Tomography System and Method for Large-volume Recordings

Abstract

A tomography system includes a first radiation source and a first detector that is assigned to the first radiation source. The tomography system also includes a second radiation source and a second detector that is assigned to the second radiation source. The tomography system is prepared to perform a scan. In a first plane of rotation, the first detector is guided along a first circular segment-shaped path. In a second plane of rotation, the second detector is guided in synchrony along a second circular segment-shaped path. The tomography system is configured to obtain a first data record with the first detector and a second data record with the second detector. The first plane of rotation and the second plane of rotation are arranged at a distance from one another.

Claims

1. A tomography system comprising: a first radiation source and a first detector that is assigned to the first radiation source; a second radiation source and a second detector that is assigned to the second radiation source, wherein the tomography system is configured to perform a scan, wherein in a first plane of rotation, the first detector is guided along a first circular segment-shaped path, while in a second plane of rotation, the second detector is guided in synchrony along a second circular segment-shaped path, wherein the tomography system is configured to obtain a first data record with the first detector and a second data record with the second detector, and wherein the first plane of rotation and the second plane of rotation are arranged at a distance from one another.

2. The tomography system of claim 1, wherein the tomography system is configured to generate a comprehensive two-, three- or four-dimensional data record from the first data record and the second data record prior to an image reconstruction.

3. The tomography system of claim 1, wherein the tomography system is configured to generate a first two-, three- or four-dimensional image from the first data record using a first image reconstruction, a second two-, three- or four-dimensional image from the second data record using a second image reconstruction, and a comprehensive two-, three-, or four-dimensional image from the first image and the second image.

4. The tomography system of claim 1, wherein the first plane of rotation and the second plane of rotation minus an overlapping width are distanced by less than half the width of the first detector plus half the width of the second detector.

5. The tomography system of claim 1, wherein the second circular segment-shaped path is arranged concentric to the first circular segment-shaped path, a radius of the first circular segment-shaped path is the same size as a radius of the second circular segment-shaped path, or a combination thereof.

6. The tomography system of claim 1, wherein a starting position of the second circular segment-shaped path is offset in a direction of rotation by a circumferential angle difference with respect to the starting position of the first circular segment-shaped path.

7. The tomography system of claim 1, wherein the tomography system is configured to perform a short scan with the first detector, the second detector, or the first detector and the second detector.

8. The tomography system of claim 1, wherein the tomography system is configured to perform a large volume scan with the first detector, the second detector, or the first detector and the second detector.

9. The tomography system of claim 1, wherein the first data record is two-, three- or four-dimensional, the second data record is two-, three- or four-dimensional, or a combination thereof.

10. A method for operating a tomography system, the method comprising: performing a scan, the performing of the scan comprising guiding a first detector in a first plane of rotation along a first circular segment-shaped path, and guiding a second detector in a second plane of rotation in synchrony along a second circular segment-shaped path, wherein the first plane of rotation and the second plane of rotation are arranged at a distance from one another; and obtaining a first data record with the first detector and obtaining a second data record with the second detector.

11. The method of claim 10, further comprising generating, by the tomography system, a comprehensive two-, three- or four-dimensional data record from the first data record and the second data record prior to an image reconstruction.

12. The method of claim 10, further comprising generating, by the tomography system, a first two-, three- or four-dimensional image from the first data record using a first image reconstruction, a second two-, three- or four-dimensional image from the second data record using a second image reconstruction, and a comprehensive two-, three-, or four-dimensional image from the first image and the second image.

13. The method of claim 10, wherein the first plane of rotation and the second plane of rotation minus an overlapping width are distanced by less than half the width of the first detector plus half the width of the second detector.

14. The method of claim 10, wherein the second circular segment-shaped path is arranged concentric to the first circular segment-shaped path, a radius of the first circular segment-shaped path is the same size as a radius of the second circular segment-shaped path, or a combination thereof.

15. The method of claim 10, wherein a starting position of the second circular segment-shaped path is offset in a direction of rotation by a circumferential angle difference with respect to the starting position of the first circular segment-shaped path.

