Editing Contour Shapes

The following tools are available for adjusting the shape of completed contours.

Moving Individual Vertices

When the Edit Mode is active, the user can click at individual contour vertices and then drag them to more appropriate positions. Clicking at contours from different VOIs will automatically select the corresponding VOI in the VOIs list.

Deleting Vertices

The eraser of the PMOD VOI tool can have different shapes and sizes which may be selected from the option list close to the eraser button.

To delete pixels from a contour VOI:

1. Select the affected contour by selection in the VOIs and Contours list.
2. Activate the eraser button .
3. Drag the eraser shape against the contour vertices which should be removed.
   

Erase 2D and erase 3D IH

The 2D eraser of the PMOD VOI tool is a circle which size can be selected from the option list:

To delete parts from a contour VOI:

1. Select the affected VOI by selection in the VOIs list.
2. Activate the 2D eraser button .
3. Click the eraser shape on the ROI area which should be removed.
   

The Interactive 3D removal is based on a sphere region growing algorithm. Initially, the area to be excluded from the VOI need to be located. Then the mouse button need to be clicked and held until the 'growing' sphere completely deletes the area of interest. After completion, the removal can still be extended simply by click+hold. The 3D removal based on region growing continues from the new point.

Inserting Vertices

It is also possible to insert vertices at any location into contours. As soon as the insertion tool is activated , the cursor shape changes accordingly. The contour to be edited can be selected by clicking at a vertex point, or by selection in the VOIs and Contours list. The segment into which a new vertex is inserted is determined by the vertex at which the user clicks, and is indicated by the emphasized vertices at both ends. When moving the cursor, the prospective two new segments are indicated by two faint lines. When the user clicks. the vertex is placed and the two new segments added. This procedure will continue for one of the created segments. To modify a different part of the contour please click at one of the vertices there. Note that the vertex locations cannot be changed in the insertion mode.

Shape Deformations

For the shape adjustment of densely populated contours a dedicated hammer tool is available. Similar to the eraser tool it can be configured for different sizes.

To change the contour shape with the hammer tool:

1. Select the affected contour by selection in the VOIs and Contours list.
2. Activate the hammer tool .
3. Drag the circular shape towards the contour vertices which are pushed radially away.