow active compensation for oscillations, extremely accurate reproducibility is difficult or impossible to achieve. Also, the system moving the C-arm only has limited repetition accuracy for each axis. With serial kinematics, these reproducibility errors accumulate in the worst case.
The present embodiments may obviate one or more of the drawbacks or limitations in the related art. For example, the abovementioned disadvantages may be overcome.
In one embodiment, an x-ray device has an x-ray emitter and an associated recording system (e.g., a flat-screen detector). The x-ray emitter and the recording system (e.g., x-ray components) are each supported directly or indirectly by at least one arm.
An appropriate shoulder joint construction may be used to position kinematic arms in a ring structure and anchor the kinematic arms in the ring structure with a defined form fit. If the ring itself is supported by a slip ring and driven in a rotary fashion according to the same approach as in DE 10 2008 032 294 A1 and the corresponding U.S. Pat. No. 7,988,357, which is hereby incorporated by reference, high rotation speeds may be attained if the system has a very high level of rigidity. Such speeds are not safety-critical, since the system is closed by the ring in the direction of the patient and staff. If free patient access is to provided, as in interventional imaging, for example, the arms move out of the ring structure and form the usual pattern of the system proposed in DE 10 2008 032 294 A1 with all the degrees of freedom of movement. One advantageous secondary effect of the proposed structure is the extreme compactness of the system in the retracted position.
One advantage is the possible attainment of high rotation speeds (like CT) with reproducibility of the circular movement with a system also suitable for interventional imaging due to its open structure. High 3D imaging quality combines with the advantages of the open C-arm structure.
For an x-ray system (e.g., an x-ray device) having a a joint configuration (RRSRRR), the radius of a drum 1 is enlarged (
While the present invention has been described above by reference to various embodiments, it should be understood that many changes and modifications can be made to the described embodiments. It is therefore intended that the foregoing description be regarded as illustrative rather than limiting, and that it be understood that all equivalents and/or combinations of embodiments are intended to be included in this description.
| Number | Date | Country | Kind |
|---|---|---|---|
| DE 102011005847.8 | Mar 2011 | DE | national |
