This algorithm can combine the procedures of segmentation process and nonlinear grey scale mapping.
In contrast, in DXA analysis, it is easy to make an error during manual procedures of segmentation of the thigh from the trunk.
In this study, an image processing scheme composed of segmentation procedures based on anisotropic diffusion and shape classification is presented.
Robustness over field-to-field or cell-to-cell intensity variations can be increased by using methods to automatically compute thresholds instead of constant values, which is essential for automation of segmentation procedures in a high-throughput context.
The procedure included segmentation of the white matter using a grow-region function, the smooth covering of a sphere around the segmented region, and the expansion of the reconstructed white matter into the grey matter.
The Free Surfer procedure for lesion segmentation combines the initial standard segmentation with an extension of the subcortical segmentation procedure that incorporates information from a co registered T2 and PD image for the segmentation of signal abnormalities within the white matter.
All voxels outside the subject's head (air/background) were explicitly modelled with another prior (noted "other" in Figure 3B); this is included by default in the unified segmentation procedure of SPM8 [5].
The present data support the outline of the segmentation procedure of Insausti, Juottonen, et al. (1998) also in agreement with Pruessner et al. (2002).
This change caused more difficulties in the segmentation procedure of abdominal organs, but it did not affect the results or conclusions of the experiments.
T1 scans were segmented to define the border between gray and white matter with the automatic segmentation procedure of BrainVoyager QX and complemented with manual improvements where necessary.
All functional volumes were spatially realigned, unwarped, normalized to Montreal Neurological Institute (MNI) space using the unified normalization-segmentation procedure of SPM5, and smoothed with an isotropic 6-mm full-width at half-maximum Gaussian kernel, with resulting voxel size of 2 × 2 × 2 mm.
