Biliary Ultrasonography Kathleen O Brien MD MPH RDMS Kaiser Permanente South Sacramento

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1 Biliary Ultrasonography Kathleen O Brien MD MPH RDMS Kaiser Permanente South Sacramento 9gObEoAK8wH1A5gGzT2sPb4_1rT3RPas9oj3TPdA9gj0aMKH8NOYEFXq-bLiqT1dZVwE0H7ZToFj_1o1v8lT5SxLIe14QK-_1Ecx3m3snDE4-4zCSADDAsQjq7-CBoKCggIARIEz6gJwAw&ved=0ahUKEwim9uWFrMPLAhUQ0GMKHazFD5IQwg4IGigA&biw=1347&bih=592 NONE 2 Objectives: Discuss clinical indications and questions answered by RUQUS Review of pertinent RUQ anatomy Share techniques & scanning tips Literature to support use of RUQUS Scope of the problem: Abdominal pain accounts for 5-10% of ED visits in US 1/3 of our abdominal pain patients in ED have GB etiologies for their pain 20M Americans have gallstones; ½ M undergo cholecystectomy each year 2 stones SEE MORE PATIENTS! DISPO THEM FASTER! SPEND LESS MONEY! BUT DON T COMPROMISE QUALITY OF CARE. 3 4 *Abdominal pain in the ED: stability and change over 20 years. Powers RD, Guertler AT.Am J Emerg Med. 1995;13(3):301. 1

2 One solution: Current imaging options for AC: HIDA: -highest diagnostic accuracy in older studies - sensitivity 96%, specificity 90% Ultrasound: -sensitivity 88-90%, specificity 80-88% -NPV 95-98% CT: MRI: -helpful for detecting complications - sensitivity 73-99%, specificity 42-74% -similar to u/s test characteristics - MRCP helpful if choledocholithiasis suspected overview 5 nutrition aha moments/ 6 But isn t that why we have radiologists? ED performed RUQ ultrasound shown to be as sensitive and specific for radiology performed RUQ ultrasound for acute cholecystitis! ED physicians often not formally trained in RUQ u/s and test characteristics still acceptable Advantage: increased efficiency, decreased time to diagnosis and disposition Purpose of RUQUS: Evaluate for: Cholelithiasis Acute cholecystitis Obvious liver/biliary pathology Indications: RUQ pain Flank/shoulder/ epigastric pain Ascites Hepatomegaly Jaundice Pancreatitis Sepsis 7 8 2

3 Anatomy Gallbladder is located at the inferior surface of the liver; consists of the fundus, the body and the neck Anatomy Liver The neck of the gallbladder drains into the cystic duct which joins the hepatic duct to form the common bile duct () The portal triad consists of the hepatic artery, common bile duct () and the portal vein The and the hepatic artery lie anterior to the portal vein Gallbladder Duodenum Pancreatic duct Hepatic duct Cystic duct Pancreas Common bile duct Techniques 101: Probe selection Use MHz low frequency abdominal probe

4 13 Techniques 101: SUBcostal approach The probe is placed below the rib cage, lateral to epigastrium Good for avoiding Rib shadows Reliable Sono Murphy s Probe marker to head/r Shoulder hold probe at shallow angle 14 Techniques 101: INTERcostal approach Probe placed in the right anterior axillary line over the lower rib spaces, marker facing to right shoulder/head Slow sweep across the ribs Use the liver as an acoustic window Anchor your hand for stability Aka X minus 7 Techniques 101: Positioning in Left Lateral Decubitus Techniques 101: Can place probe subcostal or intercostal GB should move anteriorly Use the liver as acoustic window Slow sweep along costal margin -Always scan the entire gallbladder in two planes: Longitudinal Transverse -Slowly fan through entire gallbladder in these two planes

5 What should you see: GB long Gallbladder anterior anterior Portal vein head feet supine head feet posterior Left lateral decubitus 18 posterior anterior What should you see: GB short anterior head QuickTime and a Animation decompressor are needed to see this picture. feet supine right left posterior Normal Gallbladder in long axis 20 Left lateral decubitus posterior 5

6 anterior Normal variants of the Gallbladder Pharyngian cap: The fundus is folded onto the body right left Septate GB: thin septa inside gallbladder posterior Normal Gallbladder in short axis 22 The highly elusive Common Bile Duct... Exclamation point sign lies anterior to portal vein and next to hepatic artery -Color Doppler can help identify vascular structures Normal <7mm. - dilates with increasing age and after cholecystectomy! -PEARL: measure from inner wall to inner wall Portal vein Hepatic artery Find the Gallbladder in the longest axis, follow the main lobar fissure from the neck of the gallbladder to the porta hepatis. forms the point of the exclamation mark, anterior to the portal vein. 24 6

