Inobitec DICOM Viewer

6.4. Building Segmented Structures with Contours

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Functionality is available in the Pro edition
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6.4.1 General Information

Contours are used for segmentation of the organs whose density is comparable with the density of the surrounding tissue, e.g the heart, the liver, and joints. In such cases, it is hard to see the boundaries of the region. Hence, the automatic segmentation procedure cannot be applied.

Contours are built on sections in the MPR reconstruction tab. If the 3D view window is opened in the tab, the segmented structure created is simultaneously shown on the volume model.

To customize the contours display, press the arrow on the right-hand side of the Contour segmentation PIC button and provide the required parameters in the menu.

  • To enable/disable the contours display on the volume model, check/uncheck the box next to the Show contours in 3D option. By default, the option is enabled.

  • To enable/disable the synchronization point display when the user hovers over the contour, check/uncheck the box next to the Show syncpoint option. By default, the option is disabled.

6.4.2 Building a Segmented Structure with Contours

To build a segmented structure with contours, proceed as follows:

  1. Open the study in the MPR Reconstruction tab. Create an empty structure and configure the mask by setting the tissue density. For the details on mask creation, see Section 6.2.1.

  2. Activate the Contour segmentation PIC tool by clicking the left/right/middle mouse button. To continue work with this tool, use the button with which the tool was activated. To learn more about tool control, see Section 1.14.
    Build the contour in one of the following ways:

    • Building contours manually. Build the contour around the chosen area while holding the mouse button. To finish the procedure and close the contour, release the mouse button. To cancel the contour that has not been closed, press Esc on the keyboard while holding the button.

    • Building contours with an isoline. Move the cursor around the selected area while holding the Shift button on the keyboard. Under the cursor, you will see an isoline characterized by even points density. You can only see an isoline on the surfaces where a contour can be built. To build a contour with an isoline, click the mouse button.

  3. Go to the next slice and draw a contour around the selected area. Contours are only built on parallel planes. Contours are used to create a segmented structure with regard for the edit mask. You need at least two contours to build a segmented structure.

Segmented structures may not be shown on the sections with the first and the last contour.

Contours projections are shown on perpendicular sections of the MPR reconstruction tab, in the 3D view window and on the sections where they were built. If a slice is not perpendicular to the contour plane, the projection of this contour is not shown.

When you hover over the contour line, it is highlighted in all the windows of the tab. If the Show syncpoint option is enabled, the synchronization point is displayed on the contour, in the crosshairs under the cursor.

If you click the mouse button while the cursor is on the contour line in the 3D view window, you will go to the section with this contour in the MPR reconstruction window.

6.4.3 Work with Contours

DICOM Viewer provides for the following actions with contours:



Click OK to apply the settings or Cancel to cancel.