IMAGING OF HEPATOBILIARY AND PANCREATIC DISEASES

Objectives

State the imaging modalities available to assess the hepatobiliary and pancreatic diseases. Discuss the imaging modalities of choice in different pathological conditions Correlate the imaging with pathology Identify the imaging features of common pathological conditions

Recall – Anatomy

Imaging Methods

Ultrasound CT Nuclear Medicine MRI Contrast studies Plain x-ray

Presentations of patients for imaging

RHC or epigastric pain Abnormal physical examination Jaundice Abnormal lab investigations Infections Staging of tumours Trauma

RHC Pain

Common problem Cholelithiasis - Gall stones

Imaging of choice

US

Why?

Helpful to assess any inflammatory changes or biliary dilatation

Cost

Availability

Other modalities used – HIDA, CT, MRI

USS – Gallstones

Cholecystitis

USCTMRISCINTIGRAPHY

Sonographic Murphy’s sign

Focal tenderness corresponding to the GB

Helps physicians to separate - Acute cholecystitis from gallstones alone.

Complications of Gall stones

1. Cystic duct obstruction2. CBD obstruction3. Pancreatic duct obstruction

Obstructed duct due to distal calculus

CBD

PV

*Note dilated bile ducts

Others

Emphysematous cholecystitis Acalculus cholecysytitis Gall stone ilius

Emphysematous cholecysytitis

Acalculus cholecysytitis

Gall stone ileus

Small Bowel Obstruction at ileocaecal valve due to migration of gallstones that erode into duodenum from GB.

RUQ PAIN Imaging

Ultrasound – 1st CT / HIDA – 2nd ERCP / MRCP-- 3rd

JAUNDICE

Jaundice is the yellow colouration of skin and mucous membranes due to accumulation of bile pigments in blood and their deposition in body tissues

Normal Serum Bilirubin (SB) is 0.3 to 1.0 mg% Jaundice is increased levels of SB > 1.0 mg%

Causes

Over production of Bilirubin (Hemolytic) -*Pre-hepatic From haemolysis of RBC / RBC precusors

Impaired hepatic function (Hepatitic) -*Hepatic Hepatocellular dysfunction in handling bilirubin

Obstruction to bile flow (Obstructive) -*Post-hepatic Intrahepatic cholestasis Extrahepatic Obstruction (Surgical Jaundice)

Imaging

Plays a vital role in establishing the underlying aetiology and planning management. Image-guided interventional techniques are used for therapeutic procedures and for diagnostic

purposes

An Approach to Jaundice

Is it isolated elevation of serum bilirubin? Is it ↑unconjugated or conjugated fraction?

Is it accompanied by other liver test abnormalities? Is hepatocellular or cholestatic?

If cholestatic, is it intra- or extrahepatic? Answered with ,

o History and physical examinationo Interpretation of laboratory tests & radiological tests and procedures

Jaundice – Viral Hepatitis

Imaging – Limited value Acute – usually normal Helps to exclude obstruction Chronic – increased malignancy risk

Hepatitis

Common causes of Post Hepatic (Obstructive) Jaundice

Gallstone Carcinoma of head of pancreas/ ampulla / bile duct Iatrogenic strictures of biliary tree. Perihepatic lymphadenopathy

Evaluation of Obstructive Jaundice

What imaging we need?

Ultrasonography – 1st test ordered. Ultrasonography and CT scanning are useful in distinguishing an obstructing lesion from

hepatocellular Ultrasonography is the most sensitive imaging technique for detecting biliary stones. CT scanning can provide more information about liver and pancreatic parenchymal disease.

MRCP – Most useful for duct stone / Hilar obstruction PTC – Extrahepatic obstr. – drainage ERCP – Distal biliary obstruction Bx. & Rx. Endoscopic US

Obstructive Jaundice- USS

Localize site of obstruction Indicates presence of ( Cause) Calculi, Dilated biliary tract Mass lesions Low cost No radiation Non – invasive

Extra- hepatic bile duct dilatation

Cholangiocarcinoma – USS

Cholangiocarcinoma

Adenocarcinoma that arises from bile duct epithelium

CT

More likely to identify site and nature of obstruction More costly More radiation For diagnosis and for staging in malignant biliary obstruction

CT - Hydatid cyst

CT -Ampullary Carcinoma

Magnetic Resonance Imaging (MRI)

Demonstrate both the site and cause of obstruction

MRI Abdomen

Magnetic Resonance Cholangio-Pancreatography (MRCP)

ERCP (Endoscopic Retrograde Cholangio- Pancreatography)

Diagnostic Therapeutic

ERCP

Irregular dilation of intrahepatic and extrahepatic ducts.

PTC

Diagnostic Therapeutic- Drainage/ Stenting

Periampullary growth (PTC)

T tube cholangiogram

Pancreatic Cancer/Obstructive Jaundice

Altered Lab Ix

Bilirubin Serum Amylase

Pancreatitis

Biliary calculi-obstruction Alcohol- chemical toxicity

Complications of Pancreatitis

Pseudocyst Infection Hemorrhage Pancreatic insufficiency

Pancreatic Abscess

Chronic Pancreatitis

Physical examination findings

Enlarged liver Tender Liver Enlarged spleen Ascites - distention

Hepatoma

Palpable Liver Metastasis

Hepatic Abscess