Loading patent…
AssigneeGeneral Electric Company
InventorsBernhard Erich Hermann Claus, Jeffrey Wayne Eberhard
Estimating the term…
There is provided a method of constructing a three dimensional (3D) image of an object from a plurality of two dimensional (2D) views of the object, comprising the steps of filtering the plurality of 2D views of the object, and order statistics-based backprojecting the filtered 2D views into the 3D image of the object.
1] A method of constructing a three dimensional (3D) image of an object from a plurality of two dimensional (2D) views of the object, comprising the steps of:
2] The method of claim 1, further comprising a step of:
3] The method of claim 2, wherein the step of acquiring said plurality of 2D views comprises:
4] The method of claim 3, wherein the total angular range of the angle of projection is less than 360°.
5] The method of claim 4, wherein the total angular range of the angle of projection is less than about 90°.
6] The method of claim 1, wherein the object comprises breast tissue.
7] The method of claim 1, further comprising a step of:
8] The method of claim 1, further comprising a step of:
9] The method of claim 8, further comprising a step of:
10] The method of claim 9, wherein the step of compensating said segmented 2D views for the thickness of said object comprises the steps of:
11] The method of claim 1, wherein said object has a thickness T, and wherein the step of filtering said plurality of 2D views of the object comprises a step of:
12] The method of claim 11, wherein the step of filtering said plurality of 2D views of the object does not emphasize structures within said 2D views having a characteristic size less than a minimum character size by more than a maximum amount.
13] The method of claim 1, wherein the step of backprojecting said filtered 2D views into the 3D image of the object applies an order statistics based operator to said backprojected filtered 2D views on a voxel-by-voxel basis.
14] The method of claim 8, wherein the step of backprojecting said filtered 2D views into the 3D image of the object applies an order statistics based operator on a voxel-by-voxel basis only to voxels where each backprojected pixel corresponds to a ray passing through said object.
15] The method of claim 8, wherein the step of backprojecting said filtered 2D views into the 3D image of the object sets values at voxels in the 3D image where at least a single packprojected pixel corresponds to a ray not passing through the object to a predetermined value.
16] The method of claim 1, wherein the step of filtering said plurality of 2D views of the object comprises a step of:
17] The method of claim 1, further comprising a step of:
18] A program product for causing a tomosynthesis device to perform the steps of:
19] The program product of claim 18, wherein the step of acquiring said plurality of 2D views comprises the steps of:
20] The program product of claim 19, wherein the total angular range of the angle of projection is less than 360°.
21] The program product of claim 20, wherein the total angular range of the angle of projection is less than about 90°.
22] The program product of claim 18, further causing a tomosynthesis device to perform the step of:
23] The program product of claim 22, further causing a tomosynthesis device to perform the step of:
24] The program product of claim 23, wherein the step of compensating said segmented 2D views for the thickness of said object comprises the steps of:
25] The program product of claim 18, wherein the step of backprojecting said filtered 2D views into the 3D image of the object applies an order statistics based operator to said backprojected filtered 2D views on a voxel-by-voxel basis.
26] A method of compensating a 2D view for the thickness of an object to be analyzed, said view including pixels corresponding to rays passing through said object and pixels corresponding to rays not passing through said object, comprising the steps of:
27] The method of claim 26, wherein the object comprises breast tissue.
28] An imaging device for constructing a three dimensional (3D) image of an object from a plurality of two dimensional (2D) views of the object, comprising:
29] The imaging device of claim 28, wherein at least one of the plurality of 2D views does not include imaging of the object at a location about an edge portion of said detector, and wherein the step of backprojecting said filtered 2D views into the 3D image of the object at said location ignores views that do not include imaging at said location.
30] The imaging device of claim 28, wherein the total angular range of the angle of projection is less than 360°.
31] The imaging device of claim 28, wherein the processor is further programmed to perform a step of:
32] The imaging device of claim 28, wherein the processor is further programmed to perform a step of:
33] The imaging device of claim 32, wherein the processor is further programmed to perform a step of:
34] The imaging device of claim 33, wherein the step of compensating said segmented 2D views for the thickness of said object comprises the steps of:
35] The imaging device of claim 28, wherein the step of backprojecting said filtered 2D views into the 3D image of the object applies an order statistics based operator to said backprojected filtered 2D views on a voxel-by-voxel basis.
