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Clinical Procedures > Radiology
Bedside Ultrasonography, Gallbladder Disease
Article Last Updated: Jan 7, 2008
AUTHOR AND EDITOR INFORMATION
Section 1 of 12  
Author: Timothy Jang, MD, Director of Emergency Ultrasound, Olive View-UCLA Medical Center, Clinical Faculty, Division of Emergency Medicine, Washington University School of Medicine
Editors: James Quan-Yu Hwang, MD, Attending Physician, Department of Emergency Medicine, Brigham & Women's Hospital; Clinical Instructor, Harvard Medical School; Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc; Rick Kulkarni, MD, Medical Director, Assistant Professor of Surgery, Section of Emergency Medicine, Yale-New Haven Hospital
Author and Editor Disclosure
Synonyms and related keywords:
bedside ultrasound, bedside ultrasonography, gall bladder, gall stone, gallbladder disease, gallbladder, gallstones, biliary disease, biliary cancer, biliary ultrasound, focused emergency biliary sonography, FEBS, cystic duct, biliary ultrasonography, focused bedside biliary sonography, bedside sonography
Cholelithiasis is a common cause of abdominal pain among patients who present to the emergency department or other outpatient clinical setting; it affects over 15 million people in the United States. Unfortunately, clinical examinations and laboratory evaluations lack the necessary sensitivity and specificity to accurately diagnose cholecystitis without further testing.1 Focused emergency or bedside ultrasonography (US) is an important and valuable diagnostic tool that can often facilitate timely diagnosis for these patients.
The benefits of focused bedside biliary sonography include the following: - Decreases the time to diagnosis for cholelithiasis and cholecystitis2
- Helps accurately diagnose biliary pathology2
- Helps assess the degree of obstruction in choledocholithiasis
- Can help diagnose gallstones definitively, which makes alternative diagnoses such as symptomatic aortic aneurysm or obstructive uropathy less likely
- Can be performed quickly at the bedside
- Can provide radiographic corroboration of physical examination findings
- Is safe in pregnant patients and children and requires less radiation than either hepatobiliary iminodiacetic acid (HIDA) scans (cholescintigraphy) or magnetic resonance imaging (MRI)3
For more information, see the Medscape Gallbladder and Biliary Disease Resource Center, and for a discussion of the management of biliary stones, see the Medscape CME activity, New Guidelines Address Management of Common Bile Duct Stones.
Indications for focused bedside biliary sonography include the following:
- Abdominal pain associated with meals
- Colicky right upper quadrant or epigastric pain
- Jaundice
- Atypical right-sided chest pain
- Abnormal liver function test results
While hepatic malignancy can often be identified by focused emergency biliary sonography, this is outside the scope of bedside ultrasonography. Patients with suspected hepatic malignancy should receive a CT scan, if clinically indicated, or be referred to a radiologist for further evaluation.
Performance of focused bedside biliary sonography should not delay the initiation of emergent treatments such as intravenous fluids, antibiotics, or pressors when indicated. Although ongoing resuscitation and extremis are not contraindications, this procedure can be difficult to perform in such situations.
Anesthesia is generally not necessary for sonographic evaluation. For improved patient comfort, consider using warmed ultrasound-conducting gel, if available.
- Ultrasound machine
- Ultrasound-conducting gel
Patients should be evaluated in the supine position but can be moved to the upright, standing, or left lateral decubitus positions for improved visualization. Male patients should have their entire right hemithorax exposed for the examination; for female patients, optimal exposure must be balanced with appropriate draping of potentially sensitive areas.
Relevant anatomy
The gallbladder is superior and anterior to the right kidney but inferior to the liver. It typically lies between the right and quadrate lobes of the liver in a slightly oblique position. Landmarks for the gallbladder are the undivided right portal vein and the main lobar fissure. The main lobar fissure is a bright hyperechoic line that extends from the right portal vein to the gallbladder fossa. The main lobar fissure is the functional division of the liver (divides right and left lobes) and is seen in most patients; however, it may be short or absent in some patients. The gallbladder neck tapers into the cystic duct. The common bile duct (CBD) travels anterior to the portal vein and right of the hepatic artery.
Components of examination
Focused bedside biliary sonography should include transverse and longitudinal views of the gallbladder with clear anatomical relationship to the liver, kidney, and portal vein for unambiguous identification. In addition, a dependent view (upright, standing, or left lateral decubitus) should also be obtained when stones are seen to determine if they are mobile.
Technique
- With the patient in the supine position, place the probe in the right upper quadrant.
- Once the gallbladder is clearly identified, obtain longitudinal and transverse views of the gallbladder.
Longitudinal probe placement for biliary ultrasonography with the indicator pointed toward the patient's head (cephalad).
Longitudinal view of gallbladder.
