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Mainly bladder cancer
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|author1=[[User:Mikael Häggström|Mikael Häggström]]
|author2=
}}
==Planning==
{{Hematuria - indication of CT urography}}
==Configuration==
In Swedish practice,<ref>{{NU Hospital Group}}, 2018</ref> the protocol is determined by age:
*In patients under 40 years:
:#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.
*In patients over 40 years:
:#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 upper abdomen 40 seconds after the previous, for visualization of all renal parenchyma.
:#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.<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.
==Evaluation==
*CT without contrast: As '''[[CT of kidney stone disease]]'''.
*CTs with contrast: Tumors within the kidney, ureters or bladder.
:*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"/>
::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===
[[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}}
|author1=[[User:Mikael Häggström|Mikael Häggström]]
|author2=
}}
==Planning==
{{Hematuria - indication of CT urography}}
==Configuration==
In Swedish practice,<ref>{{NU Hospital Group}}, 2018</ref> the protocol is determined by age:
*In patients under 40 years:
:#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.
*In patients over 40 years:
:#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 upper abdomen 40 seconds after the previous, for visualization of all renal parenchyma.
:#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.<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.
==Evaluation==
*CT without contrast: As '''[[CT of kidney stone disease]]'''.
*CTs with contrast: Tumors within the kidney, ureters or bladder.
:*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"/>
::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===
[[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>
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