Transcript DISIDA ( TESTBOOK)

HEPATOBILIARY IMAGING
Presented by
Yang Shiow-wen
11/26/2001
Hepatobiliary Imaging
 Evaluates hepatocellular function and
patency of the biliary system
 Tracing the production and flow of bile from the
liver through the biliary system into the small
intestine
 Sequential images of the liver, biliary tree and
gut are obtained
 A "HIDA" scan or a "DISIDA" scan
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Hepatobiliary Imaging
 Performed with a variety of
compounds that share the common
imminodiacetate moiety
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Structures of IDA derivates
Blue color: A polar
component (the diacetate)
Red: A lipophilic
component
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IDA-chelated Tc-99m
 A magnification of two
imminodiacetate
compounds
 Polar components
chelated a Tc-99m
molecule
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Pathways of IDA derivates
 The lipophilic component : binding to
hepatocyte receptors for bilirubin
 Transported through the same
pathways as bilirubin, except for
conjugation
 Excretion decreased with increasing
bilirubin levels
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HIDA
 HIDA
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Little used today
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DISIDA (Disofenin)
 85% extracted by the hepatocytes
 Visualization of gallbladder and CBD
when bilirubin > 8 ng/dl
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BRIDA (Mebrofenin)
 98% extracted by the
hepatocytes (bilirubin <1.5
mg/dL)
 Visualization of gallbladder
and CBD when bilirubin > 30
ng/dl
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Higher hepatic extraction
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BRIDA (Mebrofenin)
 Rapid biliary to bowel transit time
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Taken into consideration when evaluating acute
cholecystitis
 Mebrofenin may be preferred over Disofenin in
suspected biliary atresia
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Indications
 Functional assessment of the hepatobiliary
system
 Integrity of the hepatobiliary tree
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Evaluation of suspected acute cholecystitis
Evaluation of suspected chronic biliary tract
disorders
Evaluation of common bile duct obstruction
Detection of bile extravasation
Evaluation of congenital abnormalities of the
biliary tree
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Contraindications
 Hypersensitivity to
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IDA derivative
Local anesthetics of the amide type
 With disturbances of cardiac rhythm
or conduction
 Pregnancy Category: C
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Requirements for DISIDA Scan
 Patient preparation: fasted for 2-4 hours
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Otherwise delayed or non-visualization
Fasted for > 24 hrs or on TPN, a false-positive study may
occur
 Radiotracer
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Adult
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1.5-5 mCi Tc-99m IDA compounds i.v.
3 – 10 mCi for hyperbilirubinemia
Children
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0.05 – 0.2 mCi/kg
minimum of 0.3 – 0.5 mCi
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Requirements for DISIDA Scan
Additional information
 History of previous surgeries, especially biliary and
gastrointestinal
 Time of most recent meal
 Current medications
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esp. opioid compounds
Delaying the study for 4 hr after the last dose
 Bilirubin and liver enzyme levels
 Results of ultrasound
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Requirements for DISIDA Scan

Gamma camera
A large field of view with a low energy all
purpose or high resolution collimator
 A smaller field of view with a diverging
collimator
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Requirements for DISIDA Scan
 Serial anterior views for 60 minutes
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Until activity is seen in both the gallbladder (patency of the cystic duct)
and the small bowel (patency of the common bile duct)
Every 5 minutes for 30 minutes
Once at 45 minutes
Once at 1 hour
 Right lateral views
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At 30, 60 minutes
 Oblique views
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Separate gallbladder from small bowel activity
 Delayed views
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At 2 hours, 4 hours, 6 hours or 24 hours after injection
Severely ill patient, suspected CBD obstruction, suspected biliary atresia
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Interventions
 CCK (0.01-0.02 ug/kg)
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Fasting for >24-48 hours, or on TPN
Empty the gall bladder (low resistance to bile flow state)
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Preferential gallbladder filling
Delayed biliary to bowel transit
Injection 30 min prior to the test
