Paper Info
Title
Nonrigid registration of dynamic breast F-18-FDG PET/CT images using deformable FEM model and CT image warping
Abstract
This study was undertaken to correct for motion artifacts in dynamic breast F-18-FDG PET/CT images, to improve differential-image quality, and to increase accuracy of time-activity curves. Dynamic PET studies, with subjects prone, and breast suspended freely employed a protocol with 50 frames, each 1-minute long. A 30 s long CT scan was acquired immediately before the first PET frame. F-18-FDG was administered during the first PET time frame. Fiducial skin markers (FSMs) each containing similar to 0.5 mu Ci of Ge-68 were taped to each breast. In our PET/PET registration method we utilized CT data. For corresponding FSMs visible on the 1st and nth frames, the geometrical centroids of FSMs were found and their displacement vectors were estimated and used to deform the finite element method (FEM) mesh of the CT image (registered with 1st PET frame) to match the consecutive dynamic PET time frames. Each mesh was then deformed to match the 1st PET frame using known FSM displacement vectors as FEM loads, and the warped PET time-frame volume was created. All PET time frames were thus nonrigidly registered with the first frame. An analogy between orthogonal components of the displacement field and the temperature distribution in steady-state heat transfer in solids is used, via standard heat-conduction FEM software with "conductivity" of surface elements set arbitrarily significantly higher than that of volume elements. Consequently, the surface reaches steady state before the volume. This prevents creation of concentrated FEM loads at the locations of FSMs and reaching incorrect FEM solution. We observe improved similarity between the 1st and nth frames. The contrast and the spatial definition of metabolically hyperactive regions are superior in the registered 3D images compared to unregistered 3D images. Additional work is needed to eliminate small image artifacts due to FSMs.
Year
DOI
Venue
2007
10.1117/12.710014
PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE)
Keywords
Field
DocType
nonrigid 3D image registration,dynamic breast PET/CT,differential images,deformable FEM soft tissue model
Computer vision,Displacement field,PET-CT,Fiducial marker,Image warping,Computer science,Finite element method,Software,Artificial intelligence,Computed tomography,Centroid
Conference
Volume
ISSN
Citations 
6512
0277-786X
0
PageRank 
References 
Authors
0.34
2
9
Name
Order
Citations
PageRank
Alphonso Magri121.85
Andrzej Krol2298.49
Mehmet Z. Unlu363.20
Edward D. Lipson422.92
James A. Mandel563.54
wendy mcgraw600.34
Wei Lee732.60
Ioana L. Coman8377.28
David H. Feiglin9188.32