Working with Segments

Working with Segments

After a method produces results, manage them in the Select segments list.

The Segment List

Each entry in Select segments shows:

• The segment name
• An eye button that toggles the segment’s visibility in the 3D view

Click a segment name to select it. Selecting an entry makes it the active segment for further actions.

Merging Segments

To combine multiple segments into one:

1. Select two or more segments in the list
2. Click Merge selection

The selected segments are merged into a single anatomy.

Create a Simulation Project

When the segmentation (and optional CleanUp) is ready, send the anatomy to a simulation project so it can be used by the lung analysis tools or the engineering simulation workflow. The same dialog also works for anatomies stored in earlier sessions: you do not need to segment again.

Note: This action requires the engineering module, the module that then uses the project. Without it, none of the ways in below is shown.

Opening the Dialog

There are three ways in, and all of them open the same Create simulation project dialog:

• Viewer tool column: in the column of icons on the left edge of the viewer, below the lung and heart analysis icons, click the arrow icon (tooltip: Create a simulation project from the anatomies). It is active once a CT series is loaded; it is greyed out in comparative mode and when a project device is open.

• Data tree: hover the Anatomies category of the series and click its action icon. The dialog opens with all the anatomies of that category already selected.

• Segment & Reconstruct: after a segmentation, the Store selection as project section shows a Create simulation project button. The dialog opens with the segments you just produced already selected.

1. Anatomies to Send

The list shows every anatomy available for the series. Each entry carries a badge:

• Saved: the anatomy is already stored in the database
• In memory: a segment produced in this session and not yet saved as an anatomy

Tick one or more entries, or use Select all / Clear selection. When the series has more than six anatomies, a search field appears above the list to filter it. If you pick more than one, a hint confirms that they will be merged into one geometry: the project receives a single surface, not separate pieces.

2. Destination

• New project: type a name. A name you already use is rejected on the spot (A project with this name already exists), before any processing starts.
• Existing project: pick one of your projects. The geometry is added to it as a new device version.

Click Create project (or Add to project). The footer shows the progress — Preparing geometry…, Merging anatomies…, Creating project… — and the dialog cannot be closed until it finishes.

Result

When the project is ready, the dialog confirms it. Click Open project to continue in the engineering workspace, or Stay here to keep working on the patient.

Tip: You can also refine the surface in the CleanUp section before sending it — see the next tutorial.

Troubleshooting

Auto Segmentation Produces Nothing

• Verify the Target: make sure the chosen anatomy is actually present in the scan
• Check the acquisition: low-contrast or truncated scans reduce AI accuracy
• Lungs: enable Airways segmentation only when airways are in range

Region Growing Leaks

• Lower the threshold to tighten the intensity window
• Move the seed away from boundaries and vessels
• Press Backspace to clear the mask and retry

A Segment Is Not Visible in 3D

• Click the eye button next to the segment in Select segments

The Create Simulation Project Button Is Greyed Out or Missing

• Missing (from the viewer tool column, the data tree and Segment & Reconstruct alike): the account does not have the engineering module
• Greyed out (in the viewer tool column): load a CT series first, leave comparative mode, or close the project device you have open

”A Project with This Name Already Exists”

• Choose another name, or switch to Existing project to add the geometry to that project

Best Practices

1. Start with Auto segmentation and refine only when needed
2. Enable airways for lungs when virtual spirometry or surgery planning will follow
3. Merge related segments before storing so the anatomy is a single object
4. Name projects clearly in the Create simulation project dialog for easy retrieval