Imaging of Gallbladder Disease

Transcription

1 Acta Radiológica Portuguesa, Vol.XXIII, nº 90, pág , Abr.-Jun., 2011 Imaging of Gallbladder Disease Jade Wong Professor of Radiology University of Maryland School of Medicine Visiting lecturer Armed Forces Institute of Pathology Outline Gall stones Acute and chronic cholecystitis and variants Polyps and polypoidal lesions Malignancy Gall bladder wall thickening Gall stones Ultrasonography Accuracy 96% Echogenic Shadow (clean) Discrete Confluent Wall echo shadow Intraluminal, dependent and mobile 20 million adults Gall Stones 12% of US population 80% asymptomatic 20% biliary colic 700,000 cholecystectomies 3000 deaths Variable Isodense: high cholesterol content Hyperdense/calcifi cation Hypodense, gas Gall stones CT Lamellation and fissuring Gall stones Risk factors: Sex, age, obesity, hyperalimentation, ileal disease, ethnicity, oral contraceptive steroids and conjugated estrogens Hepatic hypersecretion of biliary cholesterol with altered secretion rates of biliary bile salts or phospholipids Cholesterol, bilirubin, calcium salts, protein > 75% principally cholesterol (F>M) 10% pure cholesterol 10-25% pigment Gall stones MR Little or no signal on T2 Pigment stones: T 1 bright, T2 dark Cholesterol stones: T1 dark T2 dark ARP 115

2 Acute cholecystitis 3-9% admissions for acute pain Clinical diagnosis needs to be confirmed with imaging US fast, accurate, inexpensive, accessible, alternative diagnosis CT less sensitive for stones, second choice HIDA more sensitive and specific but takes longer, radiation MRCP for CBD stones Trowbridge RL, et al. Does this patient have acute cholecystitis? JAMA. 2003;289(1):80-86 Acute calculous cholecystitis CT Less sensitive (75%) for stones Major criteria: calculi, mural thickening, pericholecystic fluid, subserosal edema Minor criteria: gallbladder distension, sludge Sensitivity 91.7% Specificity 99.1% Accuracy 94.3% Acute cholecystitis % secondary to obstructing gall stones Inflammation, infection and necrosis 5% acute acalculous cholecystitis Rubens DJ. Ultrasound Imaging of the biliary tract. Rad Clin N Am. 2007;2(3): Acute cholecystitis MRI/MRCP Equal performance Gall bladder distension, wall thickening with increased T2 SI Pericholecystic fluid Fluid around liver (C sign) Transient increased enhancement of the adjacent liver parenchyma Acute cholecystitis: features Cholelithiasis Distension: obstructing stone Inflammation Wall thickening > 3-4 mm Pericholecystic fluid Hyperemia GB wall Tenderness Murphy sign Fat stranding Hyperemic liver Complicated acute cholecystitis Ischemia and necrosis Gangrene (NB: pain more diffuse, negative Murphy sign) Perforation Hemorrhage Emphysematous cholecystitis Acute calculous cholecystitis Ultrasound Sensitivity 80% to 100% Specificity 60% to 100% Gallstones Positive sonographic Murphy sign Gallbladder wall thickening PPV 94% R alls PW et al. Real time sonography in suspected acute cholecystitis. Radiology 1985; 155: Smith EA et al. Cross-Sectional Imagin g of Acute and Chronic Gallbladder Inflam matory Disease. AJR 2009: 192: Gangrene 20% Asymmetry or discontinuity of wall Intraluminal membranes Intramural/intraluminal gas Pericholecystic abscess Lack of enhancement Immediate surgery Bennett GL, et al. CT findings in acute gangrenous cholecystitis. AJR 2002; 178: ARP

3 Empyema Gall bladder distended with pus Diabetic Higher attenuation on CT Drainage Emphysematous cholecystitis <1% 40 % have diabetes Men > women Gas forming infection Increased risk of gangrene and perforation, high mortality Dirty versus clean shadow not always helpful Perforation Up to 10% Mortality 20% Acute leads to peritonitis (10%) Subacute leads to contained abscess (60%) Chronic leads to fistula (30%) Hanbidge AE, et al. Imaging evaluation for acute pain in the right upper quadrant. RadioGraphics 2004;24: Porcelain gall bladder Diffuse thick calcification Rare Chronic cholecystitis causes wall calcification Reported to be associated with cancer in 12-61% Gall stone ileus Erosion of a stone into the gut with subsequent obstruction Stone > 2 cm Occurs at duodenum and becomes lodged at sites of narrowing e.g IC valve, Pneumobilia and bowel obstruction with a calculus Porcelain gall bladder Association with gall bladder carcinoma weak 25,900 gallbladder specimens at Massachusetts General Hospital 150 gallbladder cancer 44 calcified gallbladders Cancer in 7% selective mucosal wall calcification None with diffuse intramural calcification Risk associated with focal calcification rather than diffuse intramural calcification Surgery 2001;129: Hemorrhagic cholecystitis Atherosclerosis predisposes to mucosal ulceration and necrosis and hemorrhage Colic, jaundice and melena High mortality Intraluminal echoes and clots High density on CT Choledocholithiasis 10-20% have common duct stones Dilated bile ducts Sensitivity 75%; US limited for distal CBD MRCP/CT ARP 117

