25 KB568 KB24 KB192920262011Cox, Robert W.Saad, Ziad S.Stare, JanezŠuput, DušanVovk, Andrejštevilka:6letnik:80str. 476-482ISSN:1318-0347COBISSID:28577497URN:URN:NBN:SI:doc-6L1F9ISVenSlovensko zdravniško društvoZdravniški vestnikanomalijediagnostikamagnetna resonancamožganislikovna diagnostikaUse of signatures to create probability maps of brain tissues in health and disease - a new diagnostic tool?| Uporaba statističnih podpisov za izdelavo verjetnostnih map zdravih in obolelih možganov - nov diagnostični pripomoček?|Segmentation of brain MRI into white matter, gray matter, cerebrospinal fluid,skull, and other categories is an integral part of MRI analysis. To date, most widely used segmentation approaches require the use of population-based spatial segmentation priors, mostly to improve robustness to shading artifacts and noise. Prior generation requires a set of segmented volumes from a population similar to the one to be studied, and an alignment approach for aligning brains from multiple subjects. Aim: In this paper we present a method for generating segmentation priors that is insensitive to noise and field bias and does not require registration to a template space. Methods: Our approach relies on using signatures, a set of local descriptive statistics, computed over multiple spatial scales. In the training process, signatures of each tissue are clustered into representative sub-classes. Representative signatures are the median of signatures in each subclass. In a new dataset, voxel signatures are compared to the set of representative signatures and tissue classification priors are generated using Bayesć rule and total probability. Results: These signature-based probability maps can replace spatially-based population priors in segmentation. We also show that signature similarity can be used interactively to delineate brain lesions, such as tumours, thereby facilitating diagnostic procedures. Conclusions: Voxel signatures consisting of spatial texture information across multiple scales, can be used either as simple similarity measure to select tissue of the same type or to create tissue prior probability maps that can be used in brain segmentation and in other clinically relevant proceduresTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaSlovensko zdravniško društvo