# Computed Tomography - CT

<mark style="color:$danger;">**This Editorial Guide is used for Education Purposes Only. It is used in the Authoring Courses and Certifications. It is based on the January 2026 Editorial Guide.**</mark>

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**Exception for abbreviation**

CT is an exception to the rule that all abbreviations should have their expanded form in parentheses in descriptions.
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**Axial & Scan**

*Legacy issues: Existing computerized tomography concepts will be renamed consistently when the Quality Initiative undertakes improvement of the procedure hierarchy.*

**Axial**

Requests for new descriptions with \_computerized axial tomography (\_*CAT)* are not acceptable. The *axial* part of the phrase is no longer accurate, because there are other techniques that also create images on multiple planes or axes.

**Scan**

Computed tomography descriptions do not routinely include computed tomography *scan of X.*

The word *scan* is not systematically added in new descriptions and should not be included in preferred terms. However, specific requests to add descriptions with the word *scan* are not denied.

*Computerized axial tomography scan* *of X* is considered obsolete and should not be added as a new description.
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## Computed tomography

* FSN: Computed tomography of X (procedure)
* PT: CT of X
* SYN: Computed tomography of X
* For example,
  * 241566009 | Computed tomography of elbow (procedure)|
    * FSN: Computed tomography of elbow (procedure)
    * PT: CT of elbow
    * SYN: Computed tomography of elbow

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**With Contrast**

CT angiography uses contrast in all cases of the procedure; this must be stipulated in the descriptions.
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## Computed tomography angiography with contrast

This naming pattern is used when an anatomical location is specified, but the blood vessel is not explicit.

* FSN: Computed tomography angiography of X with contrast (procedure)
* PT: CT angiography of X with contrast
* SYN: Computed tomography angiography of X with contrast
  * For example,
    * 582101000119108 |Computed tomography angiography of head with contrast (procedure)|
      * FSN: Computed tomography angiography of head with contrast (procedure)
      * PT: CT angiography of head with contrast
      * SYN: Computed tomography angiography of head with contrast

## Computed tomography arteriography with contrast

* FSN: Computed tomography angiography of \[artery] with contrast (procedure)
* PT: CT angiography of \[artery] with contrast
* SYN: CT arteriography of \[body structure] with contrast
* SYN: Computed tomography arteriography of \[body structure] with contrast
* SYN: CT arteriogram of \[body structure] with contrast
  * For example,
    * 726077005 Computed tomography angiography of bronchial artery with contrast (procedure)
      * FSN: Computed tomography angiography of bronchial artery with contrast (procedure)
      * PT: CT angiography of bronchial artery with contrast
      * SYN: CT arteriography of bronchial artery with contrast
      * SYN: Computed tomography arteriography of bronchial artery with contrast

## Computed tomography venography with contrast

* FSN: Computed tomography venography of X with contrast (procedure)
* PT: CT venography of X with contrast
* SYN: CT venogram of X with contrast
* SYN: Computed tomography venography of X with contrast
  * For example,
    * 432842007 |Computed tomography venography of intracranial vein with contrast (procedure)|
      * FSN: Computed tomography venography of intracranial vein with contrast (procedure)
      * PT: CT venography of intracranial vein with contrast
      * SYN: Computed tomography venography of intracranial vein with contrast

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**Venography**

*Venography* may simply be a timing phase of *angiography*. It is agreed that venography may be a useful term in an FSN, i.e. there may be a meaningful technique difference between *simple angiography* and *purposeful venography*.
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## Computed tomography arthrography

* FSN: Computed tomography arthrography of X (procedure)
* PT: CT arthrography of X
* SYN: CT arthrogram of X
* SYN: Computed tomography arthrography of X
  * For example,
    * 418940000 | Computed tomography arthrography of intratarsal joint (procedure)|
      * FSN: Computed tomography arthrography of intratarsal joint (procedure)
      * PT: CT arthrogram of intratarsal joint
      * SYN: CT arthrography of intratarsal joint

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