aium practice guideline

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AIUM Practice Guideline for the Performance of an

Ultrasound Examinationof the Abdomen and/or

Retroperitoneum

2012 by the American Institute of Ultrasound in Medicine

Guideline developed in conjunction with the American College of Radiology (ACR),the Society for Pediatric Radiology (SPR), and the Society of Radiologists in Ultrasound (SRU).

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The American Institute of Ultrasound in Medicine (AIUM) is a multidis-

ciplinary association dedicated to advancing the safe and effective use

of ultrasound in medicine through professional and public education,

research, development of guidelines, and accreditation. To promote

this mission, the AIUM is pleased to publish, in conjunction with the

American College of Radiology (ACR), the Society for Pediatric

Radiology (SPR), and the Society of Radiologists in Ultrasound (SRU),

this AIUM Practice Guideline for the Performance of an Ultrasound

Examination of the Abdomen and/or Retroperitoneum. We are indebt-

ed to the many volunteers who contributed their time, knowledge, and

energy to bringing this document to completion.

The AIUM represents the entire range of clinical and basic science

interests in medical diagnostic ultrasound, and, with hundreds of

volunteers, the AIUM has promoted the safe and effective use of ultra-

sound in clinical medicine for more than 50 years. This document and

others like it will continue to advance this mission.

Practice guidelines of the AIUM are intended to provide the medical

ultrasound community with guidelines for the performance and

recording of high-quality ultrasound examinations. The guidelines

reflect what the AIUM considers the minimum criteria for a complete

examination in each area but are not intended to establish a legal

standard of care. AIUM-accredited practices are expected to generally

follow the guidelines with recognition that deviations from theseguidelines will be needed in some cases, depending on patient needs

and available equipment. Practices are encouraged to go beyond the

guidelines to provide additional service and information as needed.

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Original copyright 1994; revised 2002, 2007, 2008, 2012AIUM PRACTICE GUIDELINESUltrasound Examination of the Abdomen and/or Retroperitoneum

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Cite this guideline as follows:

American Institute of Ultrasound in Medicine. AIUM practice guideline for the performance of an

ultrasound examination of the abdomen and/or retroperitoneum. J Ultrasound Med 2012; 31: 13011312.


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I. Introduction

The clinical aspects contained in specific sections of this guideline (Introduction,

Indications/Contraindicatons, Specifications for Individual Examinations, and EquipmentSpecifications) were developed collaboratively by the American Institute of Ultrasound inMedicine (AIUM), the American College of Radiology (ACR), the Society for PediatricRadiology (SPR), and the Society of Radiologists in Ultrasound (SRU). Qualifications andResponsibilities of Personnel, Written Request for the Examination, Documentation, andQuality Control and Improvement, Safety, Infection Control, and Patient Education varyamong the organizations and are addressed by each separately.

This guideline has been developed to assist practitioners performing ultrasound studies of theabdomen and/or retroperitoneum. Sonography is a proven and useful procedure for the eval-uation of many structures within these anatomic areas. Depending on the clinical indications,an examination may include the entirety of the abdomen and/or retroperitoneum, a single

organ, or several organs. A combination of structures may be imaged because of location(eg, upper abdominal scan and right upper quadrant organs) or function (eg, biliary system[liver, gallbladder, and bile ducts] and both kidneys). For some patients, more focused exami-nations may be appropriate for evaluating specific clinical indications or to follow up a knownabnormality. In some cases, additional and/or specialized examinations may be necessary(eg, spectral, color, and/or power Doppler imaging). Although it is not possible to detect everyabnormality using an ultrasound examination of the abdomen and/or retroperitoneum, adher-ence to the following guideline will maximize the probability of detecting abnormalities.

Throughout this guideline, references to Doppler evaluation may include spectral, color, orpower Doppler imaging individually or in any combination. Whenever a long-axis view isindicated, it could be either a sagittal or coronal plane.

II. Qualifications and Responsibilities of Personnel

See the AIUM Official Statement Training Guidelines for Physicians Who Evaluate and InterpretDiagnostic Ultrasound Examinationsand the AIUM Standards and Guidelines for the Accreditationof Ultrasound Practices.

