8.3. Building Contours

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Functionality is available in a separate module which is activated in the Pro edition for an extra fee
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The functional parameters of the left and the right ventricles are calculated on the basis of the contours built. Contours can be built separately for each slice and phase in the window with the SAX merged series. The contour boundaries are shown as points on the slices in the window with the merge LAX series. If two or more contours were built for one phase, the points can be connected by segments. You cannot build contours in the window with a LAX merged series.

To simplify the process of building contours, we recommend enabling the display of slices scout lines in the window selected (see Section 2.25).

8.3.1 Building Contours Manually

You can use the following tools to build contours manually:

Endocardial LV contour ;

Epicardial LV contour ;

Endocardial RV contour ;

Epicardial RV contour .

The choice of the tool depends on the region of interest and the results of the analysis required.

To build a contour, proceed as follows:

Open the study in the Cardiac function analysis tab (see Section 8.1).
Activate one of the contour building tools with the left, right, or middle mouse button. To continue work with the same tool, use the button with which the tool was activated. For details on tool management, see Section 1.14. Build the contour in one of the following ways:
- building contours manually. In the window with the SAX merged series, build a contour around the selected area while holding the button with which the tool was activated. To complete the contour, release the mouse button. To cancel the contour that has not been closed, click Esc on the keyboard while holding the mouse button;
- building contours with an isoline. Move the cursor around the selected area while holding the Shift button on the keyboard and the mouse button with which the tool was activated. Under the cursor, you will see an isoline. You can see an isoline only on the slices where a contour can be built. To build a contour with an isoline, release the mouse button with which the tool was activated.
Go to the next slice and contour the selected area.
After you have built the required contours, click the Start analysis button to go to the results of parameters assessment (see Section 8.4).

Figure 8.3: The Left ventricle epicardium and endocardium contours are shown in the SAX window, and the contour boundaries on the slices are shown in the LAX window

If there is a contour built with the current tool on the current slice, you cannot build a new contour here. You can only edit or delete the existing contour (see Section 8.3.4).

8.3.2 Evaluating the Left Ventricle Extension

To evaluate the left ventricle extension, you need the SAX and the LAX merged series to be loaded to the Cardiac analysis tab (see Section 8.1).

To evaluate the left ventricle extension, proceed as follows:

Open the study in the Cardiac function analysis tab (see Section 8.1).
Activate the LV extension boundaries tool with the left, right, or middle mouse button. To continue work with the same tool, use the button with which the tool was activated. For details on tool management, see Section 1.14.
In the window with the SAX merged series, choose the slice for the upper plane of the mitral valve and mark a point in the center of the mitral valve.
Go to the slice corresponding to the left ventricular apex and mark a point in the center of the apex.

When you mouse over a point in the window with the SAX merged series, you see a pop-up tip with the type of the point, Mitral or Apex.

In the window with the LAX merged series, the left ventricle extension is marked with a line (Fig. 8.4).

Figure 8.4: Left ventricle extension shown in the window with the LAX merged series

In multiphase series, the left ventricle extension may be determined for each phase.

8.3.3 Contouring the Left Ventricle Endocardium and Epicardium Automatically

To contour the left ventricle endocardium and epicardium automatically, proceed as follows:

Open the study in the Cardiac function analysis tab (see Section 8.1).
Determine the left ventricle extension (see Section 8.3.2) for the End Diastole (ED) and End Systole (ES) phases.
Click the Auto contouring button on the toolbar for cardiac function analysis.

Automatic contouring of the left ventricle endocardium and epicardium are performed in the window with the SAX merged series for all the phases with the left ventricle extension and all the slices within the extension. The contour boundaries are shown on the slices in the window with the LAX merged series (Fig. 8.5).

The program algorithm builds the epicardium contour on the basis of the left ventricle endocardium contour. If the program fails to build the endocardium contour on a slice or if an error is made while contouring, it will be impossible to build the epicardium contour on this slice or a similar error will be made.

Attention! If a part of the atrium is present on the mitral valve slice, it may be captures while contouring.

Figure 8.5: Automatic contouring of the left ventricle

To rebuild all the contours, press the arrow on the right-hand side of the Auto contouring button and select Rebuild contours.

During automatic contouring, it is possible that tissues may be captured by the contour in error. Check that the contours are drawn correctly and edit the contours manually if necessary.

To go to the results of parameters assessment, click the Start analysis button (see Section 8.4).

8.3.4 Actions with Contours

The DICOM Viewer provides an opportunity to perform the following actions with contours:

editing. Mouse over the selected contour. When the cursor is placed on the contour, the contour is highlighted. Click the mouse button in the place where you want to edit the contour and build a new contour while holding the mouse button. To complete the contour, release the mouse button;

deleting a contour. Mouse over the selected contour, click the right mouse button, and select the Remove contour option on the context menu;

deleting all the contours of the same type. Click the arrow on the right-hand side of the Remove all cardiac contours button. On the menu, select the type of contours you want to delete from all the slices;

deleting all the contours. To delete all the contours, click the Remove all cardiac contours button. All the contours on all the slices in the window with the SAX merged series will be deleted;

deleting the extension boundaries. Place the cursor on one of the points used for evaluating the LV extension. The point will be highlighted. Click the right-hand mouse button and select the Remove extension boundaries option on the context menu.