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ROI and Contour Level Properties

The Contours section contains the list of the contours defined in the current slice of the image series for the VOI selected in the VOIs list. All contours belonging to a VOI in a single plane form together the planar ROI. When

The arrow buttons on top of the list allow changing the location of the selected contour in the list.

Each contour has properties, which can be changed with the buttons on the right of the list.

Plus Contour: This buttons sets all contours selected in the list to + in the operation column O. The meaning of a + contour is that the pixels enclosed by the contour are included in the statistics. This operation mode is equivalent to the OR set operation.

Minus Contour: This buttons sets all contours selected in the list to -. The meaning of a - contour is that all enclosed pixels are excluded from the statistics. This operation mode is equivalent to the AND NOT set operation.

Cardiac example illustrating how a negative inner contour can be used to create a hollow VOI.

CAUTION: The first contour in the list needs to be a + contour.

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Closed Contour : The last vertex is connected to the first vertex, defining the VOI as the inner of the polygon.

Line Contour : Only the pixels along the trajectory from the first to the last contour vertex are included into the VOI.

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Vertices Contour : This is the default mode, whereby vertices are connected by straight lines.

B-Spline Contour : After contours have been defined, they can be switched to B-Spline mode, whereby a spline function is calculated which passes through all vertices. Initially the lined will minimize the bending energy, but there are control handles at each vertex to change the boundary conditions.

Similar to the VOI level, the size and angle can be changed on the contour level by two approaches.

ROI Properties

All contours belonging to a VOI in a single plane form together the planar ROI. The properties of all ROI contours can be changed at once by the button, which shows the dialog window below. It allows changing the Location, Size and Rotation angles of the ROIs. The translation and scaling operations are restricted within the contour plane plane, and the to rotation around the orthogonal.

Contour Properties

The properties of individual contours can be changed by the button, which works similar as the button. It additionally offers changing the Contour name.