Anorectal Disease

Variant: 1 Suspected perianal disease. Abscess or fistula. Initial imaging.

Procedure	Appropriateness Category	Relative Radiation Level
MRI pelvis without and with IV contrast	Usually Appropriate	O
CT pelvis with IV contrast	Usually Appropriate	☢☢☢
US endoanal	May Be Appropriate	O
MRI pelvis without IV contrast	May Be Appropriate	O
CT pelvis without IV contrast	May Be Appropriate	☢☢☢
Radiography pelvis	Usually Not Appropriate	☢☢
Fluoroscopy contrast enema	Usually Not Appropriate	☢☢☢
Fluoroscopy fistulography anus	Usually Not Appropriate	☢☢☢
CT pelvis without and with IV contrast	Usually Not Appropriate	☢☢☢☢

Variant: 2 Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.

Procedure	Appropriateness Category	Relative Radiation Level
MRI pelvis without and with IV contrast	Usually Appropriate	O
CT pelvis with IV contrast	Usually Appropriate	☢☢☢
US pelvis transrectal	May Be Appropriate	O
Fluoroscopy contrast enema	May Be Appropriate	☢☢☢
Fluoroscopy cystography	May Be Appropriate	☢☢☢
Fluoroscopy vaginography	May Be Appropriate	☢☢☢
MRI pelvis without IV contrast	May Be Appropriate	O
Radiography pelvis	Usually Not Appropriate	☢☢
CT pelvis without IV contrast	Usually Not Appropriate	☢☢☢
CT pelvis without and with IV contrast	Usually Not Appropriate	☢☢☢☢

Variant: 3 Suspected proctitis or pouchitis. Initial imaging.

Procedure	Appropriateness Category	Relative Radiation Level
MR enterography	Usually Appropriate	O
MRI pelvis without and with IV contrast	Usually Appropriate	O
CT pelvis with IV contrast	Usually Appropriate	☢☢☢
CT enterography	Usually Appropriate	☢☢☢☢
Fluoroscopy contrast enema	May Be Appropriate	☢☢☢
MRI pelvis without IV contrast	May Be Appropriate	O
US pelvis	Usually Not Appropriate	O
Radiography pelvis	Usually Not Appropriate	☢☢
CT pelvis without IV contrast	Usually Not Appropriate	☢☢☢
CT pelvis without and with IV contrast	Usually Not Appropriate	☢☢☢☢
FDG-PET/CT skull base to mid-thigh	Usually Not Appropriate	☢☢☢☢
WBC scan abdomen and pelvis	Usually Not Appropriate	☢☢☢☢

Variant: 4 Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.

Procedure	Appropriateness Category	Relative Radiation Level
MRI pelvis without and with IV contrast	Usually Appropriate	O
CT abdomen and pelvis with IV contrast	Usually Appropriate	☢☢☢
CT pelvis with IV contrast	Usually Appropriate	☢☢☢
Fluoroscopy contrast enema	May Be Appropriate	☢☢☢
MRI pelvis without IV contrast	May Be Appropriate	O
CT abdomen and pelvis without IV contrast	May Be Appropriate	☢☢☢
CT pelvis without IV contrast	May Be Appropriate	☢☢☢
US pelvis transrectal	Usually Not Appropriate	O
Radiography abdomen and pelvis	Usually Not Appropriate	☢☢☢
CT abdomen and pelvis without and with IV contrast	Usually Not Appropriate	☢☢☢☢
CT pelvis without and with IV contrast	Usually Not Appropriate	☢☢☢☢

Panel Members

Summary of Literature Review

Introduction/Background

Special Imaging Considerations

Initial Imaging Definition

Discussion of Procedures by Variant

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
A. CT Pelvis

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
B. Fluoroscopy Contrast Enema

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
C. Fluoroscopy Fistulography

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
D. MRI Pelvis

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
E. Radiography Pelvis

Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging.
F. US Endoanal

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
A. CT Pelvis

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
B. Fluoroscopy Contrast Enema

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
C. Fluoroscopy Cystography

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
D. Fluoroscopy Vaginography

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
E. MRI Pelvis

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
F. Radiography Pelvis

Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging.
G. US Pelvis Transrectal

Variant 3: Suspected proctitis or pouchitis. Initial imaging.

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
A. CT Enterography

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
B. CT Pelvis

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
C. FDG-PET/CT Skull Base to Mid-Thigh

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
D. Fluoroscopy Contrast Enema

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
E. MR Enterography

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
F. MRI Pelvis

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
G. Radiography Pelvis

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
H. US Pelvis

Variant 3: Suspected proctitis or pouchitis. Initial imaging.
I. WBC Scan Abdomen and Pelvis

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
A. CT Abdomen and Pelvis

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
B. CT Pelvis

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
C. Fluoroscopy Contrast Enema

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
D. MRI Pelvis

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
E. Radiography Abdomen and Pelvis

Variant 4: Suspected complication postproctectomy or coloproctectomy or colectomy with pouch or other anastomosis. Initial imaging.
F. US Pelvis Transrectal

Summary of Recommendations

Supporting Documents

The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.

For additional information on the Appropriateness Criteria methodology and other supporting documents, please go to the ACR website at https://www.acr.org/Clinical-Resources/Clinical-Tools-and-Reference/Appropriateness-Criteria.

Appropriateness Category Names and Definitions

Appropriateness Category Name	Appropriateness Rating	Appropriateness Category Definition
Usually Appropriate	7, 8, or 9	The imaging procedure or treatment is indicated in the specified clinical scenarios at a favorable risk-benefit ratio for patients.
May Be Appropriate	4, 5, or 6	The imaging procedure or treatment may be indicated in the specified clinical scenarios as an alternative to imaging procedures or treatments with a more favorable risk-benefit ratio, or the risk-benefit ratio for patients is equivocal.
May Be Appropriate (Disagreement)	5	The individual ratings are too dispersed from the panel median. The different label provides transparency regarding the panel’s recommendation. “May be appropriate” is the rating category and a rating of 5 is assigned.
Usually Not Appropriate	1, 2, or 3	The imaging procedure or treatment is unlikely to be indicated in the specified clinical scenarios, or the risk-benefit ratio for patients is likely to be unfavorable.

Relative Radiation Level Information

References

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Disclaimer

The ACR Committee on Appropriateness Criteria and its expert panels have developed criteria for determining appropriate imaging examinations for diagnosis and treatment of specified medical condition(s). These criteria are intended to guide radiologists, radiation oncologists and referring physicians in making decisions regarding radiologic imaging and treatment. Generally, the complexity and severity of a patient’s clinical condition should dictate the selection of appropriate imaging procedures or treatments. Only those examinations generally used for evaluation of the patient’s condition are ranked. Other imaging studies necessary to evaluate other co-existent diseases or other medical consequences of this condition are not considered in this document. The availability of equipment or personnel may influence the selection of appropriate imaging procedures or treatments. Imaging techniques classified as investigational by the FDA have not been considered in developing these criteria; however, study of new equipment and applications should be encouraged. The ultimate decision regarding the appropriateness of any specific radiologic examination or treatment must be made by the referring physician and radiologist in light of all the circumstances presented in an individual examination