Gallstones & Pancreatitis Lecture Notes PDF

# Gallstones - Joseph W. Owen, MD - *By wisam neriman* ## RUQ U/S: Introduction - Quick, safe modality - Expedite patient care - Has many applications, including evaluation of: - RUQ/epigastric pain - Jaundice - Ascites ## Anatomy: Key Concepts - CBD + portal v + hepatic art. = portal...

# Gallstones - Joseph W. Owen, MD - *By wisam neriman* ## RUQ U/S: Introduction - Quick, safe modality - Expedite patient care - Has many applications, including evaluation of: - RUQ/epigastric pain - Jaundice - Ascites ## Anatomy: Key Concepts - CBD + portal v + hepatic art. = portal triad - Common bile duct (CBD) runs _anterior_ to the portal v prior to entering duodenum - Significant anatomic variation in position, shape, size of GB ## Technique - Ideally, pt is NPO (nil per os) - to reduce bowel gas - Probe: curvilinear or phased array - Low frequency (3-5 MHz) - Patient position: supine, left lat decub (left lateral decubitus), others ## Normal GB - Two images are shown, one taken while fasting and one taken post-prandially. - The images show a normal gallbladder (GB) on an ultrasound. - An arrow points at the GB in each image. ## Step 2: Carefully Examine GB - Scan GB in multiple longitudinal & transverse planes - Look for: - Gallstones - Wall thickness - Pericholecystic fluid (PCF) ## Step 2: Carefully Examine GB: Pericholecystic Fluid (PCF) - Fluid (anechoic) around GB. - False positive: ascites. - Image shows an ultrasound of the GB with arrows indicating the PCF. ## Step 2: Carefully Examine GB: Wall Thickness - Normal: up to 4 mm. - May be thickened with: - Acute cholecystitis - CHF (congestive heart failure) - Low protein states/ESLD (end-stage liver disease) - Carcinoma of GB - The image is an ultrasound of the GB with an arrow showing the thickened wall. ## Step 3: Assess for Sonographic Murphy's Sign - Place U/S probe directly over GB fundus - Compress GB - If pt has pain during inspiration (or if they stop inspiring) during GB compression --> positive - Intuitively seems more sens/spec (sensitive and specific) than traditional Murphy's sign. - Little data however. ## Step 4: Find the Portal Triad - Triad = PV (portal vein) + CBD (common bile duct) + hep art (hepatic artery) - Start w/ long view of PV (easiest to find first) - Probe in RUQ with probe marker towards R axilla (right axilla) - Note the _hyperechoic_ vessel walls - Courses towards porta hepatis ## Step 4: Find the Portal Triad: Measure the CBD - Normal diameter of CBD < 5 mm - Upper limit of nl (normal) increases with age - May be nearly 1 cm after chole (cholecystectomy) - Enlarged CBD and RUQ pain suggests choledocholithiasis. - Image shows an ultrasound of the liver. Arrows indicate the GB and CBD. ## GB: Longitudinal/Oblique View - Image shows an ultrasound of the liver. Arrows indicate the liver, GB, & PV. ## Gallstones - Best seen on ultrasound or MRI - Pigment stones are evident on CT - Cystic duct obstruction may cause biliary colic or cholecystitis - Common bile duct obstruction may cause ascending cholangitis or acute pancreatitis ## Gallstones - Ultrasound - Two ultrasound images of the GB are shown. Each image has arrows highlighting the hyperechoic gallstone with an acoustic shadow. ## Gallstones - MR - Two MRI images of the GB are shown. ## Gallstones - CT - Two CT images of the GB are shown with arrows highlighting the pigmented stones. - Cholesterol stones are not typically seen on CT. ## Acute cholecystitis - US - Two ultrasound images are shown of a GB with acute cholecystitis. - The images show a thickened wall and gallstones. - The key findings are: - Gallstones or sludge - Wall > 3 mm - Pericholecystic fluid - Positive sonographic Murphy's sign. ## Pearls, Pitfalls, and Variants - **Septate GB -** An ultrasound image is shown. - **Phrygian Cap** - An ultrasound image is shown. ## Pearls, Pitfalls, and Variants - All shadows do not equal gallstones! - Bowel gas, edge artifact, spiral valves - GB + gallstones ≠ cholecystitis. - Remember, gallstones are common. - Present in ~ 20% of pts > 50 yo. - An ultrasound image of the GB with gallstones is shown. ## Acute cholecystitis – MR or CT - Two images are shown, one MRI and one CT. The images show signs of acute cholecystitis, including stranding, thickened wall, and gallstones. ## Choledocholithiasis - Images show: - CT