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Segmenting Brain Tumors using Pseudo-Conditional Random Fields

Full Text: pcrf_cam1.pdf PDF
Other Attachments: posterDes_S38.ppt [Slides] PPT

Locating Brain tumor segmentation within MR (magnetic resonance) images is integral to the treatment of brain cancer. This segmentation task requires classifying each voxel as either tumor or non-tumor, based on a description of that voxel. Unfortunately, standard classifiers, such as Logistic Regression (LR) and Support Vector Machines (SVM), typically have limited accuracy as they treat voxels as independent and identically distributed (i.i.d.). Approaches based on random fields, which are able to incorporate spatial constraints, have recently been applied to brain tumor segmentation with notable performance improvement over i.i.d. classifiers. However, previous random field systems involved computationally intractable formulations, which are typically solved using some approximation. Here, we present pseudo-conditional random fields (PCRFs), which achieve accuracy similar to other random fields variants, but are significantly more efficient. We formulate a PCRF as a regularized discriminative classifier that achieves the robustness of an i.i.d. learner (such as LR and SVM) while also incorporating spatial dependencies is as effective as state-of-the-art random fields, but significantly more efficient Our empirical experiments demonstrate PCRF's effectiveness and efficiency in a real-world segmentation task (brain tumors from MR images), which involves non-trivial spatial dependencies.

Citation

C. Lee, S. Wang, M. Brown, A. Murtha, R. Greiner. "Segmenting Brain Tumors using Pseudo-Conditional Random Fields". Medical Image Computing and Computer-Assisted Intervention, pp 359-366, September 2008.

Keywords: brain tumor, BTAP, machine learning, random fields, medical informatics
Category: In Conference
Web Links: DOI

BibTeX

@incollection{Lee+al:MICCAI08,
  author = {Chi-Hoon Lee and Shaojun Wang and Matt Brown and Albert Murtha and
    Russ Greiner},
  title = {Segmenting Brain Tumors using Pseudo-Conditional Random Fields},
  Pages = {359-366},
  booktitle = {Medical Image Computing and Computer-Assisted Intervention},
  year = 2008,
}

Last Updated: April 28, 2012
Submitted by Russ Greiner

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