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RadiAnt DICOM Viewer - Discussion Forum

Sep 27, 2012 03:37 PM
by george
i use radiant dicom viewer for re-examine cardiac ultrasound studies.
I am a new user...
When i click to measure i.e. a distance, the result is in px (what does it mean?). How can i measure in cm instead?

thank you
Sep 27, 2012 04:47 PM
by RadiAnt
Dear George,

When you open the DICOM file without pixel spacing data (which is the case with your ultrasound study) you will only get measurements in pixels.
Currently there is no way to manually calibrate such image.

The workaround:
1) measure the ruler included in your US image
2) divide the ruler length (in centimeters) by the value of measurement (in pixels)
3) measure your object of interest and multiply the value in pixels by the ratio you got in the second step

Sep 28, 2012 07:33 AM
by Guest
ok, thanks Maciej.

it seems it works ok

Jul 7, 2014 12:04 PM
by Diogo Moutinho
I'm using Radiant (CD\DVD VERSION
Some images, from some manufacturers, use a different tag for pixel spacing. This version uses: 0028,0030 pixel spacing.
We have a client that is trying to measure images that are using a different tag for pixel spacing.(0018,1164) ImagerPixelSpacing.

Is there support for this? On this version?

Jul 7, 2014 06:36 PM
by RadiAnt
Dear Diogo,

Support for measurements with imager pixel spacing attribute was introduced in version
You can check the complete version history here:
And here is the manual page about length measurements:

Kind regards,
Jul 24, 2014 05:48 PM
by Rami
I am trying to measure surface area of an irregular object on MRI images, is this possible. The ellipse tool is not appropriate and the pencil tool doesn't give area.

Aug 12, 2014 07:12 AM
by Luke

I'd like to add special annotation and measurement tools, for example, for chiropractic imaging. Is it possible to develop and add plugins to the RadiAAnt image viewer?
Aug 13, 2014 08:49 AM
by RadiAnt

Currently only measurements from the ellipse area are possible.


I'm afraid that the plugin architecture in RadiAnt won't be available anytime soon...
Sep 19, 2015 06:15 PM
by Gustavo
There is possible to measure area in Dicom Viewer?
Sep 19, 2015 06:23 PM
by Gustavo
Sorry, the answer is above...
There is another software that do this?
Sep 21, 2015 06:18 PM
by Guest
You could use Osirix, but it's for Mac computers only...
Sep 30, 2015 05:20 AM
by umesh
there is a ellipse tool what does it measure acctually as i found more value on opaque part and less value on lucent part
Sep 30, 2015 02:40 PM
by RadiAnt
It depends on the modality of the image that you measure. For CT this would be Hounsfield units. For CR this could be the optical density. PET images usually have Becquerels/milliliter or counts.
Oct 1, 2015 03:34 AM
by umesh
what about the dx is it possible to measure bone density in hounsfield unit for DX file with ellipse tool
Oct 2, 2015 10:08 AM
by RadiAnt
I don't think so. Hounsfield units are specific for the CT modality.
Aug 14, 2018 08:53 PM
by sam

i was just wondering how to find out the vauxhall size/ how much each pixel is in each image
Aug 21, 2018 08:31 PM
by RadiAnt
To find out the size of the pixel in your image, press Ctrl+Alt+T to show the DICOM tags window and find the pixel spacing element. It shows the dimensions of a pixel in milimeters, e.g.:

(0028,0030) DS 0.388672\0.388672 # 2, 18 Pixel Spacing
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