Transverse probe placement for biliary ultrasonography with the indicator pointing to the patient's right. - If stones are seen, obtain a dependent view (upright, standing, or left lateral decubitus) to assess the mobility of the stones.
Left lateral decubitus probe placement.
Left lateral decubitus view of gallbladder. - Use the liver as an acoustic window. If the gallbladder cannot be visualized (because of bowel gas or a more cephalad location of gallbladder), try moving laterally or superiorly. Moving the probe cephalad may necessitate scanning through or between the right lower ribs; in such cases, consider switching to a phased array probe, which has a smaller footprint.
View of gallbladder using the liver as an acoustic window.
Ultrasonographic criteria
- Gallstones should produce acoustic shadows.
View of gallstone. - Gallstones should demonstrate gravitational dependency and mobility.
View of gallstone. - Cholesterol stones and stones smaller than 1 mm may not produce prominent shadows; they may instead form a posterior hazy appearance.
- Sludge is less echogenic than stones, does not shadow, forms a fluid level, and moves slowly compared to stones.
- Findings that suggest acute cholecystitis include gallbladder wall thickening (>4 mm), double wall sign, pericholecystic fluid, or a sonographic Murphy sign.
Gallbladder wall thickening with edema.
Gallbladder wall thickening with edema, seen in transverse view. - Common bile duct diameters range from 4-10 mm, depending on a patient’s age (normal is 3-4 mm; add 1 mm for every 10 years after age 40 years). A dilated CBD can suggest choledocholithiasis, cholecystitis, or biliary obstruction.
View of gallstone with dilation of cystic duct.
- If the gallbladder cannot be visualized, consider repositioning the patient into an upright, standing, or left lateral decubitus position.
- If the patient is very thin or has a very anterior gallbladder, try using a higher frequency probe (5 MHz as opposed to 3.5 MHz).
- Gallbladder wall thickening may also be seen in patients with ascites, congestive heart failure (CHF), hypoalbuminemia, chronic liver disease (hepatitis), pancreatitis, or HIV, and may be seen postprandially in patients with a contracted gallbladder.4
- Biliary ductal dilation can also be seen chronically in patients with conditions like Caroli syndrome.
- Nonshadowing, nonmobile, rounded intrabiliary masses tend to be polyps; patients with such masses should receive further imaging, if clinically indicated, or be referred to a radiologist for further workup.
- Most patients with biliary cancer also have gallstones and can develop a calcified wall with focal thickening.5 Calcified gallbladders, also known as porcelain gallbladders, have a high frequency (up to 22%) of association with adenocarcinoma. In patients with calcified gallbladders or with suspected biliary cancer, further evaluation by a radiologist is recommended.
- If cysts or masses are identified, patients should obtain further imaging or be referred to a radiologist for further workup and management.
- Mucosal folds within the gallbladder are common. Caution must be used to not misinterpret them as septae, polyps, or stones.
- Common pitfalls include the following:
- Failure to visualize the entire gallbladder, resulting in missed gallstones
- Overreading artifact (side lobe artifact, edge artifact)
- Misinterpreting shadows
- Overreading poor quality images
No complications are typically associated with this procedure.
| Media file 1:
Longitudinal probe placement for biliary ultrasonography with the indicator pointed toward the patient's head (cephalad). |
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| Media file 2:
Transverse probe placement for biliary ultrasonography with the indicator pointing to the patient's right. |
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| Media file 4:
Left lateral decubitus view of gallbladder. |
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Media type: Ultrasound
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| Media file 6:
View of gallbladder using the liver as an acoustic window. |
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Media type: Ultrasound
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| Media file 9:
Gallbladder wall thickening with edema, seen in transverse view. |
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Media type: Ultrasound
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| Media file 10:
View of gallstone with dilation of cystic duct. |
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Media type: Ultrasound
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- Singer AJ, McCracken G, Henry MC, et al. Correlation among clinical, laboratory, and hepatobiliary scanning findings in patients with suspected acute cholecystitis. Ann Emerg Med. Sep 1996;28(3):267-72. [Medline].
- Kendall JL, Shimp RJ. Performance and interpretation of focused right upper quadrant ultrasound by emergency physicians. J Emerg Med. Jul 2001;21(1):7-13. [Medline].
- Marincek B. Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies. Eur Radiol. Sep 2002;12(9):2136-50. [Medline].
- van Breda Vriesman AC, Engelbrecht MR, Smithuis RH, Puylaert JB. Diffuse gallbladder wall thickening: differential diagnosis. AJR Am J Roentgenol. Feb 2007;188(2):495-501. [Medline].
- Tewari M. Contribution of silent gallstones in gallbladder cancer. J Surg Oncol. Jun 15 2006;93(8):629-32. [Medline].
Bedside Ultrasonography, Gallbladder Disease excerpt Article Last Updated: Jan 7, 2008
Topic originally published: Jan 7, 2008
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