PURPOSE MRI has become an attractive tool for tumor motion management. Current MR-compatible phantoms are only capable of reproducing translational motion. This study describes the construction and validation of a more realistic, MRI-compatible lung phantom that is deformable internally as well as externally. We demonstrate a radiotherapy application of this phantom by validating the geometric ...

Following the success of applying deformable models to feature extraction, a natural next step is to apply such models to pattern classiication. Recently, we have cast a deformable model under a Bayesian framework for classiication, giving promising results. However, deformable model methods are computation-ally expensive due to the required iterative optimization process. The problem is even m...

This paper aims to make a brief survey on the current segmentation algorithms used for medical images. Instead of describing the detailed procedures, we will summarize their main ideas, enumerate their merits and drawbacks and discuss their possible applications. The algorithms are classified into three main categories: threshold-based models, pattern recognition models and deformable models. D...

We are interested in producing a 3D deformable model of the human hand, for use in a tracking application. Statistical methods can be used to build such a model from a set of training examples; however, a key requirement for this is the collection of landmark coordinate data from these training examples. To produce a good model, hundreds of landmarks are required from each example; collecting t...