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Imaging After Liver Transplant

Variant: 1   Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US duplex Doppler abdomen Usually Appropriate O
CT abdomen with IV contrast Usually Appropriate ☢☢☢
CT abdomen with IV contrast multiphase Usually Appropriate ☢☢☢☢
US abdomen May Be Appropriate O
MRI abdomen without and with IV contrast with MRCP May Be Appropriate (Disagreement) O
CT abdomen without and with IV contrast May Be Appropriate ☢☢☢☢
Radiography abdomen Usually Not Appropriate ☢☢
MRI abdomen without and with IV contrast Usually Not Appropriate O
MRI abdomen without IV contrast Usually Not Appropriate O
MRI abdomen without IV contrast with MRCP Usually Not Appropriate O
CT abdomen without IV contrast Usually Not Appropriate ☢☢☢
CTA abdomen with IV contrast Usually Not Appropriate ☢☢☢

Variant: 2   Adult. Liver transplant. Postoperative complications, suspected vascular etiology. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US duplex Doppler abdomen Usually Appropriate O
CT abdomen with IV contrast Usually Appropriate ☢☢☢
CTA abdomen with IV contrast Usually Appropriate ☢☢☢
CT abdomen with IV contrast multiphase Usually Appropriate ☢☢☢☢
MRI abdomen without and with IV contrast May Be Appropriate O
CT abdomen without and with IV contrast May Be Appropriate ☢☢☢☢
US abdomen Usually Not Appropriate O
Radiography abdomen Usually Not Appropriate ☢☢
MRI abdomen without and with IV contrast with MRCP Usually Not Appropriate O
MRI abdomen without IV contrast Usually Not Appropriate O
MRI abdomen without IV contrast with MRCP Usually Not Appropriate O
CT abdomen without IV contrast Usually Not Appropriate ☢☢☢

Variant: 3   Adult. Liver transplant. Postoperative complications, suspected biliary etiology. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US abdomen Usually Appropriate O
US duplex Doppler abdomen Usually Appropriate O
MRI abdomen without and with hepatobiliary contrast Usually Appropriate O
MRI abdomen without and with IV contrast with MRCP Usually Appropriate O
MRI abdomen without IV contrast with MRCP Usually Appropriate O
MRI abdomen without and with IV contrast May Be Appropriate O
CT abdomen with IV contrast May Be Appropriate ☢☢☢
CT abdomen with IV contrast multiphase May Be Appropriate ☢☢☢☢
Radiography abdomen Usually Not Appropriate ☢☢
MRI abdomen without IV contrast Usually Not Appropriate O
CT abdomen without IV contrast Usually Not Appropriate ☢☢☢
CT abdomen without and with IV contrast Usually Not Appropriate ☢☢☢☢

Variant: 4   Adult. Post liver transplant. Surveillance.
Procedure Appropriateness Category Relative Radiation Level
MRI abdomen without and with hepatobiliary contrast Usually Appropriate O
MRI abdomen without and with IV contrast Usually Appropriate O
MRI abdomen without and with IV contrast with MRCP Usually Appropriate O
CT abdomen with IV contrast multiphase Usually Appropriate ☢☢☢☢
US abdomen May Be Appropriate (Disagreement) O
US duplex Doppler abdomen May Be Appropriate (Disagreement) O
MRI abdomen without IV contrast May Be Appropriate O
MRI abdomen without IV contrast with MRCP May Be Appropriate O
CT abdomen with IV contrast May Be Appropriate ☢☢☢
CT abdomen without and with IV contrast May Be Appropriate ☢☢☢☢
Radiography abdomen Usually Not Appropriate ☢☢
CT abdomen without IV contrast Usually Not Appropriate ☢☢☢
FDG-PET/CT skull base to mid-thigh Usually Not Appropriate ☢☢☢☢

Panel Members
Shaun A. Wahab, MDa; Abhinav Vij, MD, MPHb; Alice Fung, MDc; Mustafa R. Bashir, MDd; Brooks D. Cash, MDe; Elizabeth M. Hecht, MDf; A. Tuba Karagulle Kendi, MDg; Brendan M. McGuire, MDh; Gregory K. Russo, MDi; Elainea N. Smith, MDj; Kiran H. Thakrar, MDk; Lisa B. VanWagner, MD, MScl; Atif Zaheer, MDm; Kathryn J. Fowler, MDn.
Summary of Literature Review
Introduction/Background
Special Imaging Considerations
Initial Imaging Definition

Initial imaging is defined as imaging at the beginning of the care episode for the medical condition defined by the variant. More than one procedure can be considered usually appropriate in the initial imaging evaluation when:

  • There are procedures that are equivalent alternatives (i.e., only one procedure will be ordered to provide the clinical information to effectively manage the patient’s care)

