Intensity non-uniformity correction in multi-section whole body MRI
نویسندگان
چکیده
As whole body MRI (WB-MRI) gains currency, the data this class of technique generates presents new challenges for the imaging community. One acquisition protocol currently being applied with considerable success entails imaging the subject in a number of successive coronal sections, resulting in a high resolution, gap free, full body acquisition. However this technique often results in considerable greylevel offsets between adjacent coronal sections. To make the images suitable for the application of automated image analysis procedures these discontinuities in the grey data must be alleviated. We examine the issues related to this problem, and present a solution based on histogram rescaling, which is designed to correct for the non-uniformities while preserving the integrity of the data histogram so that it can be used robustly in later processing steps. The final datasets reconstructed from the resampled coronal sections exhibit superior greyscale homogeneity, visually and in statistical measures, and the image segmentation results achieved using this corrected data are consistently more robust and more accurate than those arrived at using the original raw data. The approach has been tested and successfully validated on a database of sixty two WB-MRI datasets.
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