of the liver with arrows pointing to a dilated bile duct. - Ultrasound of the liver with arrows pointing to a dilated bile duct. - MRI of the liver with arrows pointing to a gallstone. - ERCP of the bile duct with arrows pointing to a gallstone. - Lab Values (all elevated): - Alk Phos (alkaline phosphatase) - GGT (gamma-glutamyltransferase) - Direct Bilirubin - Sequela (consequence): - Can cause acute pancreatitis and cholangitis ## Choledocholithiasis can result in... - **Ascending Cholangitis** - Fever, jaundice, and right upper quadrant pain - Elevated alkaline phosphatase, and/or elevated conjugated bilirubin. - **Acute Pancreatitis** - Epigastric Pain - Elevated lipase - Peripancreatic stranding on CT or MRI # Pancreatitis - Joseph W. Owen, MD ## Pancreatitis - Acute pancreatitis presents with epigastric pain, elevated lipase and peripancreatic stranding. - Necrotizing pancreatitis results in destruction of the parenchyma and possible vascular injury. - Chronic pancreatitis is from repeated injury resulting in calcifications and duct irregularity. ## 3 Radiologic Manifestations - Uncomplicated acute pancreatitis - Necrotizing pancreatitis - Chronic pancreatitis - A CT image of the abdomen is on the right. ## Pancreatitis - An axial CT image of the pancreas is on the left. Arrows point to areas of stranding. - On the right is a normal pancreas. - The images are labelled "Uncomplicated acute pancreatitis" ## Pancreatitis - Image shows an axial CT of the pancreas with arrows indicating areas of irregular duct dilation and calcifications. - The image is labelled "Chronic pancreatitis". - The key features are: - Chronic/ recurrent epigastric pain - Normal lipase - Calcification - Duct dilation - Atrophy ## Pancreatitis, Necrotizing Pancreatitis - An axial CT image of the abdomen is shown. Arrows indicate walled off necrosis. - The key findings are: - Peripancreatic stranding - Pancreatic necrosis - Peripancreatic collections - Walled-off necrosis # Cirrhosis - Joseph W. Owen, MD ## Cirrhosis - Hepatic fibrosis - Surface nodularity - Heterogeneous liver parenchyma - Portal hypertension - Splenomegaly - Varices - Ascites - Hepatocellular carcinoma - An ultrasound image of the liver with ascites is shown. ## Ultrasound of the Liver - Three diagrams are shown, labelled: - *Diffuse Steatosis* - *Coarse Texture* - *Nodular surface* - Echogenicity – normal or increased - Echotexture – homogenous or coarse - Liver Surface – smooth or nodular ## Learning Objectives - Recognize and describe increased echogenicity of the liver associated with hepatic steatosis - Recognize and describe surface nodularity and coarsened hepatic echotexture associated with hepatic cirrhosis ## Hepatic Steatosis - Accumulation of lipid in the hepatocytes - Most commonly detected in Non-alcoholic fatty liver disease and Alcohol liver disease - Detected as increase echogencity on ultrasound - Loss of distinct periportal fat - Increased echogencitiy compared to kidney - Two diagrams are shown, one labelled "Periportal fat" and one labelled "Loss of Periportal fat", highlighting the loss of fat in hepatic steatosis. ## Smooth vs. Nodular Liver Surface - Four ultrasound images of the liver are shown in a 2x2 arrangement. - The top pair of images are labelled "Smooth" and "Nodular" - The bottom pair of images are labelled "Smooth" and "Nodular" - The images exemplify a distinction in liver morphology between smooth and nodular liver surfaces. ## Smooth vs. Nodular Liver Surface - Two ultrasound images of the liver are shown, again exemplifying the distinction between smooth and nodular liver surfaces. - One image is labelled "Smooth", the other "Nodular." - Can be easier to tell when there is ascites. ## Similar Echogenicity of Liver & Kidney vs. Increased Echogenicity - Two ultrasound images are shown. - The left image is labelled "Liver and Kidney have similar echogenicity", The right image is labelled "Liver is markedly hyperechoic to Kidney". - The images exemplify the distinction between a normal liver and a liver with steatosis. ## Cirrhosis - Three MRI images are shown, labelled "Heterogeneity", "Ascites", and "Splenomegaly". Arrows point to the key features of cirrhosis in each image, demonstrating: - Surface nodularity - Heterogeneity - Ascites - Splenomegaly ## Portal Hypertension - Four CT images of the abdomen are