3. Overview

3.1. The Main Toolbar

Figure 3.1: The main application toolbar.

The GTFlow application is structured over several functional pages, which can be selected on the main toolbar at the top of the application. The toolbar also provides access to the program settings and to the quick-access menu.

3.2. The Start Page

Figure 3.2: The Start Page.

When launching the GTFlow application, the Start Page is displayed. Here data files and session files can be opened from disk. Also lists of recently used files and sessions are displayed for quick access. The start page also provides links to the documentation, to the built-in demo dataset, and to the synthetic data generator. Finally, version and license information is displayed in the lower right box.

3.3. The Organize Page

Figure 3.3: The Organize Page.

The Organize Page provides the functionality to load and pre-process datasets, as well as to aggregate them into a flow dataset. The flow dataset consists of a magnitude and 3 velocity encoded phase datasets along with the velocity encoding factors that define the velocity field. When loading files, GTFlow will attempt to populate the flow dataset automatically. The configuration however can also be set manually. The controls on the right of the organize page allow to mask the velocity field of the current flow dataset using any combination of implicit or explicit voxel masks. In addition, the velocty field can be corrected for phase offsets typically resulting from eddy currents during acquisition. Phase aliasing due to inadequate velocity encoding strengths can also be corrected for.

The Time Control Bar at the bottom of the page allows to scroll through the individual heart phases of the currently displayed dataset. A time animation mode allows to continuously loop through the heart phases.

3.4. The Analyze Page

Figure 3.4: The Analyze Page.

The Analyze Page has two or three side-by-side windows which can be individually configured to display any of the components of the flow dataset in any available native or resliced orientation. Various color overlays can also be configured.

The controls on the left of the page allow to generate an arbitrary number of image reslice stacks from the current flow dataset. The main purpose of reslice stacks is to obtain an image plane perpendicular to the blood vessel of interest. Once such a view is available, the vessel can be manually segmented by contouring the lumen of the vessel with a contour. A contour has a representation in each heart phase and can be adapted to a vessel lumen or position change over time. However, drawing a contour in each heart phase is optional. In any heart phase with no contour representation, the contour closest in time will be used.

Contours defined on the analyze page will also be visible on the visualize page. Velocity and flow statistics of each contour will be listed on the statistics page.

3.5. The Segment Page

coming soon.

3.6. The Visualize Page

coming soon.

3.7. The Statistics Page

coming soon.

3.8. Mouse and Keyboard Controls

Image display can be controlled in each viewer window individually. Move the mouse cursor inside a viewer window and use the following mouse and keyboard controls:

3.8.1. 2D Viewer

Function	Control
Context Menu	right mouse button
Zoom	middle+left mouse buttons or mousewheel
Reset zoom	context menu -> Fit to window
Pan	middle+right mouse buttons
Contrast	middle mouse button
Reset contrast	context menu -> Reset window/level
Select voxel	<Shift> + left mouse button

3.8.2. Contour Editing (Analyze Page)

Function	Control
Draw contour	left mouse button (A contour must be selected in the contour list)
Close contour	double-click left mouse button (in B-Splines and Polygone darwing modes)
Select contour	<Ctrl> + left mouse button inside contour, or double-click in contour list
Deselect contour	<Ctrl> + left mouse button outside contour
Edit selected contour	left mouse button
Delete contour vertex	middle mouse button on vertex (in B-Splines and Polygone darwing modes)
Delete selected contour	delete button in countour list command bar
Copy selected contour	copy buttons in countour list command bar
Move selected contour	<Alt> + left mouse button
Move all contours	<Alt-Shift> + left mouse button
Draw iso contours	<Shift> + left mouse button (in Freehand, B-Splines and Polygone drawing modes)
Undo contour editing	undo button in countour list command bar
Redo contour editing	redo button in countour list command bar

3.8.3. 3D Scene Viewer (Segment + Visualize Pages)

Function	Control
Context Menu	right mouse button
Zoom	middle+left mouse buttons or mousewheel
Reset zoom	context menu -> Fit to window
Pan	middle+right mouse buttons
Rotate	<CTRL-Shift> + left mouse button