Preparation Ultrasound Imaging the Jaundiced · PDF fileCholedocholithiasis Gallbladder...

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Transcript of Preparation Ultrasound Imaging the Jaundiced · PDF fileCholedocholithiasis Gallbladder...

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    UltrasoundImaging the Jaundiced dog

    ROBERT H. WRIGLEYROBERT H. WRIGLEY

    Professor Professor Veterinary Diagnostic ImagingVeterinary Diagnostic ImagingUniversityUniversity of Sydneyof Sydney

    Veterinary Teaching HospitalVeterinary Teaching HospitalProfessor Emeritus Colorado State Professor Emeritus Colorado State

    UniversityUniversity

    Preparation

    Withhold food to allow stomach to empty

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    Normal GallbadderBiliary Sediment/Sludge

    Amount within the GB is variable Seen in healthy, non fasting dogs. Considered an incidental finding Seen with biliary stasis from fasting or

    illness Usually does not shadow Sludge balls

    Round, mobile, nonshadowing structures Uncertain cause and significance

    Courtesy Dr H Thode

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    Cystic Mucinous Hypertrophy or Hyperplasia of the Gall Bladder

    Not associated with obstruction of CD Not associated with any clinical findings Considered an incidental finding Histologically

    No evidence of inflammation Serosal, muscular, and vascular structures appear

    intact and normal Mucosal surface irregular; polypoid cystic lining

    Ultrasound Thickened, irregular GB wall Biliary sludge usually observed

    CBC, SADP, U/A

    PCV < 15Nucleated RBCs

    Bilirubinuria

    PCV > 20Abnormal liver enzymes

    Hepatic disease Post Hepatic Biliary DiseaseHemolytic Disease

    Clinical Icterus

    Courtesy Dr H Thode, CSU

    HepatitisHepatitisToxinsToxinsCirrhosisCirrhosisNeoplasiaNeoplasia

    Normal Anatomy Echogenicity comparisons

    Renal Medulla < Renal Cortex < Liver < Spleen < Renal PelvisMy Cat Loves Sunny Places

    Blacker Whiter

    Hypoechoic HyperechoicTissue Tissue

    Least Echogenic Most EchogenicTissue Tissue

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    Biopsy - Cirrhosis

    Extrahepatic Biliary Tract Disease

    Pancreatic diseases Cholelithiasis/choledocholithiasis Acute Cholecystitis Chronic cholecystitis Gallbladder Mucocele Trauma, rupture

    Anatomy Bile produced by

    hepatocytes -> bile canaliculi -> interlobular ducts -> lobar ducts -> hepatic ducts

    Cystic duct (from Gall Bladder) joins with hepatic ducts to form Bile Duct (CBD)

    CBD enters dorsal or mesenteric wall of duodenum -> major duodenal papilla Wrigley RH, Renter RE. Wrigley RH, Renter RE. PercutaneousPercutaneous cholecystographycholecystography

    in normal dogs. in normal dogs. Vet Vet RadRad, 1982; 23: 239, 1982; 23: 239--242.242.

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    Clinical Signs of ExtrahepaticBiliary Tract Obstruction (EHBO)

    Nonspecific Mimic other abdominal disorders May wax/wane for several weeks prior to

    presentation Most patients not likely to be examined

    until clinical signs of icterus develop May see acholic feces

    Diagnostic Evaluation Animals may not demonstrate clinical

    signs or hematologic abnls for weeks to months after the obstruction

    CBD obstruction Increased total serum bilirubin (>90%

    conjugated) Bilirubinuria

    renal excretion becomes important for elimination of the pigment

    may precede the development of jaundice

    Experimental Bile Duct Ligation in the Dog

    CBD surgically ligated in 5 nl adult dogs US exams performed pre-op and at 24

    hour intervals post-op Sequence of biliary system dilation was

    from CBD to peripheral intrahepatic ducts GB, cystic duct, and CBD enlargement

    evident in 24 48 hours Peripheral bile duct dilation recognized by

    5 7 days after obstructionNyland TG, Gillett NA. Nyland TG, Gillett NA. SonographicSonographic evaluation of experimental bile duct ligation evaluation of experimental bile duct ligation in the dog. in the dog. Vet Vet RadRad, 1982; 23: 252, 1982; 23: 252--260.260.

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    Pancreatic Diseases Most common cause of EHBO in dogs Scar tissue can form in/around CBD Duct can be compressed by

    Inflamed pancreatic tissue Fibrotic pancreatic tissue Pancreatic neoplasia Pancreatic abcess/cyst (rare)

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    Cholelithiasis/Choledocholithiasis

    Account for < 1% of patients with liver dz Believed to be typically clinically silent

    Common, incidental postmortem findings Up to 75% of reported cases of choleliths

    have been diagnosed at necropsy with no reported associated clinical signs

    Clinical signs associated with cholelithiasisthought to be more commonly related to cholecystitis

