Method for image registration processes and X-ray angiography system
Registration of preoperatively acquired MRI images of soft parts to intraoperatively acquired X-ray images of soft parts is not possible. The invention shows a way of nevertheless using such preoperatively acquired images for superimposition with 2D projections of the soft parts, taking an indirect route via 3D/3D registration of images of the spinal column. For this purpose, 3D image data sets of the spinal column must be obtained separately on the one hand using MRI and on the other using the X-ray imaging system so that the 3D/3D registration produces a mapping rule which then also applies to the preoperatively acquired images of the soft part if the soft part images and the spinal images are acquired without intervening change in the patient position in the MRI scanner.
1. A method for an image registration process, comprising:
creating a first 3D image data set of a patient by a first image acquisition system, wherein the first 3D image data set comprises imaging of a part of the body of the patient comprising soft tissue, wherein one or more imaging parameters of the first image acquisition system are selected for soft tissue imaging;
creating a second 3D image data set of the patient by the first image acquisition system, wherein the second 3D image data set comprises imaging of a part of the body of the patient comprising an skeletal structure, wherein one or more imaging parameters of the first image acquisition system are selected for skeletal imaging;
transmitting the first and the second 3D image data set of the patient to a second image acquisition system, which is not suitable for soft tissue imaging;
creating a third 3D image data set of the patient by the second image acquisition system, wherein the third 3D image data set comprises imaging of the part of the body of the patient comprising the skeletal structure imaged by the first image acquisition system;
determining a mapping rule for a coordinate transformation from the second 3D image data set to the third 3D image data set based on a registering of the skeletal structure having been respectively imaged by the first image acquisition system in the second 3D image data set and by the second image acquisition system in the third 3D image data set;
processing the determined mapping rule to relate the first 3D image data set which comprises imaging of the part of the body of the patient comprising soft tissue, to a coordinate system of the second image acquisition system, which is not suitable for soft tissue imaging; and
generating a representation of the part of the body of the patient comprising soft tissue from the first 3D image data set related to the coordinate system of the second image acquisition system, and effective for registering the representation of the part of the body of the patient comprising soft tissue with a 2D image recorded by second image acquisition system.
2. The method as claimed in claim 1 , wherein the representation of the patient from the first 3D image data set comprises a position change of the patient which is captured by the 2D image.
3. The method as claimed in claim 1 , wherein the first image acquisition system comprises an MRI scanner.
4. The method as claimed in claim 1 , wherein the first image acquisition system comprises a 3D ultrasound image acquisition system.
5. The method as claimed in claim 1 , wherein the second image acquisition system comprises an X-ray angiography system.
6. An X-ray angiography system, comprising:
an input that receives a first and a second 3D image data set of a patient from an external image acquisition system, wherein the first 3D image data set comprises imaging of a part of the body of the patient comprising soft tissue, wherein one or more imaging parameters of the first image acquisition are selected for soft tissue imaging and further wherein the second 3D image data set comprises imaging of a part of the body of the patient comprising an skeletal structure, wherein one or more imaging parameters of the first image acquisition system are selected for skeletal imaging;
an X-ray acquisition device that creates a 3D X-ray image data set of the patient as a third 3D image data set, wherein the third 3D image data set comprises imaging of the part of the body of the patient comprising the skeletal structure imaged by the first image acquisition system;
a memory that stores the first, the second, and the third 3D image data set; and
an image processing device that determines a mapping rule for a coordinate transformation from the second 3D image data set to the third 3D image data set based on a registering of the skeletal structure having been respectively imaged by the first image acquisition system in the second 3D image data set and by the second image acquisition system in the third 3D image data set, and applies the mapping rule to the first image data set to generate a representation of the part of the body of the patient comprising soft tissue from the first 3D image data set related to the coordinate system of the second image acquisition system, and effective for registering the representation of the part of the body of the patient comprising soft tissue with a 2D image recorded by second image acquisition system.
7. The method as claimed in claim 1 , wherein the part of the body of the patient comprising soft tissue comprises a heart of the patient and the part of the body of the patient comprising the skeletal structure comprises a vertebral structure of the patient.
8. The X-ray angiography system as claimed in claim 6 , wherein the part of the body of the patient comprising soft tissue comprises a heart of the patient and the part of the body of the patient comprising the skeletal structure comprises a vertebral structure of the patient.