III. Indications/Contraindications

Indications for an ultrasound examination of the abdomen and/or retroperitoneum includebut are not limited to1:

A. Abdominal, flank, and/or back pain.

B. Signs or symptoms that may be referred from the abdominal and/or retroperitonealregions such as jaundice or hematuria.

C. Palpable abnormalities such as an abdominal mass or organomegaly.

Effective April 1, 2012AIUM PRACTICE GUIDELINESUltrasound Examination of the Abdomen and/or Retroperitoneum

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D. Abnormal laboratory values or abnormal findings on other imaging examinationssuggestive of abdominal and/or retroperitoneal pathology.

E. Follow-up of known or suspected abnormalities in the abdomen and/or retroperitoneum.F. Search for metastatic disease or an occult primary neoplasm.

G. Evaluation of suspected congenital abnormalities.

H. Abdominal trauma.

I. Pretransplantation and posttransplantation evaluation.

J. Planning for and guiding an invasive procedure.

K. Searching for the presence of free or loculated peritoneal and/or retroperitoneal fluid.

L. Suspicion of hypertrophic pyloric stenosis or intussusceptions.

M. Evaluation of a urinary tract infection.

An abdominal and/or retroperitoneal ultrasound examination should be performed whenthere is a valid medical reason. There are no absolute contraindications.

IV. Written Request for the Examination

The written or electronic request for an ultrasound examination should provide sufficientinformation to allow for the appropriate performance and interpretation of the examination.

The request for the examination must be originated by a physician or another appropriatelylicensed health care provider or under the physicians or providers direction. The accompany-ing clinical information should be provided by a physician or another appropriate health careprovider familiar with the patients clinical situation and should be consistent with relevant

legal and local health care facility requirements.

V. Specifications for Individual Examinations

Spectral, color, and power Doppler imaging may be useful to differentiate vascular from non-vascular structures in any location. Measurements should be considered for any abnormal area.2

1. Liver

The examination of the liver should include long-axis and transverse views. The liverparenchyma should be evaluated for focal and/or diffuse abnormalities. If possible, theechogenicity of the liver should be compared with that of the right kidney. In addition,the following should be imaged38:

a. The major hepatic and perihepatic vessels, including the inferior vena cava (IVC),the hepatic veins, the main portal vein, and, if possible, the right and left branches ofthe portal vein.


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b. The hepatic lobes (right, left, and caudate) and, if possible, the right hemidiaphragmand the adjacent pleural space.

c. For vascular examinations of the native or transplanted liver, Doppler evaluation shouldbe used to document blood flow characteristics and blood flow direction. The struc-tures that may be examined include the main and intrahepatic arteries, the hepaticveins, the main and intrahepatic portal veins, the intrahepatic portion of the IVC,collateral venous pathways, and transjugular intrahepatic portosystemic shunt stents.

2. Gallbladder and Biliary Tract

A routine gallbladder examination should be conducted on an adequately distended gallblad-der whenever possible. In most cases, fasting before elective examination will permit adequatedistension of a normally functioning gallbladder. In infants and children, fasting may not benecessary in all cases. The gallbladder evaluation should include long-axis and transverse viewsobtained in the supine position. Other positions such as left lateral decubitus, erect, and pronemay be helpful to evaluate the gallbladder and its surrounding areas completely. Measurementsmay aid in determining gallbladder wall thickening. If the patient presents with pain, tender-ness to transducer compression should be assessed.

The intrahepatic ducts can be evaluated by obtaining views of the liver demonstrating the rightand left branches of the portal vein. Doppler imaging may be used to differentiate hepaticarteries and portal veins from bile ducts. The intrahepatic and extrahepatic bile ducts shouldbe evaluated for dilatation, wall thickening, intraluminal findings, and other abnormalities.The bile duct in the porta hepatis should be measured and documented. When visualized, thedistal common bile duct in the pancreatic head should be evaluated.912

3. Pancreas

Whenever possible, all portions of the pancreashead, uncinate process, body, and tailshould be identified. Orally administered water or a contrast agent may afford better visualiza-tion of the pancreas. The following should be assessed in the examination of the pancreas1215:

a. Parenchymal abnormalities.

b. The distal common bile duct in the region of the pancreatic head.

c. The pancreatic duct for dilatation and any other abnormalities, with dilatation confirmedby measurement.

d. The peripancreatic region for adenopathy and/or fluid.