Administered slowly (3 – 5 min)
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Prevent biliary spasm and abdominal cramps
 Water (5-10 cc)
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Distinguish transient duodenal activity from gallbladder
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Interventions
 Morphine sulfate (0.04-0.1 mg/kg)
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When acute cholecystitis is suspected
and the GB is not seen by 60 min
& Radiotracer within the small intestine
Enhancing sphincter of Oddi tone
Increasing pressure within the CBD
 Diverting bile away from the sphincter of Oddi
& into functionally obstructed sludge filled
gallbladder
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Interventions
 Fatty meal stimulation
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Gallbladder ejection fraction measurement
 Phenobarbital
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When biliary atresia is suspected
5 mg/kg/day (orally) for 3 – 5 days prior to the
study
Enhancing the biliary excretion of the
radiotracer
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Processing
 Gallbladder ejection fraction (GBEF)
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Using the immediate pre-CCK and the post-CCK
data
Regions of interest (ROI) are drawn around the
GB and adjacent liver (background)
 Hepatic extraction fraction (HEF)
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Index of hepatocellular function
Deconvolution analysis from ROI over the liver
and heart
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Normal Study
 Immediate demonstration of hepatic parenchyma
 Prompt clearance of the blood pool within the first
5 minutes
 Biliary excretion should commence within 20
minutes (5-10 min)
 Biliary ducts would visualize followed the
gallbladder
 Gallbladder and small bowels are visualized within 1
hour
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Acute Cholecystitis
 The most common indication
 S\S
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Nausea, vomiting, fever
Right upper quadrant pain post-prandially
Mild to moderate leukocytosis
Abnormal liver function test
Pain radiates to the back (scapula)
 Obstruction of cystic duct
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By a gallstone
Inflammation, edema, gallbladder mucous, or a tumor (5%)
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Acute Cholecystitis
 DISIDA scan
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Sensitivity: 95%, specificity 93-96%
Positive predictive value: 92.1%, negative
predictive value: 99%
 Adequate filling of the gallbladder
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Acute cholecystitis is effectively excluded
 Cystic duct obstruction
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Failure to visualize the gallbladder up to 4 hours
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Acute Cholecystitis
 When acute cholecystitis is suspected
and the gallbladder is not seen within
40–60 min
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3 – 4 hr delayed images should be
obtained
Rule out chronic cholecystitis
Premedication with CCK
Morphine augmentation
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Acute Cholecystitis
 Premedication with CCK
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Same sensitivity and specificity
Disadvantages
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Not differentiated chronic cholecystitis from normal
Nausea, vomiting, exacerbation of bladder pain
Missed acute cholecystitis exhibiting delayed
gallbladder visualization
Without delayed views
 Malrotaion, enterogastric reflux, masses displacing or
inflammatory processes of the small bowel
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Acute Cholecystitis
 Ingestion of morphine sulfate
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More accurately, less complication
Differential diagnosis for non-visualization of
the gallbladder
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Relaxation of the sphincter of Oddi
Imaging is usually continued for another 30 min
Contraindications
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Absolute: Respiratory depression in non-ventilated
patients, morphine allergy
Relative: acute pancreatitis
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Acute Cholecystitis
 The hallmark of acute cholecystitis (acalculous as
well as calculous)
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Persistent gallbladder non-visualization 30 min postmorphine or on the 3 – 4 hr delayed image
 Rim sign
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A band or rim of increased activity adjacent to gallbladder
fossa
Associated with severe phlegmonous/gangrenous acute
cholecystitis, a surgical emergency
Cystic duct obstruction, acute cholecystitis
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Chronic Cholecystitis
 Ultrasound is the primary modality of
choice
 S\S
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Usually having gall stones
The cystic duct is not blocked
