Imaging method, controller and imaging system, for monitoring a patient post EVAR

A controller for imaging a stent following endovascular aneurysm repair with a bifurcated stent graft having a stent body and two stent legs defining a bifurcation point at a junction of the two stent legs, wherein the controller is adapted to:

• receive a previously generated first 3D volume scan of the bifurcated stent graft in situ;
• acquire a second 3D volume scan of the bifurcated stent graft in situ;
• generate one or more fiducial markers in a first image derived from the first scan and in a second image derived from the second scan, wherein one of the fiducial markers is the bifurcation point;
• extract a rigid 3D transform mapping based on the one or more fiducial markers;
• apply a registration to the first and second scans based on the 3D rigid transform between the first and second images;
• derive a size value at the same location in the aneurysm from the first and second scans, where the same location is determined with reference to the registered first and second images of the bifurcated stent graft;
• and
• compare the size value from the first and second scans to assess a change in size of the aneurysm between the first and second scans.

An imaging system, comprising:

• a beamformer;
• a display device;
• a controller;
• and
• a tangible, non-transitory computer readable medium, which stores instructions, which when executed by the controller, cause the controller to:
• receive a previously generated first 3D volume scan of a stent in situ;
• acquire a second 3D volume scan of the stent in situ;
• generate one or more fiducial markers in a first image derived from the first scan and in a second image derived from the second scan, wherein one of the fiducial markers is a bifurcation point;
• extract a rigid 3D transform mapping based on the one or more fiducial markers;
• apply a registration to the first and second scans based on the 3D rigid transform between the first and second images;
• derive a size value at the same location in an aneurysm from the first and second scans, where the same location is determined with reference to the registered first and second images of the stent;
• and compare the size value from the first and second scans to assess a change in size of the aneurysm between the first and second scans.