4. Spleen

Representative views of the spleen in long-axis and transverse projections should be obtained.Splenic length measurement may be helpful in assessing enlargement. Echogenicity of the leftkidney should be compared to splenic echogenicity when possible. An attempt should be madeto demonstrate the left hemidiaphragm and the adjacent pleural space. 1619


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5. Bowel

The bowel may be evaluated for wall thickening, dilatation, muscular hypertrophy, masses,

vascularity, and other abnormalities. Sonography of the pylorus and surrounding structuresmay be indicated in evaluation of the vomiting infant. Graded compression sonography aids inthe visualization of the appendix and other bowel loops. Measurements may aid in determin-ing bowel wall thickening.2026

6. Peritoneal Fluid

Evaluation for free or loculated peritoneal fluid should include documentation of the extentand location of any fluid identified.

For evaluating peritoneal spaces for bleeding after traumatic injury, particularly blunt trauma,the examination known as focused abdominal sonography for trauma (FAST, also known asfocused assessment with sonography for trauma) may be performed.27 The objective of the

abdominal portion of the FAST examination is to screen the abdomen for free fluid.Longitudinal and transverse plane images should be obtained in the right upper quadrantthrough the area of the liver with attention to fluid collections peripheral to the liver and in thesubhepatic space. Longitudinal and transverse plane images should be obtained in the leftupper quadrant through the area of the spleen with attention to fluid collections peripheral tothe spleen. Longitudinal and transverse images should be obtained at the periphery of the leftand right abdomen in the areas of the left and right paracolic gutters for evidence of free fluid.Longitudinal and transverse midline images of the pelvis are obtained to evaluate for free pelvicfluid. Analysis through a fluid-filled bladder (which if necessary can be filled through a Foleycatheter, when possible) may help in evaluation of the pelvis.

7. Abdominal Wall

The examination should include images of the abdominal wall in the location of symptoms orsigns. The relationship of any identified mass with the peritoneum should be demonstrated.Any defect in the peritoneum and abdominal wall musculature should be documented. Thepresence or absence of bowel, fluid, or other tissue contained within any abdominal wall defectshould be noted. Images obtained in upright position and/or with use of the Valsalva maneu-ver may be helpful. Doppler examination may be useful to define the relationship of bloodvessels with a detected mass.

8. Kidneys

An examination of native or transplanted kidneys should include long-axis and transverse viewsof the kidneys. The cortices and renal pelvises should be assessed. A maximum measurement

of renal length should be recorded for both kidneys. Decubitus, prone, or upright positioningmay provide better images of the native kidneys. When possible, renal echogenicity should becompared to the adjacent liver or spleen. The kidneys and perirenal regions should be assessedfor abnormalities.6,2835


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For a vascular examination of native or transplanted kidneys, Doppler imaging can be used:

a. To assess renal arterial and venous patency.

b. To evaluate suspected renal artery stenosis. For this application, angle-adjusted measure-ments of the peak systolic velocity should be made proximally, centrally, and distally in theextrarenal portion of the main renal arteries when possible. The peak systolic velocity ofthe adjacent aorta should also be documented for calculating the renal to aortic peaksystolic velocity ratio. Spectral Doppler evaluation of the intrarenal arteries may be ofvalue as indirect evidence of proximal stenosis in the main renal artery.

c. For vascular examinations of transplanted kidneys, Doppler evaluation should be used todocument vascular patency and blood flow characteristics. The structures that may beexamined include the main renal artery and vein, arterial and venous anastomoses, the iliacartery and vein, and the intrarenal arteries.

9. Urinary Bladder and Adjacent Structures

When performing a complete ultrasound evaluation of the urinary tract, transverse and longi-tudinal images of the distended urinary bladder and its wall should be included, if possible.Bladder lumen or wall abnormalities should be noted. Dilatation or other distal ureteralabnormalities should be documented. Transverse and longitudinal scans may be used todemonstrate any postvoid residual, which may be quantitated and reported.

10. Adrenal Glands

When possible, usually in the neonate or young infant, long-axis and transverse images ofthe adrenal glands may be obtained. Normal adrenal glands are less commonly shown byultrasound imaging in adults.32

11. Aorta

Representative images of the aorta should be obtained.36When evaluation of the aorta is specif-ically requested, see theAIUM Practice Guideline for the Performance of Diagnostic and ScreeningUltrasound of the Abdominal Aorta.

