Abstract
Radiofrequency current energy can be used to ablate pathologic tissue. Through magnetic resonance imaging (MRI), real-time guidance and control of the procedure is feasible. For many tissues, resulting lesions have a characteristic appearance with two boundaries enclosing an inner hypo-intense region and an outer hyper-intense margin, in both contrast enhanced T1 and T2 weighted MR images. We created a model having two quadric surfaces and twelve-parameters to describe both lesion surfaces. Parameter estimation was performed using iterative optimization such that the sum of the squared shortest distances from segmented points to the model surface was minimized. The method was applied to in vivo image volumes of lesions in a rabbit thigh model. For all in vivo lesions, the mean signed distance from the model surface to segmented boundaries, accounting for the interior or exterior location of points, was approximately zero with standard deviations less than a voxel width (0.7 mm). For all in vivo lesions, the median absolute distance from the model surface to data was ≤ 0.6 mm for both surfaces. We conclude our model provides a good approximation of actual lesion geometry and should prove useful for three-dimensional lesion visualization, volume estimation, automated segmentation, and volume registration.
Original language | English (US) |
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Pages (from-to) | 360-367 |
Number of pages | 8 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5029 |
DOIs | |
State | Published - 2003 |
Externally published | Yes |
Event | Medical Imaging 2003: Visualization, Image-Guided Procedures and Display - San Diego, CA, United States Duration: Feb 16 2003 → Feb 18 2003 |
Keywords
- Deformable model
- Interventional magnetic resonance imaging
- Radiofrequency thermal ablation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering