Registering intra-operative image data sets with pre-operative 3D image data sets on the basis of optical surface extraction

1. A method for registering an intra-operative image data set with a pre-operative 3D image data set for a medical examination, comprising:

providing a pre-operative 3D image data set for a medical examination, said data set including information descriptive of a surface along a feature of a patient such that an image of the surface is obtainable from the data set;

obtaining a pre-operative surface mask for the surface from the pre-operative 3D image data set;

positioning an optical 3D sensor system to provide a side view of the surface of the feature;

calibrating the optical 3D sensor system with respect to an intra-operative imaging modality;

illuminating the surface with a light pattern such that the side view of the illuminated surface indicates displacement of lines in the pattern along the feature;

detecting an area of interest including the illuminated surface of the feature with the optical 3D sensor system and obtaining an intra-operative surface mask of the feature based on data acquired with the optical 3D sensor system;

recording the area of interest with the intra-operative imaging modality at least partly containing the intra-operative surface mask to obtain the intra-operative image data set;

registering the intra-operative surface mask with the pre-operative surface mask;

determining a mapping specification between the intra-operative image data set and the pre-operative 3D image data set based on the calibration of the optical 3D sensor system with the intra-operative imaging modality and the registration of the intra-operative surface mask with the pre-operative surface mask; and

overlaying the intra-operative image data set with the pre-operative 3D data set based on the mapping specification.

2. The method as claimed in claim 1 , wherein the intra-operative image data set is a 2D fluoroscopic image of an x-ray C-arm.

3. The method as claimed in claim 1 , wherein the intra-operative imaging modality is selected from the group consisting of: an fMRT device, a PET device, a SPECT device, and a functional mapping modality.

4. The method as claimed in claim 3 , wherein the functional mapping modality is taken from the group consisting of an EEG and an MEG.

5. The method as claimed in claim 1 , wherein the pre-operative 3D image data set originates from a morphological imaging modality selected from the group consisting of: an MRT device, a CT device, a C-arm rotation angiography device, and a 3D ultrasound device.

6. The method as claimed in claim 1 , wherein the step of detecting is undertaken by illuminating and observing the surface of the area of interest via a white light projector providing a pattern of stripes on the surface, and features of the surface are computed based on displacement of the stripes as viewed in the side view.

7. The method as claimed in claim 6 , wherein the detection is undertaken within one second at a resolution of up to 200 μm.

8. The method as claimed in claim 7 , wherein the detection is undertaken before the intra-operative recording or periodically during the intra-operative recording.

9. The method as claimed in claim 1 , wherein a movement field of the area of interest is computed and used to reduce a movement artifact in the intra-operative recording or to improve a resolution of the recording.

10. A method for registering an intra-operative image data set with a pre-operative 3D image data set for a medical examination, comprising:

calibrating an optical 3D sensor system with respect to an intra-operative imaging modality;

positioning the optical 3D sensor system to generate a side view of a surface along an area of interest of a patient by illuminating the surface with a light pattern such that the side view of the illuminated surface indicates displacement of lines in the pattern along the area of interest;

obtaining an intra-operative surface mask corresponding to the surface based on side view data acquired with the optical 3D sensor system wherein the surface mask is generated within one second at a resolution of up to 200 μm via a white light projector illuminated with a pattern of stripes, based on a displacement of the stripes as detected in the side view data;

recording an image of the surface along the area of interest with the intra-operative imaging modality at least partly containing the intra-operative surface mask to obtain the intra-operative image data set;

computing another image of the surface along the area of interest from the pre-operative 3D image data set to obtain a pre-operative surface mask;

registering the intra-operative surface mask with the pre-operative surface mask;

determining a mapping specification between the intra-operative image data set and the pre-operative 3D image data set based on the calibration of the optical 3D sensor system with the intra-operative imaging modality and the registration of the intra-operative surface mask with the pre-operative surface mask; and

overlaying the intra-operative image data set with the pre-operative 3D data set based on the mapping specification.