Coregistration

The coregistered images are displayed side by side with a linked cursor indicating spatial correspondence or may be overlaid or fused using the gray scale or color display. The spatial correspondence by coregistration between the... 

Potential pitfalls in the computation of CBF using deconvolution methods include patient motion and partial volume averaging, which can cause underestimation of the AIF(f). Image coregistration software to correct for patient motion and careful choice of ROIs for the AIF can minimize these pitfalls. 

An early report from our group indicated that, in the absence of early recanalization, CTA-Sl typically defines minimal final infarct size and, hence, like DWI and thresholded CBF maps (Fig.5.5, 5.6), can be used to identify infarct core in the acute setting [34] (Figs. 5.5, 5.6). Coregistration and subtraction of the conventional, unenhanced CT brain images from the axial, post contrast CTA source images should result in quantitative blood volume maps of the entire brain [15, 27, 70]. CTA-SI subtraction maps, obtained by coregistration and subtraction of the unenhanced head CT... 

Schellingerhout, D., et al.. Coregistration of head CT comparison studies assessment of clinical utility. Acad Radiol,... 

In practice there are many ways in which we can attempt to achieve this and the technique selection will depend on the imaging modalities involved, the reason for coregistering the images and the accuracy of coregistration required for the analysis technique to be employed. 

Fig. 8.7. Subtraction images of two 3D MRI brain scans performed in a healthy individual. The brains in the two scans have been coregistered and subtracted resulting in complete loss of structural information in the brain. Note that the peripheral tissues are clearly seen since these were removed from one data set prior to coregistration...

The most commonly applied technique for image coregistration is to estimate the transforma-... 

The techniques of automated image coregistration were first applied to medical data sets to improve the stability of data analysis in functional magnetic resonance imaging (fMRI). Functional MRI tech-... 

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