The relate option lets you cross-reference a particular point on a Volume Rendered image with its relevant location on the MPR reference images. This option is only available when you look at all four images on screen at the same time.
1. Click Relate 
.
2. On the Volume Rendered image, click the point you want to relate.
The cross lines on the MPR images move to show the relevant point on the MPR slices.
NOTE: Since a Volume Rendered image is displayed as a volume rather than a plane, when you use the relate operation in Volume Rendering there is a conceptual issue of where in the 3D space you have clicked. As a result, the final result shown may sometimes be displayed incorrectly.
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