shown. Arrows point to the key features of portal hypertension in each image, demonstrating: - Pleural effusion - Ascites - Splenomegaly - Paraesophageal varices ## Cirrhosis - Hepatic fibrosis - nodularity and heterogeneous liver parenchcyma - Portal hypertension - splenomegaly, ascites and varices - Hepatocellular carcinoma - arterial enhancement, washout, and pseudocapsule ## Hepatocellular Carcinoma - Four MRI images of the liver are shown, demonstrating the features of hepatocellular carcinoma: - Arterial enhancement - Washout - Pseudocapsule ## Hepatic Metastasis - Two MRI images of the liver are shown, labelled "Hypovascular metastasis" and "Hypervascular metastasis". - The features of hepatic metastasis include: - Wide variety of appearances - Hypovascular - Hypervascular - Mucinous - Necrotic - Usually multifocal - Commonly from GI tumors - Best detected with MRI ## Most common site of metastatic disease - Portal Vein – Hematogenous spread of metastasis from the GI tract - Hepatic Artery – Hematogenous spread of metastasis from systemic circulation - Fenestrated endothelium of the vessels permits deposition in the liver ## Hepatic metastasis - Wide variety of appearances based on primary tumor type - Multiphase imaging with CT or MRI will increase sensitivity - MRI is the most sensitive and specific modality for detecting metastases ## Hepatic steatosis can hide metastasis - A CT image of the abdomen is shown on the left. An arrow indicates a vague hypodensity that could be a metastasis. - An MRI image of the abdomen is shown on the right. Several arrows indicate multiple metastases. - The image is labelled: - *CT demonstrating 1 or 2 vague hypodensities* - *MRI demonstrating over 20 metastases* ## Gallstone with Acoustic Shadow - An ultrasound image of the GB is shown. Arrows point to the gallstones. - Gallstones create acoustic shadows. ## GB Polyp - An ultrasound image of the GB showing a polyp is shown. ## Gallstones, Ultrasound - Hyperechoic - Look for acoustic shadow - Dependent - Move w/ gravity - May have similar appearance to polyps, malignant masses ## Portal Vein - Ultrasound image of the liver showing the portal vein is shown. ## Gallstone - An ultrasound image of the GB with a gallstone is shown. ## Sonographic Characteristics of Gallstones - Very echogenic - Create acoustic shadows (proportionate w/ size). - Dependent - Typically are mobile. - Except if impacted. ## Dilated Common Bile Duct - An ultrasound image of the liver showing a dilated CBD is shown. Arrows indicate the CBD and PV. ## Mickey Mouse Sign - An ultrasound image of the liver is shown. Arrows point to the CBD, HA (hepatic artery), PV, & IVC. - The image is labelled "Mickey Mouse Sign". A Mickey Mouse cartoon is shown in the top-right corner of the image. ## Pathology: Cholecystitis - In the acutely ill pt with RUQ pain, dx of acute cholecystitis is based on: - Stones/sludge - GB wall thickening - Pericholecystic fluid (PCF) - Sonographic Murphy's sign - Likelihood of dx increases w/ each + finding. ## Pathology: Jaundice - Wide Ddx (differential diagnosis): Hepatitis, malignancy,choledocholithiasis. - Look for evidence of biliary obstruction: - Measure CBD - Examine GB for stones. - An ultrasound image of the liver showing a dilated CBD is shown. An arrow points to the CBD. ## Pathology: Porcelain GB - GB with marked acoustic shadowing - Associated w/ GB adenocarcinoma - Two images are shown. The left image is an ultrasound image of the GB, and the right image is a radiograph. Arrows point to the GB in each image. ## Pearls, Pitfalls, and Variants: Hepatic Cyst - Sharp margins. - Anechoic. - Posterior acoustic enhancement. - An ultrasound image of the liver showing a cyst is shown. ## Pathology: Jaundice - Wide Ddx: Hepatitis, malignancy, choledocholithiasis - Look for evidence of biliary obstruction: - Measure CBD - Examine GB for stones. - An ultrasound image of the liver showing a dilated CBD is shown. An arrow points to the CBD. ## Cholecystitis - An ultrasound image of the GB showing signs of cholecystitis, including thickened walls, gallstones, and hyperechoic fluid around the GB is shown. ## Pearls, Pitfalls, and Variants: Hepatic Tumors/Metastases - An ultrasound image of the liver is shown, with a red circle drawn around a possible tumor. - The image is labelled: "Hepatic Tumors/Metastases".