Navigation:  Image Viewer > Advanced Viewing >

Standardized Uptake Value (SUV)

Previous pageReturn to chapter overviewNext page


This is a premium feature and may not be available in all installations.


Standardized uptake value (SUV) is a tool commonly used in PET image analysis. It measures the concentration of a radiotracer in a defined region of interest (ROI). The value is calculated based on the information stored in the DICOM image.

Important Note

SUV calculation in ClearCanvas Workstation is based on generally accepted methods and equations. However, some institutions may use methods and/or equations that differ from those stated in this user's guide. Prior to use in a clinical setting, it is important that all equations be confirmed and an independent evaluation be conducted of the SUV values reported by ClearCanvas Workstation with studies from all the PET acquisition devices at your facility, under typical acquisition conditions. See the Safety Instructions for more details.

SUV Region Measurements

SUV is calculated for 2D ROI measurements (elliptical, rectangular and polygonal ROIs) when they are drawn on a PET or PET-CT fusion image. The following information is displayed in the callout:

The SUV calculation method: body weight (bw), lean body mass (lbm) or body surface area (bsa); this can be changed in the configuration
The SUV units used
The mean and maximum SUV in the region


SUV is calculated entirely based on the information stored in the image header. It is the technician's responsibility to ensure all necessary information is entered correctly. See this for the list of tags that are required.
The images must be decay-corrected.
If SUV cannot be computed due to missing or invalid data, check the log for the exact problem.
Many factors can affect the accuracy of SUV measurements, including image noise/background activity, attenuation correction and patient motion artifacts, partial volume effects, patient size, the timing of the scan post-injection, as well as user-bias when drawing the ROI.


SUV on PET/CT Fusion Images

Since PET/CT fusion images are constructed from a volume generated from the PET images, SUV computation is subject to the interpolation algorithm used in the software. In addition, information used for computing SUV must be consistent across all PET images. As such, it is possible that SUV can be computed on a single PET image but not on the fusion image. It is also common that SUV reported on fusion images are slightly different from those on the PET images. If there is ever any doubt about the SUV value reported on a fusion image, you can always draw the same ROI on the closest image in the source PET series.

Calculation Details

SUV Formulas





Activity Concentration



Injected Dose



Dose Decay Correction Factor



Body Weight



Lean Body Mass



Body Surface Area



Required Data

The following DICOM tags are used to calculate SUV via the various methods:



Expected Value

Used For


Patient's Sex

M or F



Patient's Size

Patient's height in metres

SUVlbm , SUVbsa


Patient's Weight

Patient's weight in kg

SUVbw , SUVlbm , SUVbsa


Series Date

Decay correction


Series Time

Decay correction


Radiopharmaceutical Start DateTime

Radiopharmaceutical administration time

Decay correction


Radiopharmaceutical Start Time

Radiopharmaceutical administration time

Decay correction


Radionuclide Total Dose

Radiopharmaceutical dose administered to patient at administration time in becquerels (Bq)

Injected Dose


Radionuclide Half Life

Radionuclide half life in seconds

Decay correction



Pixel value units (after conversion)



Rescale Slope, Rescale Intercept

Non-zero slope

Converts pixel values to Bq/ml (Activity Concentration)

Additionally, the following manufacturer-specific tags are used in the calculation.




Expected Value

Used For



Philips' private tag for SUV Scale Factor


Only used for Philips images to calculate SUV directly from pixel values



Philips' private tag for Activity Concentration Scale Factor


Only used for Philips images to convert pixel values to Bq/ml (Activity Concentration)



GE's private tag for scan time


Decay correction (for post-processed series only)


Lean Body Mass

Lean body mass is calculated using the James formula for females and the Morgan formula for males:





W = Patient's Weight in kg        H = Patient's Height in cm


Body Surface Area

Body surface area is calculated using the Du Bois formula:


W = Patient's Weight in kg        H = Patient's Height in cm


Decay Correction

The injected dose used to calculate SUV is corrected for the decay that occurs between the time of injection and the start of the scan using the formula:

T1/2 = Radionuclide half life in seconds

If Decay Correction = START, = Series Time - Radiopharmaceutical Start Time (for GE post-processed series, series time is retrieved from the private tag)

If Decay Correction = ADMIN, = 0


ClearCanvas Workstation will not calculate SUV on images that have not been decay-corrected by the acquisition device.



[1]James, W. Philip T. Research on obesity. London: Her Majesty's Stationery Office, 1976. ISBN 0114500347.
[2]Morgan, Denis J. and Bray, Kelly M. Lean Body Mass as a Predictor of Drug Dosage: Implications for Drug Therapy. Clinical Pharmacokinetics. 1994, Vol. 26, 4, pp. 292-307.
[3]Du Bois, Delafield and Du Bois, Eugene F. A formula to estimate the approximate surface area if height and weight be known. Archives of Internal Medicine. 1916, Vol. 17, 6-2, pp. 863-871.


ClearCanvas Workstation, Personal - User's Guide
© 2005-2015 Synaptive Medical