Hi Michael,
I'm trying to figure out what kind of test I had a few years back.  I have my records and they say:
"CT of the abdomen and pelvis was performed with 5 mm collimations without intravenous or oral contrast. After the intravenous administration of 150 cc Isovue-300 by CT urography protocol, CT of the abdomen and pelvis was performed with 2.5 mm collimation. No oral contrast was administered."

My confusion lies in that my doctor ordered an abdominal CT w/wo contrast, but the tech said it was a CT urogram. I've read that CT urograms can have a lot of radiation so they don't do them to people under 40 (I was 27 at the time). Is that true?

I've also read that they involve three phrases, but this test seems to have only involved two. Is it possible to have a two phase urogram or did I just have an abdominal CT? Do you have any guess how many mSv's were involved in this test? I know that it can greatly differ based on machine, hospital, etc. But I was wondering if there was a median figure.

Thanks for you help, as usual.

Sounds like you have read a lot on the subject as the information you provide and the questions you raise are spot on!  

You are correct that CT urograms are usually not done on younger patients but not because they are young but rather because it is usually done for blood in the urine when we suspect cancer of the kidney, ureter, or bladder.  This diagnoses is usually suspected in older patients.  It may have a role in young people but uncommon. If young people have blood in urine it is most likely from a kidney stone. For that CT is usually done without any contrast.

Of course, CT urogram has more radiation since we scan three times.  The third phase is when we wrap around soft wide belt around you and squeeze it to help push the contrast from the kidneys into ureters so we can see them better and we scan the third time.  

I think what happened in your case is you got a CT abdomen and pelvis with and without contrast...but for some reason technique described mentioned urography protocol...hard to explain..I am not sure why it states that.  so in terms of radiation dose, you got 2 CTs.  You are absolutely correct that the dose depends on a lot of factors.  I would recommend you go to and plug in the test and your age etc.. it is a great site to get a median figure and more useful information.

Hope this is helpful.
Let me know if I can be of further assistance.


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Michael K.


Almost any kind of questions regarding any types of radiology exams, procedures, meaning of radiology reports etc...


12 year experience in the field of radiology

American Society of Neuroradiology, Senior Member Society of Pediatric Radiology, Active Member

Radiology Seminars in pediatric neurology American Journal of Roentgenology American Journal of Neuroradiology

Board Certified in Diagnostic Radiology Additional Certificate of Qualification in Neuroradiology

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