    Choledocholithiasis

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    Acute Cholecystitis May have a variety of sonographic

    appearances GB wall thickening usually a consistent

    finding Pain may be detected in region of the GB

    during scanning Emphysematous cholecystitis

    Gas formation in wall/lumen of GB Usually combination of GB wall ischemia and

    proliferation of gas-forming bacteria

    Chronic Cholecystitis

    Usually presents in a less acute form than acute cholecystitis

    Can see GB wall thickening due to inflammation and fibrosis

    Fibrosis/inflammation may prevent even normal distention of the GB

    Mineralization of the GB wall may occur with chronic inflammation

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    Liver disease is common in cats Cholangitis/cholangiohepatitis: 20-30% Ascending bacterial infection Biopsy and culture needed for diagnosis Specific long-term antibiotic therapyPercutaneous ultrasound-guided

    cholecystocentesis - Considered routine in humans

    Percutaneous Ultrasound-guided Cholecystocentesis in Healthy Cats

    Savary- Bataille et al. JVIM 2003 17: 298-303

    Courtsey Dr Quimby CSU

    Methods - PUC Ketamine/valium sedation 22 gauge/1.5 inch with 12 ml syringe Right transhepatic approach (1 cat) Right ventral direct puncture (11 cats)

    Right transhepatic approach immediate mild effusion, hemorrhagic bile (1 cat)

    Right ventral direct approach no complications (11 cats)

    1.8ml +/- 0.8ml (range 0.9 3ml)

    Results - PUC

    Results

    Right transhepatic approach immediate mild effusion, hemorrhagic bile (1 cat)

    Right ventral direct approach no complications (11 cats)

    1.8ml +/- 0.8ml (range 0.9 3ml)

    Direct proportional relationship between weight and volume of bile.

    Results

    4 cats had mild transient hyporexia 4 cats had mild abdominal discomfort No U/S changes for direct approach

    Necropsy no abnormalities noted Cytology 11 cats - just bile Cultures

    No growth One contaminant

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    Wrigley RH, Renter RE. Percutaneous cholecystography in normal dogs. Vet Rad, 1982; 23: 239-242.

    Finish by emptying the gallbladder

    Fast for additional 12 hours

    Choledocholithiasis

    Gallbladder Mucocele

    An abnormal accumulation of mucus distending the gallbladder

    Etiology is uncertain ? Bile stasis ? Mucinous hyperplasia of GB mucosa ? Inflammation ? Biliary sludge a predisposing factor ? Altered contractility of the GB wall ? Combination of factors

    Gelatinous bile may extend into CD and/or CBD and cause obstruction

    Gallbladder Mucocele Tendency to affect smaller dogs Cocker Spaniels may be predisposed More common in older dogs Clinical signs nonspecific Usually have clinocopathologic evidence of

    hepatobiliary disease 50 60% incidence of GB rupture

    Poor prognosis Cholecystectomy (emergency if GB wall rupture is

    suspected)

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    Bile Patterns with Mucoceles Besso JG, Wrigley RH, et al.

    Ultrasonographic appearance and clinical findings in 14 dogs with gallbladder mucocele. Vet Rad & US, 2000; 41: 261-271.

    Pike FS, et al. Gallbladder mucocele in dogs: 30 cases (2000-2002). JAVMA, 2004; 224: 1615-1622.

    Worley DR, et al. Surgical management of gallbladder mucoceles in dogs: 22 cases (1999-2003). JAVMA, 2004; 225: 1418-1422.

    References Besso JG, Wrigley RH, et al. Ultrasonographic appearance and clinical findings in 14 dogs with

    gallbladder mucocele. Vet Rad & US, 2000; 41: 261-271. Center SA. Diseases of the biliary tree. In: Guilford WG, et al, eds. Small Animal

    Gastroenterology. Philadelphia: WB Saunders,1996: 860-861, 865. Mehler SJ, Bennett RA. Canine extrahepatic biliary tract disease and surgery. Compendium,

    2006; 28: 302-314. Newell SM, et al. Gallbladder mucocele causing biliary obstruction in two dogs: ultrasonographic,

    scintigraphic, and pathological findings. Jnl AAHA, 1995; 31: 467-472. Nyland TG, Gillett NA. Sonographic evaluation of experimental bile duct ligation in the dog. Vet

    Rad, 1982; 23: 252-260. Nyland TG, Mattoon JS, et al. Liver. In: Nyland TG, Mattoon JS, eds. Small Animal Diagnostic

    Ultrasound. Philadelphia: WB Saunders, 2002: 113-117. Partington BP, Biller DS. Liver. In: Green RW, ed. Small Animal Ultrasound. Philadelphia:

    Lippincott-Raven, 1996: 119-124. Pike FS, et al. Gallbladder mucocele in dogs: 30 cases (2000-2002). JAVMA, 2004; 224: 1615-

    1622. Rivers BJ, et al. Acalculus cholecystitis in four canine cases: ultrasonographic findings and use of

    ultrasonographic-guided percutaneous cholecystocentesis in diagnosis. Jnl AAHA, 1997; 33: 207-214.

    Worley DR, et al. Surgical management of gallbladder mucoceles in dogs: 22 cases (1999-2003). JAVMA, 2004; 225: 1418-1422.

    Wrigley RH, Renter RE. Percutaneous cholecystography in normal dogs. Vet Rad, 1982; 23: 239-242.