Contrast Accumulation Curve

Creating a Contrast Accumulation Curve

• Display on screen the series necessary for creating the Contrast Accumulation curve (minimum two: non-contrast and contrast-enhanced)
• Create any figure or region of interest (ROI) in the area of interest
• Click the "More" icon in the upper right corner of the measurement result
• Click on the "Create Accumulation Curve" item in the menu that appears

Copies of the created region will appear on all series, and the Contrast Accumulation curve graph window will open

Accumulation Curve Management:

• Clicking on the curve number selects the curve
• Clicking the More button next to the curve number brings up a menu to rename the curve, change its color, or delete it
• In the lower part of the window, you can select the parameter for data display
• The "Analysis" button allows you to calculate contrast washout or half-life time
• The "Save" button saves the Contrast Accumulation curve to a user series
• The "Close" button closes the curve window without saving

For comparative analysis of different regions, create a new ROI and repeat the steps
Curves are distinguished by color and correspond to their region by number

Correcting Region of Interest Position Due to Patient Motion or Respiration

Analyze the position of the regions in the series
When creating a Contrast Accumulation curve, a group of identical, linked regions is created
Transforming or shifting one region leads to similar behavior in the others

• To correct the position of regions in the group, click on the "Open the Area" item in the "More" menu of the measurement result
  The region outline will be highlighted with a white dotted line
• Move the region within the image, or scroll through the images
• Repeat these operations on other regions if necessary
• Click on the "Close the Area" item on the last of the edited regions

Analyzing Contrast Washout

• Create a Contrast Accumulation curve
• In the Contrast Accumulation curve window, click the "Analyze" button, then on the "Contrast washout" item
• In the list that appears, select the non-contrast, venous (or portal), and delayed phases by clicking the checkboxes next to them, then click the "OK" button
• Notes:
  • The formula in this function is applicable only for adrenal glands
  • The delayed phase should be performed no earlier than 10 minutes
  Applied formulas:
  • Absolute washout - [( HU venous (portal) phase ) - ( HU delayed ))] / [( HU venous (portal) phase ) - ( HU non-contrast phase )] x 100
  • Relative washout - [( HU venous (portal) phase ) - ( HU delayed )] / ( HU venous (portal) phase ) x 100
• A window with the calculation results will appear
  Click the button to copy to the clipboard, for subsequent pasting into any document
  Click the button to save to a user series
  Click the "Close" button to close this window