Inobitec DICOM Viewer

7.5. Vessel Analysis Mode

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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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After building the necessary centerlines, switch to the Vessel analysis mode by clicking on the Analysis mode PIC button. The window in the Vessel analysis mode is shown in Fig. 7.4.



The volume reconstruction is shown in the 3D View window, the curved surface is shown in the Curved surface window. The vessel sweep following the straightening of its centerline and the marking of its borders is shown in the Straightened vessel window. The sections by the planes that are perpendicular to the centerline are shown in the Section window.

You cannot edit the centerline in the Vessel analysis mode. To do it swith to Centerline building mode by clicking the Analysis mode PIC button.

7.5.1 Vessel borders

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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 DICOM Viewer calculates the inner and outer borders of a vessel and the border of calcifications inside a vessel (Fig. 7.5). If no calcifications are found, then the corresponding value remains empty. To see the tissues that correspond to the density ranges, click the Show vessel tissue PIC button. The tissues with an intensity between the inner border and the calcium border (vessel lumen) are highlighted in green, the tissues with an intensity between the outer and inner border (vessel wall) are highlighted in brown, and the tissues with an intensity higher than the calcium border (calcifications) are highlighted in white. The borders of the vessel are built in accordance with the threshold values, but due to certain smoothing they do not exactly correspond to the threshold values. In the Straightened vessel window, the green line indicates the inner border of the vessel, the red line indicates the outer border (fig. 7.6). The central line is shown as a straight line. To edit borders, activate the PIC Edit vessel contours tool, click the left mouse button at an arbitrary place near the border, the border will pass through the selected point. When you move the mouse while holding the left button, the border repeats the path of the cursor.

PIC You need to control the process of boundaries creation, as well as the threshold boundary and calcification values. If needed, change the boundaries and the threshold values manually.

To change the threshold values, enter new values in the appropriate fields and click the Apply button. The border will be rebuilt in accordance with the new values. To return to the threshold values calculated automatically, click the Restore button.

To undo the all changes and return to the initial borders, click on the arrow on the right side of the New Vessel PIC button and select the Rebuild edges command.

At the bottom of the Straightened Vessel window, there is a graph showing changes in the vessel lumen. The areas in which stenosis is possible are highlighted in red on the graph, the remaining sections are highlighted in green.





7.5.2 Section analysis

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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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To add a section, move the cursor to the centerline in the Curved surface, Straightened vessel or 3D View window, right-click and select the Add Section command or Add Reference to add a reference section.

To delete a section, select the Remove section command in the context menu of the section or click on the cross in the upper right-hand corner of the current section window (Fig. 7.7).

The position of the cross on the section corresponds to the position of the centerline.

The borders are outlined by the green and red lines. When editing borders in the current section window (Fig. 7.7), the PIC Edit vessel contours tool can be deactivated.

The yellow line in the current section window shows the cutting plane for the current section shown in the Straightened vessel window. To rotate the cutting plane, move the cursor over it so that a bidirectional arrow appears, hold the left mouse button and move the mouse.

The following parameters are calculated in the section view windows:

  • Lumen
  • Short diameter
  • Long diameter

If you set one section as a reference, then the diameter and lumen values for the other sections are relative to the corresponding values for the reference section. If you set two sections as a reference, then the values for the other sections are relative to the average values for the reference sections. It is recommended to locate the reference sections on both sides of the section of interest if the vessel narrows. To set the type of the section, select it from the drop-down list in the upper left-hand corner of the section view window (Fig. 7.7).



7.5.3 Curved surface analysis

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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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A vessel sweep is diaplayed in the Curved surface and Straightened vessel windows.

The Straightened vessel window displays the following information:

  1. Thiskness
  2. Curve rotation angle

To analyze the vessel interval, select this interval in the Straightened vessel window. To do this, move the cursor to the beginning of the interval and move the mouse to the end of the interval, holding down the left mouse button, then release the button. The built interval is shown in Fig. 7.8. The borders of the interval are diplayed as white sections.



The following parameters are calculated for the interval:

  • Length;
  • Avg lumen;
  • Min lumen.

To move the interval border, move the cursor to the corresponding white section in any of the 3D View, Curved surface or Straightened vessel windows and move it with the mouse while holding down the left button. To delete an interval, click the left mouse button at an arbitrary place in the Straightened vessel window. To build multiple intervals, build them holding down the Ctrl button on the keyboard.

7.5.4 Export vessel surface mesh

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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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To export the vessel surface to a file, click on the Export vessel surface mesh PIC button, in the dialog that opens, select the file type (ply, obj or stl) and save the mesh.

To close the ends of the vessel, click on the arrow on the right side of the Export vessel surface mesh PIC button, select the Export parameters... item and in the dialog that opens, check the Close sides box.