Difference between revisions of "CT urography"

From radlines.org
Jump to navigation Jump to search
m (→‎Evaluation: Formatting)
(→‎Evaluation: Linked)
 
(6 intermediate revisions by the same user not shown)
Line 7: Line 7:
 
==Configuration==
 
==Configuration==
 
In Swedish practice,<ref>{{NU Hospital Group}}, 2018</ref> the protocol is determined by age:
 
In Swedish practice,<ref>{{NU Hospital Group}}, 2018</ref> the protocol is determined by age:
−
*In patients under 40 years:
+
*In patients under 40 years, generally:
 
:#Low-radiation-dose of urinary system, without IV contrast
 
:#Low-radiation-dose of urinary system, without IV contrast
 
:#Normal-radiation-dose with split bolus IV contrast, 7.5 minutes and 90 seconds before image acquisition.
 
:#Normal-radiation-dose with split bolus IV contrast, 7.5 minutes and 90 seconds before image acquisition.
−
*In patients over 40 years:
+
*In patients over 40 years, or younger if suspicion of cancer is high:
 
:#Low-radiation-dose of whole abdomen, without IV contrast
 
:#Low-radiation-dose of whole abdomen, without IV contrast
 
:#Normal-radiation-dose of whole abdomen 20 seconds after [[bolus tracking]], for visualization of renal cortex.
 
:#Normal-radiation-dose of whole abdomen 20 seconds after [[bolus tracking]], for visualization of renal cortex.
Line 17: Line 17:
  
 
Regardless of age, 1 liter water is given orally 1 hours before the CT, as well as avoiding urination during 1 hour before, in order to increase renal filtration and distend the bladder.<ref name="RamanFishman2014"/> If the images show insufficient contrast filling in the renal pelvices and ureters, an additional image is taken after 5 minutes, possibly with the patient lying on the stomach to make gravity help fill the ureters.
 
Regardless of age, 1 liter water is given orally 1 hours before the CT, as well as avoiding urination during 1 hour before, in order to increase renal filtration and distend the bladder.<ref name="RamanFishman2014"/> If the images show insufficient contrast filling in the renal pelvices and ureters, an additional image is taken after 5 minutes, possibly with the patient lying on the stomach to make gravity help fill the ureters.
 +
 +
If patient has flank pain, a '''[[CT of kidney stone disease]]''' (without IV contrast) should be done instead.
  
 
==Evaluation==
 
==Evaluation==
−
*CT without contrast: As '''[[CT of kidney stone disease]]'''.
+
*CT without contrast: Look for:
 +
<gallery>
 +
File:3mmstone.png|Ureteral stones. <br>If found, see '''[[CT of kidney stone disease]]'''.
 +
</gallery>
 
*CTs with contrast: Tumors within the kidney, ureters or bladder.
 
*CTs with contrast: Tumors within the kidney, ureters or bladder.
 +
[[File:CT of bladder cancer.jpg|thumb|200px|Nodular bladder tumor.]]
 +
:*If suspected solid renal mass, see: '''[[CT of renal tumors]]'''
 
:*Signs of bladder tumor:
 
:*Signs of bladder tumor:
−
::*Bladder wall thickening, especially when nodular or irregular.<ref name="RamanFishman2014"/> However, the anterior wall is frequently thickened in a normal underdistended bladder.<ref name="RamanFishman2014"/> Also, diffuse bladder wall thickening rarely represents malignancy.<ref name="RamanFishman2014"/> Look both at images 40 seconds after IV contrast and with contrast-containing bladder lumen, since that contrast may both demarcate a tumor as well as obscure one by beam-hardening artifacts.<ref name="RamanFishman2014"/>
+
::*Bladder wall thickening, which may indicate a bladder tumor, especially when nodular or irregular.<ref name="RamanFishman2014"/> Look both at images 40 seconds after IV contrast and with contrast-containing bladder lumen, since that contrast may both demarcate a tumor as well as obscure one by beam-hardening artifacts.<ref name="RamanFishman2014"/> In suspected bladder tumor, see '''[[CT of urinary bladder tumors]]'''
 
:*Lymph nodes. Enlarged lymph nodes may be metastases. Generalized lymphadenopathy may indicate lymphoma, and in such cases tumors in the urinary system may be lymphomas as well.<ref name="RamanFishman2014"/>
 
:*Lymph nodes. Enlarged lymph nodes may be metastases. Generalized lymphadenopathy may indicate lymphoma, and in such cases tumors in the urinary system may be lymphomas as well.<ref name="RamanFishman2014"/>
−
 
−
===Further evaluation of suspected tumors===
 
−
[[File:CT of bladder cancer.jpg|thumb|Nodular bladder tumor.]]
 
