To measure an area that does not fit neatly into a rectangular or elliptical shape, use the Markup Freeform tool to create a custom polygon.
To measure a freeform area
From the Image area top toolbar, Markup button menu, select Markup Freeform.
Click one corner of the region to measure.
Move the pointer to another corner and click.
Repeat step 3 until the polygon is fully defined.
To set the polygon, right-click.
Region measurements such as Perimeter, Area, and Average are displayed outside the polygon. Which values appear is based on user profile settings.
If necessary, move or resize the freeform markup:
To move the polygon, drag the center control point to a new position.
To resize the polygon, drag one of the outer control points to a new position.
To move the measurement text, drag the measurement text control point to a new position.
To set the measurement, right-click.
The measurement values and units used depend on the calibration applied or available to the study. Refer to Understanding measurement values and units used.
To delete the polygon, press the Delete key.
 | Note: When values are approximate, a ~ character appears. If part of the markup is off the image, an asterisk (*) appears after the Average and Standard Deviation measurements (if displayed). The off-image pixels are not included in the Average and Standard Deviation calculations but are still included in the Pixel, Perimeter, and Area values. If the markup is completely off the image, the Average and the Standard Deviation are not displayed. |