Three-Dimensional Reconstruction of an Object from Projection Photographs
First Claim
1. A device for the three-dimensional reconstruction of a moving object in a body volume, comprising a memory which contains a series of two-dimensional projection photographs (A1 A2, An, AN) of the body volume from different directions, as well as a data processing unit which is coupled to the memory and which is set up to execute the following steps:
- a) Segmentation of the image (Prn(Q)) of at least one feature point (Q) of the object or its surroundings in the projection photographs (An);
b) Specifications of a spatial reference position (Q0) for each feature point (Q);
c) Calculation of transformations (Σ
n, σ
n) of the object space and of the projection photographs (An), after the use of which the projection of the transformed reference position coincides with the respective of the transformed reference position coincides with the respective transformed image of the feature point;
d) Three-dimensional reconstruction of the object from the projection photographs (An) with the aid of the calculated transformations (Σ
n, σ
n).
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Accused Products
Abstract
The invention relates to a method for the three-dimensional reconstruction of an object such as for example a stent (5) in the coronary vessels of a patient. In the course of this, a series of X-ray projection photographs (A,) are produced from different directions, with the relevant ECG phase (E,) being recorded simultaneously. On the projection photographs (A,), the position of feature points (R, Q) is segmented (a). The photographs (A,) are furthermore allocated (b) into classes (Kp) according to their belonging to different sections (Epcl) of the heartbeat phase. For each of these classes, the corresponding spatial position ((x,y,z)Qp) of the feature points is established (e). In the next step (d), from the positions of the feature points (R, Q) that are now known for various heartbeat phases, the displacement vectors (SRp-m, SQp-m) or generally the transformations (Epm) are calculated which link (d) the positions of the feature points for different heartbeat phases (p, m). With the aid of these transformations, in a last step (e) a three-dimensional reconstruction can then be carried out for the whole stent (5) or its surroundings, by referring back to all the X-ray projection photographs from different heartbeat phases (p1, p2). In an alternative embodiment of the invention, projection photographs of a moving body volume are transformed such that the images of feature points that are located on the photographs respectively come to rest at a place on which (randomly) set spatial reference positions for the feature points are projected. With the projection photographs that are thus aligned onto the reference positions, three-dimensional reconstruction of the object can subsequently take place.
8 Citations
10 Claims
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1. A device for the three-dimensional reconstruction of a moving object in a body volume, comprising a memory which contains a series of two-dimensional projection photographs (A1 A2, An, AN) of the body volume from different directions, as well as a data processing unit which is coupled to the memory and which is set up to execute the following steps:
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a) Segmentation of the image (Prn(Q)) of at least one feature point (Q) of the object or its surroundings in the projection photographs (An);
b) Specifications of a spatial reference position (Q0) for each feature point (Q);
c) Calculation of transformations (Σ
n, σ
n) of the object space and of the projection photographs (An), after the use of which the projection of the transformed reference position coincides with the respective of the transformed reference position coincides with the respective transformed image of the feature point;
d) Three-dimensional reconstruction of the object from the projection photographs (An) with the aid of the calculated transformations (Σ
n, σ
n). - View Dependent Claims (2, 3, 5, 6, 7, 8)
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4. Device for the three-dimensional reconstruction of an object (5) in a body volume that is subject to cyclical self-movement, comprising a memory (3) which contains a series of two-dimensional projection photographs (An) of the body volume from different directions together with the respective corresponding values of a parameter (En) that characterizes the cylindrical self-movement, as well as a data processing unit (4) which is coupled to the memory (3) and which is set up to execute the following steps:
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a) Segmentation of the image (Rn, Qn) of at least one feature point (R, Q) of the object (5) in the projection photographs (An);
b) Classification of the projection photographs (An) into classes (Kp) which each correspond to a given phase (EpC1) of the cyclical self-movement;
c) Three-dimensional localization of said feature point (R, Q) for each of the said classes (Kp) from at least two projection photographs (An1, An2) of this class;
d) Calculation of three-dimensional transformations (Σ
p— m) which describe the movement (SRp— m, SQp— m) of the localized feature point (R, Q) between different phases (p, m) of the cyclical self-movement;
e) Three-dimensional reconstruction of the object (5) from the projection photographs (An) with the aid of the calculated transformations (Σ
p— m).
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9. Method for the three-dimensional reconstruction of a moving object in a body volume based on a quantity of data which contains a series of two-dimensional projection photographs (A1, A2, An, AN) of the body volume from different directions, comprising the steps:
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a) Segmentation of the image (Prn(Q)) of at least one feature point (Q) of the object or its surroundings in the projection photographs (An);
b) Specification of a spatial reference position (Q0) for each feature point (Q);
c) Calculation of transformations (Σ
n, σ
n) of the object space and of the projection photographs (An), after the use of which the projection of the transformed reference position coincides with the transformed image of the feature point each time;
d) Three-dimensional reconstruction of the object from the projection photographs (An) with the aid of the calculated transformations (Σ
n, σ
n).
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10. Method for the three-dimensional reconstruction of an object (5) in a body volume that is subject to a cyclical self-movement, based on a quantity of data which contains a series of two-dimensional projection photographs (An) of the body volume from different directions together with the respective corresponding values of a parameter (En) that characterizes the cyclical self-movement, comprising the steps:
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a) Segmentation of the image (Rn, Qn) of at least one feature point (R, Q) of the object (5) in the projection photographs (An);
b) Classification of the projection photographs (An) into classes (Kp) which each correspond to a given phase (EpC1) of the cyclical self-movement;
c) Three-dimensional localization of said feature point (R, Q) for each of the said classes (Kp) from at least two projection photographs (An1, An2) of this class;
d) Calculation of three-dimensional transformations (Σ
p— m) which describe the movement (SRp— m, SQp— m) of the localized feature point (R, Q) between different phases (p, m) of the cyclical self-movement;
e) Three-dimensional reconstruction of the object (5) from the projection photographs (An) with the aid of the calculated transformations transformations (Σ
p— m).
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Specification
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- Resources
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Current AssigneeKoninklijke Philips N.V.
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Original AssigneeKoninklijke Philips N.V.
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InventorsMovassaghi, Babak, Rasche, Volker
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Granted Patent
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Time in Patent OfficeDays
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Field of Search
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US Class Current382/131
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CPC Class CodesG06T 11/005 Specific pre-processing for...G06T 2211/412 DynamicG06T 7/70 Determining position or ori...
