Abstract
Magnetic resonance imaging (MRI) is commonly employed for the depiction of softtissues, most notably the human brain. Computer-aided image analysis techniques lead toimage enhancement and automatic detection of anatomical structures. However, theintensity information contained in images does not often offer enough contrast to robustlyobtain a good detection of all internal brain structures, not least the deep gray matternuclei. We propose digital atlases that deform to fit the image data to be analyzed. In thisapplication, deformable atlases are employed for the detection and segmentation of brainnuclei, to allow analysis of brain structures. Our fully automatic technique is based on acombination of rigid, affine and non-linear registration, a priori information on keyanatomical landmarks and propagation of the information of the atlas. The Internet BrainSegmentation Repository (IBSR) data provide manually segmented brain data. Usingprior anatomical knowledge in local brain areas from a randomly chosen brain scan(atlas), a first estimation of the deformation fields is calculated by affine registration. Theimage alignment is refined through a non-linear transformation to correct thesegmentation of nuclei. The local segmentation results are greatly improved. They arerobust over the patient data and in accordance with the clinical ground truth. Validationof results is assessed by comparing the automatic segmentation of deep gray nuclei by theproposed method with manual segmentation. The technique offers the accuratesegmentation of difficultly identifiable brain structures in conjuncture with deformableatlases. Such automated processes allow the study of large image databases and provideconsistent measurements over the data. The method has a wide range of clinicalapplications of high impact that span from size and intensity quantification tocomprehensive (anatomical, functional, dynamic) analysis of internal brain structures.
Original language | English |
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Title of host publication | Brain Mapping and Diseases |
Publisher | Nova Science Publishers Inc |
Pages | 179-196 |
Number of pages | 18 |
ISBN (Print) | 9781611220650 |
Publication status | Published - 1 Jan 2011 |
Keywords
- Atlas
- Brain
- Deformation
- Gray matter nuclei
- MRI
- Registration
- Segmentation