More chronic pain
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Common Bile Duct Obstruction
 Delayed visualization of the gall bladder
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Clinical settings associated with physiologic failure of the
gallbladder to filling
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e.g. fasting for >24 – 48 hr, severely ill or post-operative patients may
result in GB non-visualization within the first hour
A larger dose of morphine (0.1 mg/kg) decrease the false positive
rate
 Separated from acute cholecystitis using morphine or delayed
imaging
 Reduced gallbladder ejection fraction in response to CCK
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Indicative of chronic cholecystitis, gallbladder dyskinesia or the
cystic duct syndrome
Visualization of the GB after the bowel
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Common Bile Duct Obstruction
 S\S
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Hyperbilirubinemia (> 5 mg/dl)
Dilation of CBD (sonography, >3 days)
A history of pancreatitis (serum amylase)
 DISIDA scan
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High grade or a total CBD obstruction
Sensitivity: 95%
Detection immediately
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Common Bile Duct Obstruction
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Delayed biliary-to-bowel transit beyond 60 min
raises the suspicion
Activity in the small bowel seen within 60 min
does not entirely exclude partial CBD
obstruction
When neither the gallbladder nor the small bowel
are seen within 18–24 hrs
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Suspected High grade CBD obstruction
Severe hepatocellular dysfunction may appear similar
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Bile Leaks
 Most appropriate non-invasive imaging technique for
evaluation of bile leaks
 Sensitivity: 87%, Specificity: 100% (2-3 ml of labeled bile)
 Radiopharmaceutical activity
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In an extrahepatic and extraluminal location
More intense with time
 Differentiating intraluminal activity from a leak
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Standing views in addition to decubitus views
Cinematic display
3 – 4 hrs delayed imaging
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Biliary Atresia
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Excluded by demonstrating transit of
radiotracer into the bowel
Failure of tracer to enter the gut
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Hepatocellular disease
Immature intrahepatic transport mechanisms
Biliary atresia
CBD obstruction
Urinary excretion of the tracer (especially in
diaper) may be confused with bowel activity
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Duodenogastric Bile Reflux
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Highly correlated with bile gastritis
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Cause of epigastric discomfort
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False Positive Study
 Gallbladder non-visualization in the absence of acute
cholecystitis
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Insufficient fasting (<2 – 4 hr)
Prolonged fasting (>24 – 48 hr), especially total parenteral
nutrition (despite CCK pre-treatment and Morphine augmentation)
Severe hepatocellular disease
High grade common bile duct obstruction
Severe intercurrent illness (despite CCK pre-treatment and
Morphine augmentation)
Pancreatitis (rare)
Rapid biliary-to-bowel transit (insufficient tracer activity
remaining in the liver for delayed imaging)
Severe chronic cholecystitis
Previous cholecystectomy
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False Negative Study
 Gallbladder visualization in the presence of acute
cholecystitis
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Bowel loop simulating gallbladder (drinking water may help
to clarify anatomy)
Acute acalculous cholecystitis
The presence of the "dilated cystic duct" sign simulating
GB. (Morphine should not be given)
Bile leak due to GB perforation
Congenital anomalies simulating gallbladder
Activity in the kidneys simulating gallbladder or small
bowel (may be clarified by a lateral image)
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Reflux into Stomach
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Radioactivity in Left Subphrenic Space-I
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Bile Leak Post-cholecystectomy-II
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References
 http://www.vh.org/Providers/Lectures/IROCH/BiliaryNucs/BiliaryN
ucs.html (Virtual Hospital)
 http://www.cancerboard.ab.ca/about/ercdocs/diiso.html
 http://www.nuclearonline.org/PI/Bracco%20mebrofenin%20d
oc.pdf
 http://www.snm.org/pdf/hb2.pdf
 http://www.vh.org/Providers/Textbooks/ElectricGiNucs/Text
/Hepatobiliary.html
 Chapter 38, Hepatobiliary Imaging, Darlene Fink-Bennett, P759-770
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The End
Thank for Your Attention !
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