−
*Evaluate '''contrast enhancement''' by comparing images before and after IV contrast. Any focal hyperenhancement of the bladder wall must be considered suspicious for malignancy.<ref name="RamanFishman2014"/> For transitional cell cancers, the most common form of bladder cancer, enhancement peaks at about 100 HU at approximately 60 seconds, and then decreasing slowly.<ref name="RamanFishman2014"/> In lack of enhancement, consider a differential diagnosis of a hematoma, although the presence of an underlying tumor is still difficult to exclude.<ref name="RamanFishman2014"/>
 
−
*Measure '''size'''
 
−
*For bladder tumors:
 
−
:*Classify '''shape''' such as for example nodular or polypoid. In case of well circumscribed and smoothly marginated borders, consider bladder leiomyoma as a differential diagnosis.<ref name="RamanFishman2014"/>
 
−
:*Note any '''calcification''' of the bladder wall, indicates cystoscopy, particularly when there is bladder wall thickening.<ref name="RamanFishman2014"/>
 
−
:*Signs of local spread or '''metastasis'''. The most commons sites of metastasis of bladder cancers are lymph nodes, bones, lungs, liver and peritoneum.<ref name="ShinagareRamaiya2011">{{cite journal|last1=Shinagare|first1=Atul B.|last2=Ramaiya|first2=Nikhil H.|last3=Jagannathan|first3=Jyothi P.|last4=Fennessy|first4=Fiona M.|last5=Taplin|first5=Mary-Ellen|last6=Van den Abbeele|first6=Annick D.|title=Metastatic Pattern of Bladder Cancer: Correlation With the Characteristics of the Primary Tumor|journal=American Journal of Roentgenology|volume=196|issue=1|year=2011|pages=117–122|issn=0361-803X|doi=10.2214/AJR.10.5036}}</ref>
 
−
 
 
{{Bottom}}
 
{{Bottom}}

Latest revision as of 11:33, 2 August 2019

Author: Mikael Häggström [notes 1]

Planning

Indication for CT urography in hematuria

Most patients with macroscopic hematuria, especially when over 50 years, should undergo both cystoscopy and CT urography.[1]

Microscopic hematuria indicates further workup with cystoscopy and/or CT urography if there are significant underlying risk factors, mainly:[1]

  • Male sex
  • Age, especially being older than 60 years
  • Smoking
  • Pelvic radiation

Configuration

In Swedish practice,[2] the protocol is determined by age:

  • In patients under 40 years, generally:
  1. Low-radiation-dose of urinary system, without IV contrast
  2. Normal-radiation-dose with split bolus IV contrast, 7.5 minutes and 90 seconds before image acquisition.
  • In patients over 40 years, or younger if suspicion of cancer is high:
  1. Low-radiation-dose of whole abdomen, without IV contrast
  2. Normal-radiation-dose of whole abdomen 20 seconds after bolus tracking, for visualization of renal cortex.
  3. Normal-radiation-dose of upper abdomen 40 seconds after the previous, for visualization of all renal parenchyma.
  4. Normal-radiation-dose of urinary system 7.5 minutes after IV contrast, for renal pelvises and ureters.

Regardless of age, 1 liter water is given orally 1 hours before the CT, as well as avoiding urination during 1 hour before, in order to increase renal filtration and distend the bladder.[1] If the images show insufficient contrast filling in the renal pelvices and ureters, an additional image is taken after 5 minutes, possibly with the patient lying on the stomach to make gravity help fill the ureters.

If patient has flank pain, a CT of kidney stone disease (without IV contrast) should be done instead.

Evaluation

  • CT without contrast: Look for:
  • CTs with contrast: Tumors within the kidney, ureters or bladder.
Nodular bladder tumor.
  • Bladder wall thickening, which may indicate a bladder tumor, especially when nodular or irregular.[1] Look both at images 40 seconds after IV contrast and with contrast-containing bladder lumen, since that contrast may both demarcate a tumor as well as obscure one by beam-hardening artifacts.[1] In suspected bladder tumor, see CT of urinary bladder tumors
  • Lymph nodes. Enlarged lymph nodes may be metastases. Generalized lymphadenopathy may indicate lymphoma, and in such cases tumors in the urinary system may be lymphomas as well.[1]

Notes

  1. ↑ For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Radlines:Authorship for details.

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 USA: Raman, Siva P.; Fishman, Elliot K. (2014). "Bladder Malignancies on CT: The Underrated Role of CT in Diagnosis ". American Journal of Roentgenology 203 (2): 347–354. doi:10.2214/AJR.13.12021. ISSN 0361-803X. 
  2. ↑ NU Hospital Group, Sweden, 2018
Retrieved from "https://radlines.org/index.php?title=CT_urography&oldid=3848"