OR

  • There are complementary procedures (i.e., more than one procedure is ordered as a set or simultaneously wherein each procedure provides unique clinical information to effectively manage the patient’s care).
Discussion of Procedures by Variant
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
A. CT Abdomen with IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
B. CT Abdomen with IV Contrast Multiphase
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
C. CT Abdomen without and with IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
D. CT Abdomen without IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
E. CTA Abdomen with IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
F. MRI Abdomen without and with IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
G. MRI Abdomen without and with IV Contrast with MRCP
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
H. MRI Abdomen without IV Contrast
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
I. MRI abdomen without IV contrast with MRCP
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
J. Radiography Abdomen
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
K. US Abdomen
Variant 1: Adult. Liver transplant. Immediate postoperative imaging. Initial imaging.
L. US Duplex Doppler Abdomen
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
A. CT Abdomen with IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
B. CT Abdomen with IV Contrast Multiphase
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
C. CT Abdomen Without and With IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
D. CT Abdomen Without IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
E. CTA Abdomen With IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
F. MRI Abdomen Without and With IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
G. MRI abdomen without and with IV contrast with MRCP
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
H. MRI Abdomen Without IV Contrast
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
I. MRI Abdomen Without IV Contrast with MRCP
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
J. Radiography Abdomen
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
K. US Abdomen
Variant 2: Adult. Liver transplant. Postoperative complications. Suspected vascular etiology. Initial imaging.
L. US Duplex Doppler Abdomen
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
A. CT Abdomen With IV Contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
B. CT Abdomen With IV Contrast Multiphase
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
C. CT Abdomen Without and With IV Contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
D. CT Abdomen Without IV Contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
E. MRI abdomen without and with hepatobiliary contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
F. MRI Abdomen Without and With IV Contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
G. MRI Abdomen Without and With IV Contrast with MRCP
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
H. MRI Abdomen Without IV Contrast
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
I. MRI Abdomen Without IV Contrast with MRCP
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
J. Radiography Abdomen
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
K. US Abdomen
Variant 3: Adult. Liver transplant. Postoperative complications. Suspected biliary etiology. Initial imaging.
L. US Duplex Doppler Abdomen
Variant 4: Adult. Post liver-transplant. Surveillance.
Variant 4: Adult. Post liver-transplant. Surveillance.
A. CT Abdomen With IV Contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
B. CT Abdomen With IV Contrast Multiphase
Variant 4: Adult. Post liver-transplant. Surveillance.
C. CT abdomen without and with IV contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
D. CT Abdomen Without IV Contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
E. FDG-PET/CT Skull Base to Mid-Thigh
Variant 4: Adult. Post liver-transplant. Surveillance.
F. MRI Abdomen Without and With Hepatobiliary Contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
G. MRI Abdomen Without and With IV Contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
H. MRI Abdomen Without and With IV Contrast With MRCP
Variant 4: Adult. Post liver-transplant. Surveillance.
I. MRI Abdomen Without IV Contrast
Variant 4: Adult. Post liver-transplant. Surveillance.
J. MRI Abdomen Without IV Contrast With MRCP
Variant 4: Adult. Post liver-transplant. Surveillance.
K. Radiography Abdomen
Variant 4: Adult. Post liver-transplant. Surveillance.
L. US Abdomen
Variant 4: Adult. Post liver-transplant. Surveillance.
M. US Duplex Doppler Abdomen
Summary of Highlights
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.

Gender Equality and Inclusivity Clause
The ACR acknowledges the limitations in applying inclusive language when citing research studies that predates the use of the current understanding of language inclusive of diversity in sex, intersex, gender, and gender-diverse people. The data variables regarding sex and gender used in the cited literature will not be changed. However, this guideline will use the terminology and definitions as proposed by the National Institutes of Health.
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

Potential adverse health effects associated with radiation exposure are an important factor to consider when selecting the appropriate imaging procedure. Because there is a wide range of radiation exposures associated with different diagnostic procedures, a relative radiation level (RRL) indication has been included for each imaging examination. The RRLs are based on effective dose, which is a radiation dose quantity that is used to estimate population total radiation risk associated with an imaging procedure. Patients in the pediatric age group are at inherently higher risk from exposure, because of both organ sensitivity and longer life expectancy (relevant to the long latency that appears to accompany radiation exposure). For these reasons, the RRL dose estimate ranges for pediatric examinations are lower as compared with those specified for adults (see Table below). Additional information regarding radiation dose assessment for imaging examinations can be found in the ACR Appropriateness Criteria® Radiation Dose Assessment Introduction document.

Relative Radiation Level Designations

Relative Radiation Level*

Adult Effective Dose Estimate Range

Pediatric Effective Dose Estimate Range

O

0 mSv

 0 mSv

<0.1 mSv

<0.03 mSv

☢☢

0.1-1 mSv

0.03-0.3 mSv

☢☢☢

1-10 mSv

0.3-3 mSv

☢☢☢☢

10-30 mSv

3-10 mSv

☢☢☢☢☢

30-100 mSv

10-30 mSv

*RRL assignments for some of the examinations cannot be made, because the actual patient doses in these procedures vary as a function of a number of factors (e.g., region of the body exposed to ionizing radiation, the imaging guidance that is used). The RRLs for these examinations are designated as “Varies.”

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.