16. The method of claim 10, further comprising performing, by the tomography system, a short scan with the first detector, the second detector, or the first detector and the second detector.

17. The method of claim 10, further comprising performing, by the tomography system, a large volume scan with the first detector, the second detector, or the first detector and the second detector.

18. The method of claim 10, wherein the first data record is two-, three- or four-dimensional, the second data record is two-, three- or four-dimensional, or a combination thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 shows a not to scale schematic perspective representation of one embodiment of a biplanar tomography system having a patient couch and two C-arms;

[0022] FIG. 2 shows a not to scale schematic perspective representation, of the patient couch and an exemplary geometry of a recording of a comprehensive data record or reconstruction of a comprehensive volume image that may be performed with the biplanar tomography system; and

[0023] FIG. 3 shows a schematic representation of an exemplary course of a method for operating a tomography system.

DETAILED DESCRIPTION

[0024] A biplanar tomography system R shown in FIG. 1 has a first C-arm C1, a second C-arm C2, and a patient couch PA. A first radiation source Q1 and a first detector RD1 are fastened to the first C-arm C1. A second radiation source Q2 and a second detector RD2 are fastened to the second C-arm C2. In order to perform a comprehensive scan on an object ZO to be examined, the first C-arm C1 performs an angular rotation RA about an orbital axis OA, while the second C-arm C2 carries out an orbital rotation RO about the same orbital axis OA. With the orbital rotation RO of the second C-arm C2, the plane (e.g., intended plane), in which the second C-arm C2 is disposed, remains unchanged. With the angular rotation RA of the first C-arm C1, the first C-arm C1 rotates about a fastening axis BA1 of the C-arm. A comprehensive scan, in which the first C-arm C1 and the second C-arm C2 are arranged in front of the scan, may also be performed such that both the first C-arm C1 and the second C-arm C2 carry out an angular rotation during the scan or that the first C-arm C1 and the second C-arm C2 are arranged in front of the scan such that both C-arms C1, C2 carry out an orbital rotation during the scan.

[0025] The geometry of a recording of a comprehensive data record or reconstruction of a comprehensive volume image that may be performed with the biplanar tomography system and is shown in FIG. 2 shows a first circular segment-shaped path BK1D with a starting position AP1 and an end position EP1 of a center point MP1 of the first detector RD1. FIG. 2 shows a second circular segment-shaped path BK2D with a starting position AP2 and an end position EP2 of a center point MP2 of the second detector RD2. FIG. 2 also shows a schematic representation of a spatial position of a recording region AB1 of a first data record DS1, which is detected with the first detector RD1 during the scan, and a spatial position of a recording region AB2 of a second data record DS2, which is detected with the second detector RD2 during the scan. Depending on the application, either a scan in portrait mode or a scan in landscape mode may be provided for the body organ or vascular structure to be examined. In portrait mode, the longer principal longitudinal axis of the detector runs in parallel to the orbital axis, while in landscape mode the longer principal longitudinal axis of the detector runs horizontally to the orbital axis.

[0026] The two recording regions AB1, AB2 spatially overlap one another in a shared overlapping region UB. If the two data records DS1, DS2 are three or four-dimensional, the shared overlapping region is an overlapping volume UV, which is likewise shown schematically in FIG. 2. Typically, the overlapping is only partial in the direction of the orbital axis, but in all other dimensions, the overlapping is complete. This applies irrespective of whether the data records are two-, three- or four-dimensional. If as complete an overlapping as possible is desired in the remaining dimensions, this may, inter alia, be achieved in that the detectors RD1, RD2 for the synchronous scan are either aligned both in a portrait mode or both in a landscape mode. Applications, in which a comprehensive scan with different modes is provided, exist (e.g., a scan in the landscape mode is combined with a scan in the portrait mode (head in the landscape mode and upper vertebra in the portrait mode; pelvis in the landscape mode and lower vertebra in the portrait mode)).

