Multi-Planar Reconstruction (MPR)

You can interactively resample an existing image to have different numbers of slices, rows, and columns, different pixel sizes and fields of view, and different orientations of the slices using Jim's MPR tool images). Jim uses sophisticated resampling techniques to give the best possible quality in the re-sampled image.

To interactively resample an existing image, first load that image into Jim's display window, then select Multi-Planar Reconstruction from the Organise menu: organise_mpr of the main display frame.

This brings up:


The MPR tool shows the current loaded image, with the extent of the resample volume indicated by the extent of the yellow boxes. The image in the main display also shows the currently-defined resample volume as a cuboid superimposed on the loaded image. Solid lines are above the image slice, and dashed lines are below the image slice.


To help you orientate yourself, there are three coloured blobs (red, green and blue) on three edges of the cuboid that defines the resampling volume. These blobs can be seen both in the MPR tool, and in the main display.



Defining the Resample Volume

You can set the properties (size, number of samples and orientation) of the re-sampled image by:

As you move and rotate the handles, you will see an indication of the position that the new sample volume will take. As you release the mouse button, or type in new values for the pixel sizes or number of pixels (and press return), the resampling volume is redefined, and the views of the image are updated.

When you are happy with the redefined sample volume, you can resample the original image with these settings to create a new image. Click the resample_button button to create the new dataset. The new image will be of the same type as the input image. The new image can either be saved to disk, or loaded into Jim depending on your selection:


If you selected "Save to disk", Jim will prompt you for a new image file name for the re-sampled image.

Type of Interpolation

If the pixel size is different from than the original in any dimension, or if the re-sampled image planes are not parallel to original planes, then the image must be interpolated to obtain the new intensity values.


You can select from the three types of interpolation:

Saving and Loading the MPR Geometry

You may want to save the geometry of the MPR volume and apply the same resampling volume to another image. To save the geometry of the MPR volume, select "Save Geometry..." from the File menu:

Save the MPR volume geometry to disk

This will bring up a File Chooser for you to select an XML file into which the geometry is to be saved.

After loading another image into Jim's display, to load this MPR geometry, select "Load Geometry..." from the File menu:

Load the MPR volume geometry from an XML

This will set the resampling volume and resampled pixel sizes exactly the same as when you saved the geometry.

Note: if the newly-loaded image does not have the same field-of-view and slice orientations/positions as the original image on which the geometry was saved, the MPR volume will not contain the same anatomy.

3-D Cut-Away View

The bottom right corner of the MPR toolkit shows a 3-D view of the orthogonal planes passing through the centre of the current resample volume.


You can rotate this view of the resample volume by clicking and dragging the mouse in this panel.

Resizing the Panes

The four panes of the MPR tool can be resized to give a more detailed view of one aspect of the resampling. Simply drag the vertical and horizontal dividers between the panes.


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