An Efficient Algorithm for Multiple Sclerosis Segmentation from Brain MRI

We propose a novel method for the segmentation of Multiple Sclerosis (MS) lesions in MRI. The method is based on a three-step approach: first a conventional k-NN classifier is applied to pre-classify gray matter (GM), white matter (WM), cerebro-spinal fluid (CSF) and MS lesions from a set of prototypes selected by an expert. Second, the classification of problematic patterns is resolved computing a fast distance transformation (DT) algorithm from the set of prototypes in the Euclidean space defined by the MRI dataset. Finally, a connected component filtering algorithm is used to remove lesion voxels not connected to the real lesions. This method uses distance information together with intensity information to improve the accuracy of lesion segmentation and, thus, it is specially useful when MS lesions have similar intensity values than other tissues. It is also well suited for interactive segmentations due to its efficiency. Results are shown on real MRI data as wall as on a standard database of synthetic images.

[1]  Alan C. Evans,et al.  BrainWeb: Online Interface to a 3D MRI Simulated Brain Database , 1997 .

[2]  Keinosuke Fukunaga,et al.  A Branch and Bound Algorithm for Computing k-Nearest Neighbors , 1975, IEEE Transactions on Computers.

[3]  J. Sack,et al.  Handbook of computational geometry , 2000 .

[4]  G. Borgefors Distance transformations in arbitrary dimensions , 1984 .

[5]  Forest Baskett,et al.  An Algorithm for Finding Nearest Neighbors , 1975, IEEE Transactions on Computers.

[6]  Piet W. Verbeek,et al.  An Efficient Uniform Cost Algorithm Applied to Distance Transforms , 1989, IEEE Trans. Pattern Anal. Mach. Intell..

[7]  Peter E. Hart,et al.  Nearest neighbor pattern classification , 1967, IEEE Trans. Inf. Theory.

[8]  Atsuyuki Okabe,et al.  Spatial Tessellations: Concepts and Applications of Voronoi Diagrams , 1992, Wiley Series in Probability and Mathematical Statistics.

[9]  Benoit M. Macq,et al.  Fast k-NN classification with an optimal k-distance transformation algorithm , 2000, 2000 10th European Signal Processing Conference.

[10]  Qiyuan Jiang,et al.  An improved method for finding nearest neighbors , 1993, Pattern Recognit. Lett..

[11]  Simon K. Warfield,et al.  Fast k-NN classification for multichannel image data , 1996, Pattern Recognit. Lett..

[12]  R P Velthuizen,et al.  MRI: stability of three supervised segmentation techniques. , 1993, Magnetic resonance imaging.

[13]  Richard O. Duda,et al.  Pattern classification and scene analysis , 1974, A Wiley-Interscience publication.

[14]  Ingemar Ragnemalm,et al.  The Euclidean distance transform in arbitrary dimensions , 1992, Pattern Recognit. Lett..

[15]  Ron Kikinis,et al.  Adaptive, template moderated, spatially varying statistical classification , 2000, Medical Image Anal..

[16]  Franz Aurenhammer,et al.  Voronoi Diagrams , 2000, Handbook of Computational Geometry.

[17]  P. Danielsson Euclidean distance mapping , 1980 .