发明名称 |
FIDUCIAL-LESS TRACKING WITH NON-RIGID IMAGE REGISTRATION |
摘要 |
A method and system is presented for tracking patient motion in image guided surgery, using skeletal reference structures instead of fiducial markers. A non-rigid 2D/3D image registration is performed between pre-operative 3D scan data and intra-operative 2D images. The CT numbers are modified to compensate for the difference between the ratio of bone-to-tissue attenuation at the CT scan energy level, and the X-ray projection energy level. DRRs (102) are generated from the modified CT numbers. An ROI(104), within which the image registration is restricted, is defined within the DRRs by calculating a modified Shannon entropy for each image, and seeking the region in which the image entropy is maximized. The DDRs and 2D images are enhanced (115)by applying a top hat filter to increase the visibility of the skeletal structures. The 2D/3D transformation parameters are determined by generating a full motion field that accounts for non-rigid motions and deformations. The full motion field is derived by estimating a plurality of local motion fields, using multi-level block matching and a similarity measure based on pattern intensity. |
申请公布号 |
WO2006011925(A3) |
申请公布日期 |
2006.12.21 |
申请号 |
WO2005US08659 |
申请日期 |
2005.03.15 |
申请人 |
ACCURAY, INC.;FU, DONGSHAN;KUDUVALLI, GOPINATH |
发明人 |
FU, DONGSHAN;KUDUVALLI, GOPINATH |
分类号 |
G06K9/00 |
主分类号 |
G06K9/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|