Objectives. Hepatobiliary Ultrasound: Anatomy, Technique, Pathology. RUQ: Normal Anatomy. Emergency Ultrasound: Gallbladder Location

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1 Hepatobiliary Ultrasound: Anatomy, Technique, Pathology Laleh Gharahbaghian, MD FAAEM Associate Director, EM Ultrasound Co-Director, EM Ultrasound Fellowship Stanford University Medical Center Seric Cusick, MD RDMS Director of Emergency Ultrasound Fellowship Director, Emergency Ultrasound University of California, Davis Objectives Review anatomy and landmarks Scanning Technique: Gallbladder Evaluation Transducer choice, orientation Scanning: transverse and longitudinal views Measurements: GB, anterior GB wall, CBD GB Pathology Liver Pathology Pitfalls and Tricks of the Trade RUQ: Normal Anatomy Liver: used as acoustic window; ducts and vessels Biliary ducts: CBD Bowel: duodenum Kidney: retroperitoneal (posterior) GB: mobile, folds, contracts, anatomical variations General Location RUQ Subcostal Emergency Ultrasound: Gallbladder Location Lies within fossa Posterior wall approximates duodenum Therefore, NOTE: the gallbladder long and short does not axis lie of within the gallbladder a standard anatomic may not lie plane, within and the longitudinal may be found and in transverse many different planes projections of the body

2 RUQ: Abnormal GB: Normal Anatomy GB length: 7-10cm; width 2-3cm Anterior GB wall: <4mm, linear echo CBD: <7mm, above portal vein Main Lobar Fissure (MLF): between GB and portal vein MLF Anterior GB wall Technique Patient Position: Supine or Left lateral decubitus Transducer: Curved, low frequency probe Indicator to patient s right and then toward patient s head (transverse / longitudinal view) Start at Xiphoid process and travel laterally along subcostal margin, flattening probe Once find GB: fan through it in two orthogonal planes Transverse Poor quality image: gas Left lateral decubitus Technique Thin patients: GB can be elongated, anterior, lower in abdomen flatten probe along abdomen Obese patients: GB can be higher in abdomen X minus 7 approach 7cm Longitudinal xyphoid process

3 Transverse Longitudinal Anatomical Variants GB fold(s) Pathology: Gallstones Echogenic Shadow Mobile Single or multiple Varying sizes

4 Pathology: Gallstones WES sign WES sign W - wall E - Echo S - Shadow = contracted GB full of stones

5 Pathology: Cholecystitis FINDINGS: Pericholecystic fluid Thickened GB wall Sonographic Murphy s CBD Dilatation Sludge

6 Pathology: Thick GB wall Main etiology: CHOLECYSTITIS Normal Abnormal HTN renal disease multiple myeloma adenomyomatosis Tumors CHF hepatitis ascites alcoholic liver disease hypoproteinemia hypoalbuminemia pericholecystic Pathology: Biliary Ducts Biliary ducts provide information regarding obstruction Common Bile Duct: Dilated Biliary Ducts located above portal vein follow MLF to CBD Tip: Use Color Doppler box to differentiate biliary ducts from hepatic vessels Portal longitudinal Finding the CBD...

7 Finding the CBD... Dilated Biliary Ducts Pitfalls Mistaking Duodenum with GB Mistaking GB fold for stone/mass Gas Scatter - put patient in LLD WES sign - not knowing what you see when you see it Tricks of the Trade: Scanning Tips Obtaining window - small liver, gas scatter, anterior GB can result in difficult visualization patient positioning, flattening probe System controls - adjust Gain, Depth to maximize image quality

8 When you can t find the Gallbladder... Left Lateral Decubitus position Try between the ribs (X minus 7) Try RUQ of FAST view (transducer at midaxillary line; indicator toward head) move probe anteriorly kidney leaves view, GB comes into view Other things you may see... Liver abscess Other things you may see... Other things you may see... Liver cysts TIPS free fluid

9 Other things you may see... Liver cancer Summary Point-of-care ultrasound of the hepatobiliary system may aid in the care of emergency department patients Evaluation for gallstones and secondary features of cholecystitis may be facilitated by sonographic techniques and the appreciation of key pitfalls References Blaivas M, Harwood RA, Lambert MJ. Decreasing length of stay with emergency ultrasound examination of the gallbladder. Acad Emerg Med. Oct 1999;6(10): Bree RL. Further observations on the usefulness of the sonographic Murphy sign in the evaluation of suspected acute cholecystitis. J Clin Ultrasound. Mar-Apr 1995;23(3): Durston W, Carl ML, Guerra W, et al. Comparison of quality and cost-effectiveness in the evaluation of symptomatic cholelithiasis with different approaches to ultrasound availability in the ED. Am J Emerg Med. Jul 2001;19(4): Gaspari RJ, Dickman E, Blehar D. Learning curve of bedside ultrasound of the gallbladder. J Emerg Med. Jul 2009;37(1): Jang T, Aubin C, Naunheim R. Minimum training for right upper quadrant ultrasonography. Am J Emerg Med. Oct 2004;22(6): 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. Miller AH, Pepe PE, Brockman CR, Delaney KA. ED ultrasound in hepatobiliary disease. J Emerg Med. Jan 2006;30(1): Ralls PW, Colletti PM, Lapin SA, et al. Real-time sonography in suspected acute cholecystitis. Prospective evaluation of primary and secondary signs. Radiology. Jun 1985;155(3): Ralls PW, Halls J, Lapin SA, Quinn MF, Morris UL, Boswell W. Prospective evaluation of the sonographic Murphy sign in suspected acute cholecystitis. J Clin Ultrasound. Mar 1982;10(3): Rosen CL, Brown DF, Chang Y, et al. Ultrasonography by emergency physicians in patients with suspected cholecystitis. Am J Emerg Med. Jan 2001;19(1): Scruggs W, Fox JC, Potts B, et al. Accuracy of ED Bedside Ultrasound for Identification of gallstones: retrospective analysis of 575 studies. West J Emerg Med. Jan 2008;9(1):1-5. Shea JA, Berlin JA, Escarce JJ, et al. Revised estimates of diagnostic test sensitivity and specificity in suspected biliary tract disease. Arch Intern Med. Nov ;154(22): Summers SM, Scruggs W, Menchine MD, et al. A Prospective Evaluation of Emergency Department Bedside Ultrasonography for the Detection of Acute Cholecystitis. Ann Emerg Med. Feb 4.

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