[0027] In one embodiment, a comprehensive two-, three- or four-dimensional data record DS12 is generated from both data records DS1, DS2 before an image reconstruction. The data of the second data record DS2 may be compared with the data of the first data record DS1 in the adjoining region, in the overlapping region UB, or in the overlapping volume UV and may be matched to the data of the first data record DS1 using a spatial and/or temporal mapping, so that a comprehensive data record DS12 is created. The data of the comprehensive data record DS12 in the adjoining region, in the overlapping region UB, or in the overlapping volume UV represents an interference-free transition between the first DS1 and the second data record DS2. Suitable methods for such a manual or automatic adjustment between two data records DS1, DS2 are not described here, since such methods are known to the person skilled in the art under the term registration.

[0028] A further embodiment of the tomography system provides that the tomography system is configured to generate a first two-, three- or four-dimensional image from the first data record DS1 using a first image reconstruction, a second two-, three- or four-dimensional image from the second data record DS2 using a second image reconstruction, and a comprehensive two-, three- or four-dimensional image from the first and second image. The data of the second reconstructed image may be compared with the data of the first reconstructed image in the adjoining region, in the overlapping region UB, or in the overlapping volume UV and may be matched to the data of the first image using a spatial and/or temporal mapping, so that a comprehensive image is created. The data of the comprehensive image at a joint between the first and the second image or in the overlapping region UB or overlapping volume UV represents an interference-free transition between the first and the second image. Suitable methods for a manual or automatic adjustment between two images, which are known to the person skilled in the art under the term registration, may also be used.

[0029] In one embodiment, the two planes of rotation RE1, RE2 minus an overlapping width BU are distanced by less than half the width HB.sub.RD1 of the first detector RD1 plus half the width HB.sub.RD2 of the second detector RD2. The overlapping width BU amounts, for example, to between 10% and 20% of half the width HB.sub.RD1 of the first detector RD1 in the orbital axis direction OAR or half the width HB.sub.RD2 of the second detector RD2 in the orbital axis direction OAR. Using a spatial overlapping of the recording regions AB1, AB2, which may be detected by the detectors RD1, RD2, a spatial gap may also be avoided in the comprehensive overall recording by taking tolerances into account. A structure of the object ZO to be examined may be used to compare the data of the second data record DS2 with the data of the first data record DS1 in the overlapping volume UB or in the overlapping volume UV and using a spatial and/or temporal mapping to match the spatial and/or temporal mapping to the data of the first data record DS1 such that a comprehensive data record DS12 is created. The data of the comprehensive data record DS12 in the overlapping volume UB or overlapping region UV represents an interference-free transition between the first AB1 and the second AB2 recording region.

[0030] The method 100 shown in FIG. 3 for operating a tomography system R includes, in a first treatment 110, performing a scan. In a first plane of rotation RE1, a first detector RD1 is guided along a first circular segment-shaped path BK1D, while in a second plane of rotation RE2 a second detector RD2 is guided in synchrony along a second circular segment-shaped path BKD2. In a second treatment 120, a first data record DS1 is obtained with the first detector RD1, and a second data record DS2 is obtained with the second detector RD2. The two planes of rotation RE1, RE2 are arranged at a distance from one another.

[0031] One or more of the present embodiments relate to a tomography system R having a first radiation source Q1 and a first detector RD1 that is assigned to the first radiation source Q1. The tomography system R also includes a second radiation source Q2 and a second detector RD2 that is assigned to the second radiation source Q2. The tomography system R is prepared to perform a scan. In a first plane of rotation RE1, the first detector RD1 is guided along a first circular segment-shaped path BKD1, while in a second plane of rotation RE2, the second detector RD2 is guided in synchrony along a second circular segment-shaped path BKD2. The tomography system R is prepared to obtain a first data record DS1 with the first detector RD1 and a second data record DS2 with the second detector RD2. The two planes of rotation RE1, RE2 are arranged at a distance from one another.

[0032] The elements and features recited in the appended claims may be combined in different ways to produce new claims that likewise fall within the scope of the present invention. Thus, whereas the dependent claims appended below depend from only a single independent or dependent claim, it is to be understood that these dependent claims may, alternatively, be made to depend in the alternative from any preceding or following claim, whether independent or dependent. Such new combinations are to be understood as forming a part of the present specification.

[0033] 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.