36] A method of reconstruction of three dimensional (3D) structures from a plurality of projection radiographs of tissue taken at different angles, the method comprising the steps of:
37] The method of claim 36, further comprising a step of:
38] A method of constructing a three dimensional (3D) image of an object from a plurality of two dimensional (2D) views of the object, comprising the steps of:
39] The method of claim 38, wherein the object comprises breast tissue.
40] The method of claim 38, further comprising at least one of:
From the US filing history. Foreign family members aren’t listed.
Backward citations are indexed for grants only.
Tomographic reconstruction from projections: image preprocessing, e.g. calibration, positioning of sources or scatter correction
Tomographic reconstruction from projections: inverse problem, i.e. transformations from projection space into object space
Computed tomography: limited angle
Image data processing or generation, in general
Term end not estimated
The present invention relates generally to digital imaging, and more particularly to reconstructing a three dimensional (3D) image using a tomosynthesis device.
It is well know in the medical community that breast cancer is a leading cause of death in women (and to a lesser extent also affects men). When early detection of abnormalities is combined with proper medical attention, however, the risk of death and/or severe medical ramifications can be drastically reduced. Many devices and techniques (e.g., mammography) are currently under development to detect breast abnormalities earlier, and with greater accuracy than conventional devices. A brief summary of some conventional devices, techniques, and their limitations follows.
Presently, the vast majority of mammography devices utilize conventional x-ray techniques. A patient's breast is positioned in an x-ray machine, which passes x-rays through the breast and generates a corresponding x-ray image on a film. The film is then analyzed by a trained clinician, who examines the film for abnormalities, such as a mass, a cyst, a microcalcification, a fibrous finding, an architectural distortion, and/or other abnormal findings related with benign or malignant abnormalities. In standard digital mammography, the x-ray image (or projection radiograph) is acquired by means of a digital detector, and the resulting digital image can be processed to enhance the visibility of structures within the image, thus providing a potentially more useful image to the clinician. These standard mammography techniques, however, suffer from many problems.
FIG. 1 is a diagram of a tomosynthesis device according to an embodiment of the present invention.
FIG. 2 is a flow chart of a method of constructing a 3D image of an object from a plurality of 2D views of the object according to an embodiment of the present invention.
FIG. 3 is a flow chart of a method of acquiring a plurality of 2D views of the object according to an embodiment of the present invention.
Reference will now be made in detail to presently preferred embodiments of the present invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
The present invention will be described in reference to apparatuses and methodology for breast imaging and breast cancer detection. It should be appreciated, however, that the teachings of the present invention may also be used in other areas, such as chest and lung imaging, orthopedic imaging, and other medical and non-medical applications (e.g., nondestructive evaluation).
A tomosynthesis device according to one embodiment of the present invention is shown in FIG. 1. A radiation source 110 for emitting x-ray radiation is angularly displaceable through a plurality of emission positions A, B, C corresponding to a plurality of views of the tissue 120. While only three emission positions are shown in FIG. 1, one of ordinary skill in the art will recognize that three emission positions or fewer or more emission positions may be utilized, while remaining within the scope of the invention. The radiation source 110 is angularly displaceable so as to enable acquisition of radiographs of the breast from different projection angles. This can be achieved, for example, by angularly displacing the radiation source 100 about a pivot point 150, preferably about 15 cm above the breast tissue. The radiation source 110 is angularly displaceable through a projection angle ((, which is preferably less than ±180°. Preferably, ((is in the range of less than about ±45°, and most preferably less than about ±30°. More preferably, at least 11 emission positions are used, and spaced at about constant angular spacings. In the system configuration of FIG. 1, the projection angle (( is generally significantly smaller than the “gantry angle” ((. The projection angle ((is essentially given by the angle of a ray of the beam passing through the “center” of the object, with reference to some “zero-degree” angle. Unlike in computed tomography (CT) scanning, the radiation source 110 is preferably not angularly displaceable all the way around the breast tissue 120.