Visceral Adipose Tissue Program

Foreword

This program is based on the method for determining abnormalities in the accumulation and distribution of abdominal visceral adipose tissue using computed tomography, proposed by L. Sjostrom in 1986
The method is based on measuring the areas of subcutaneous adipose tissue and visceral adipose tissue

Launching the "Visceral Adipose Tissue" Program

In standard MPR, select an axial scan at the L4-L5 level

Click in the toolbar, in the "Studies" group, on the "Programs" button
Click on the "Visceral Adipose Tissue" button
The screen will split into 2 panels:
- Axial scan
- Control panel
The program will automatically highlight adipose tissue on the axial scan

Control Panel

Elements from top to bottom:

Results calculation table
- SAT (Superficial adipose tissue) - Superficial fat
  The value is only accurate after subtracting visceral fat
- SSAT (Superficial Subcutaneous Adipose Tissue) - Superficial subcutaneous fat
  The value is only accurate after subtracting deep subcutaneous fat
- DSAT (Deep Subcutaneous Adipose Tissue) - Deep subcutaneous fat
  Outlined manually
- VAT (Visceral Adipose Tissue) - Visceral fat. Outlined manually
Sliders for setting the adipose tissue range
To the right of them are buttons to return to default values
Slider for the opacity of the adipose tissue mask coloring
Toggle button to show/hide the adipose tissue mask
Buttons for contours of visceral fat and superficial fascia

Manual Annotation Tool

For outlining, a tool similar to a closed curve is used

Sequence of Actions

Verifying Automatic Adipose Tissue Detection

Click in the program's control panel on the button (clicking again shows the coloring), or move the "Opacity" slider to the left to view the adipose tissue on the reference scan
By moving the sliders for adipose tissue thresholds, achieve optimal display (coloring) of the adipose tissue

Creating Regions of Interest

Click the "Visceral Fat" button
With clicks, outline the visceral fat area on the axial scan
Click the "Show/hide adipose tissue coloring" button
Click the "Superficial Fascia" button
With clicks, outline the superficial fascia on the axial scan
Click again on the "Show/hide adipose tissue coloring" button

Note:

Minor inaccuracies (such as including a vertebra or psoas muscle) when outlining the visceral fat area are acceptable, as the program will not take into account densities outside the acceptable range
Sufficient accuracy is required when outlining the superficial fascia

Saving Results

After outlining the two areas, the results will appear in the table

Saving within Vidar Dicom Viewer

The program saves automatically upon exit
To display on screen, click on the "Visceral Adipose Tissue" item in the Finds list in the Preview Bar

Saving the Result in the Study Protocol

Click the "Copy" button

to copy the analysis results to the clipboard for subsequent pasting into a standard text document

Saving the Table with Data

Click the "Print" button to send the table for printing
Click the "Save User Series" button to save the table to a user series (it will be located in the Preview Bar at the end of the study)
To save images, use the "Image - to file" and "Screen - to file" buttons in the toolbar

Exiting the "Visceral Adipose Tissue" Program

Click the "Visceral Adipose Tissue" button in the program header
Click on the "Exit mode" item

The screen split will return to the standard one