12. Inferior Vena Cava

Representative images of the IVC should be obtained. Patency and abnormalities may beevaluated with Doppler imaging. Vena cava filters, interruption devices, and catheters mayneed to be localized with respect to the hepatic and/or renal veins.37


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VI. Documentation

Adequate documentation is essential for high-quality patient care. There should be a perma-

nent record of the ultrasound examination and its interpretation. Images of all appropriateareas, both normal and abnormal, should be recorded. Variations from normal size shouldbe accompanied by measurements. Images should be labeled with the patient identification,facility identification, examination date, and side (right or left) of the anatomic site imaged.An official interpretation (final report) of the ultrasound findings should be included in thepatients medical record. Retention of the ultrasound examination should be consistent bothwith clinical needs and with relevant legal and local health care facility requirements.

Reporting should be in accordance with theAIUM Practice Guideline for Documentation of anUltrasound Examination.

VII. Equipment SpecificationsAbdomen and/or retroperitoneum sonographic studies should be conducted with real-timescanners, preferably using sector or linear transducers. The equipment should be adjusted tooperate at the highest clinically appropriate frequency, realizing that there is a trade-offbetween resolution and beam penetration. For most preadolescent pediatric patients, meanfrequencies of 5 MHz or greater are preferred, and in neonates and small infants a higher-frequency transducer is often necessary. For adults, mean frequencies between 2 and 5 MHzare most commonly used. When Doppler studies are performed, the Doppler frequency maydiffer from the imaging frequency. Image quality should be optimized while keeping total ultra-sound exposure as low as reasonably achievable.

VIII. Quality Control and Improvement, Safety, Infection Control,and Patient Education

Policies and procedures related to quality control, patient education, infection control, andsafety should be developed and implemented in accordance with the AIUM Standards andGuidelines for the Accreditation of Ultrasound Practices.

Equipment performance monitoring should be in accordance with the AIUM Standards andGuidelines for the Accreditation of Ultrasound Practices.

IX. ALARA PrincipleThe potential benefits and risks of each examination should be considered. The ALARA(as low as reasonably achievable) principle should be observed when adjusting controls thataffect the acoustic output and by considering transducer dwell times. Further details onALARA may be found in the AIUM publicationMedical Ultrasound Safety, Second Edition.


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Acknowledgments

This guideline was revised by the American Institute of Ultrasound in Medicine (AIUM) in

collaboration with the American College of Radiology (ACR), the Society for PediatricRadiology (SPR), and the Society of Radiologists in Ultrasound (SRU) according to theprocess described in the AIUM Clinical Standards Committee Manual.

Collaborative Committee: Members represent their societies in the initial and final revisionof this guideline.

ACR

Beverly E. Hashimoto, MD, ChairSara J. Abramson, MD

Brian D. Coley, MD

Robert D. Harris, MD, MPH

Marta Hernanz-Schulman, MD

Beverley Newman, MD, BCh, BSc

Robert M. Sinow, MD, MD

Maryellen R. M. Sun, MD

AIUM

Lin Diacon, MD

Judy A. Estroff, MD

David M. Paushter, MD

SRU

Teresita L. Angtuaco, MDRick I. Feld, MD

Francisco A. Quiroz, MD

Mitchell E. Tublin, MD

SPR

Leann E. Linam, MD

Henrietta K. Rosenberg, MD

David M. Weinert, MD

AIUM Clinical Standards Committee

Leslie Scoutt, MD, Chair

Joseph Wax, MD, Vice ChairHarris L. Cohen, MD

Lin Diacon, MD, RDMS, RPVI

J. Christian Fox, MD, RDMS

Pat Fulgham, MD


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Charlotte Henningsen, MS, RT, RDMS, RVT

Adam Hiett, MD, RDMS

Lars Jensen, MDAnthony Odibo, MD

Steven Perlmutter, MD

Olga Rasmussen, RDMS

Deborah Rubens, MD

Khaled Sakhel, MD

Shia Salem, MD

Jay Smith, MD

Lami Yeo, MD

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