Segmenting a 4D Heart Model

Follow these steps to create and segment a 4D heart model from your image series.

1. Create a New Structure

• Open the Models tab in the Controller Menu.

• Create a new structure.

2. Access the Image Series

• Open the Images tab.

• Scroll to the bottom to locate the Time Series Settings.

This section allows you to:

• Set the image series to Static (manually cycle through phases), or

• Set it to Dynamic (automatically cycle through phases at adjustable speeds).

To segment a 4D heart, you’ll need to segment all phases in the image series.

For efficiency, set the series speed to its maximum before beginning.

3. Begin Segmenting

• Open the Stylus Menu and select the Add Tool.

• On the surface plane, ensure Use Threshold and Display Threshold are both enabled.

• Adjust the threshold to match the contrast-filled heart chambers.

• Begin segmenting — you’ll see the segmentation applied across all image phases.

• Continue cycling through the image volume while segmenting until all desired anatomy is built.

Tip: Segmentation can also be performed in 3D, though this can be computationally demanding and may cause temporary performance lag.

4. Clean Up the Segmentation

Once the 4D blood pool is segmented, you can clean up floating anatomy for a smoother model.

1. Open the Images tab and set Time Series Settings to Static.

2. Open the Stylus Menu and select the Select-Connected Tool.

3. While squeezing the index finger trigger on your dominant hand, tap the blood volume you want to select.

• A white film will appear around the model, indicating the selected blood volume.

4. When the selection is complete, tap Delete Unselected on the surface plane.

• This removes all floating anatomy and yields a tidier blood volume.

5. Repeat this process for each phase.

5. Build a Shell Around the Blood Volume

1. Open the Operations tab in the Controller Menu.

2. Under Single Structure Operations:

• Select the blood volume as the structure.

• Change the operation to Shell.

• Set your desired shell thickness.

3. Before executing, ensure Apply to All Phases is enabled.

4. Press Execute.

A new structure will appear, and you’ll see it listed in the Models tab.