7 Mickey Mouse sign Portal vein Hepatic artery Inferior vena cava Again, anterior to portal vein and hepatic artery. does not show flow; helps to identify the Great news perhaps finding the doesn t really matter?! What am I looking for exactly? Question Mark 7

8 Look for Acute cholecystitis by asking: Acute cholecystitis: 1) Are there gallstones present? AND 2) Is there pericholecystic fluid present? 3) Is there GB wall thickening? 4) Is there a sonographic murphy s sign? 5) +/- Is the dilated? When looking for stones, keep in mind Stones: hyperechoic, cast a shadow. Stones are often mobile; scan patients in different positions. ALWAYS convince yourself there is no stone in GB neck. Wall-echo-complex (WES): When GB is filled multiple stones or one giant stone you just see wall, then bright reflex and then shadow. Sludge: biliary sand/microlithiasis: Echoes within depending part of GB without shadowing (resettles in dependent parts > scan patients in different positions) 31 8

9 Posterior acoustic enhancement

10 37 38 WES sign Wall Echo Shadow 39 Gallbladder filled completely with stone 40 10

11 1) Is there a stone? Patient supine, stones in the neck Stones vs polyps or tumors: -stones are mobile and can be moved by changing the position of the patient, not adhered to wall. -Polyps do not shadow. Pat. rolled to left lateral decubitus, stones in body Life just got easier Brief mention: stones Dilated intrahepatic ducts Stone in Shadow cast by stone stones: round echogenic lesion with posterior shadowing. Most stones are impacted in the distal duct at the papilla. 11

12 #2) Is there pericholecystic fluid? #2) Is there pericholecystic fluid? #2) Is there pericholecystic fluid? 3) Is there GB wall thickening? PEARL: Measure anterior wall because resolution is better

13 RUQUS and GB wall thickening: 4) Is there a Sono Murphys sign? -NONSPECIFIC finding! -DDx include: CHF Renal failure Hypoalbuminemia Hepatitis Cirrhosis Pancreatitis Carcinoma. maximal abdominal tenderness from pressure of the ultrasound probe over the visualised gallbladder SMS is a sign of local inflammation around the gallbladder along with right upper quadrant pain, tenderness or mass 49 list.aspx?cat= murphys sign and sonographic.html 5) Is the dilated? <=6mm is normal Add 1 mm as normal dilatation for every decade above 60 years old dilated in pts s/p cholecystecomy Measure INNER wall to inner wall FYI: Cholangitis Fever, RUQ pain, Jaundice. ~85% of cases associated with stones. On ultrasound: Dilation of biliary tree Choledocholithiasis and possibly sludge Bile duct wall thickening Hepatic abscess with thickened wall Stone in Shadow cast by stone 51 13

14 Again, ask yourself: 1) Are there gallstones present? AND 2) Is there pericholecystic fluid present? 3) Is there GB wall thickening? 4) Is there a sonographic murphy s sign? 5) +/- Is the dilated? Take home points: Always scan through the GB in both longitudinal and transverse planes. Scan through GB neck to ensure no obstructing stone Use color Doppler to help distinguish nonvascular from vascular structures. Be aware of normal variants (folds). Measure the anterior wall of the gallbladder. Normal GB wall <4mm Normal <7mm Position for success: left lateral decubitus Can t see the GB? Ask pt to take a deep breath in Stones are mobile and shadow; polyps do not. Ultrasound findings must ALWAYS be interpreted in the context of the clinical presentation. 53 Further reading Hepatobiliary disease: a comparative evaluation by ultrasound and computed tomography, Raskin MM. Gastrointest Radiol Aug 31;3(3): Thank you! Questions? Kathleen.OBrien@kp.org, katieoinaz@gmail.com Role of ultrasonography for acute cholecystic conditions in the emergency room. Golea et al. Med Ultrason 2010 Dec;12 (4):271-9 Performance and interpretation of focused right upper quadrant ultrasound by emergency physicians Kendall et al. J Emerg Med 2001 A prospective evaluation of emergency department bedside ultrasonography for the detection of acute cholecystitis, Shane et al. 14

15 Gallbladder Portal vein QuickTime and a Animation decompressor are needed to see this picture. Hepatic artery Inferior vena cava Exclamation point sign 15