4 Mirizzi Impacted stone in neck or cystic duct Obstructs CHD Type 1 simple Type 2 erosion of wall of CHD fistula MRCP may be useful preoperatively to show level of obstruction Acalculous cholecystitis Ultrasound less specific, higher complication rate, mortality up to 60% Distension, sludge, wall thickening, hypoechoic regions in wall, pericholecystic fluid, increased echogenicity within the gallbladder from hemorrhage, pus, intraluminal membranes Scintigraphy with CCK false positive Diagnostic and therapeutic cholecystostomy Pitfalls Murphy sign negative: gangrene, opioids, state of consciousness, steroids Murphy sign positive: liver, bowel, kidney, other Wall thickening from multitude of causes Non visualized gall bladder van Breda Vr iesman AC, et al. Diffuse gallblad der wal l thickening: differential diagnosis. AJR 200 7; 188: Xanthogranulomatous cholecystitis Chronic inflammation with nodules formed of foamy histiocytes Pain, vomiting, leucocytosis and positive Murphy Women s More complications (32% abscess, perforation, fistula, local extension) Difficult laparoscopic surgery Parra JA, et al. Xanthogranulomatous Cholecysti tis Clinical, Sono graphic, and CT Findings in 26 Patients. AJR 2000; 174: Chronic cholecystitis Repeated bouts of acute inflammation May coexist with acute cholecystitis Wall thickening Xanthogranulomatous cholecystitis Tender palpable mass Marked gallbladder wall thickening with hypoechoic/hypoattenuating nodules Gall stones Disruption of mucosa Pericholecystic fluid May mimic carcinoma at imaging Extends to liver Parra JA, et al. Xanthogranulomatous Cholecysti tis Clinical, Sono graphic, and CT Findings in 26 Patients. AJR 2000; 174: Levy RadioG raphics 2002; 22: Acalculous cholecystitis Signs of cholecystitis without stones Sepsis in ill patients, ventilated, intensive care, diabetes, post surgery and trauma Diminished gallbladder emptying Decreased blood flow in the cystic artery because of obstruction, hypotension, or embolization Bacterial infection Ischemic GB, gangrene and perforation Xanthogranulomatous cholecystitis MRI High T2 nodules Preservation of linear mucosal enhancement 118 ARP

5 Polypoidal gall bladder lesions 3-5 % Adenomyomatous hyperplasia Hyperplastic cholecystosis includes cholesterolosis and adenomyomatosis Cholesterolosis deposition of triglycerides and cholesterol esters within the lamina propria characteristic gross appearance of strawberry gallbladder Non neoplastic 95% Cholesterol 60% Adenomyomatosis 25% (10-20mm) Inflammatory 10% (<10mm) Heterotopia Adenomyomatosis Proliferation of epithelium growing into thickened muscularis propria to form intramural diverticula which may contain inspissated bile, mucus, stones, sludge and cholesterol Localized (fundal mass) most common, segmental, diffuse Resulting in luminal narrowing (waist) Reverberation (comet tail) characteristic Distinguish from air and carcinoma Cholesterol Polyps No malignant potential F: M = 2.9: yrs Incidental <10 mm Few associated with cholesterolosis and stones Levy 2002 Gallahan 2010 Adenomyomatosis 8.7 % of cholecystectomy specimens F> M Right upper quadrant pain but over 90% have gall stones Diffuse or segmental wall thickening Sessile or polypoid mass in fundus Anechoic intramural diverticula cystic spaces V-shaped reverberation or comet-tail artifact Cholesterol Polyps Brightly echogenic Round or lobulated Echogenic foci suggestive May detach MR of adenomyomatosis Rokitansky-Aschoff sinuses T2 bright MRI string of pearls sign highly specific (92%) Preservation of mucosal enhancement Allows differentiation from carcinoma CT: intramural diverticula useful also ARP 119

6 Neoplastic 5% Adenomas 4% (5-20 mm) Solitary associated with gall stones Adenoma to carcinoma progression Other: leiomyomas, lipomas, carcinoids, neurofibromas, metastasis, carcinoid, lymphoma Risk factors: Chronic inflammation; 90% have gall stones infection (Salmonella typhi) Elderly Women Porcelain gall bladder (20% in older literature ) Adenomas Uncommon (0.5% autopsy) F> M = 2.4: 1 Asymptomatic and incidental Sessile or peduculated < 2 cm 10% multiple 50-65% associated with stones Adenocarcinoma in 90% Rarely squamous, small cell Usually fundus or neck Diffusely infiltrating mass extending into liver 68% Polypoid intraluminal mass 25% Wall thickening: focal or diffuse Adenomas Smooth intraluminal polypoidal mass Occasionally cauliflower or sessile Adjacent normal wall MRI shows irregular early and prolonged enhancement unlike chronic cholecystitis (Benign processes show early enhancement and washout) > 1 cm wall thickness suggestive MR/CT better for staging 5 th most common GI malignancy but 0.66% of new cancers Incidental in 1-3% at cholecystectomy Vague symptoms, pain, weight loss, fever Presents late with local invasion, biliary dilatation, liver/ln metastasis Poor outcome median survival 3 months Gall bladder polyps Management based on size, presence of gall stones, PSC and sessile morphology Surgery if > 10 mm and > 60 years (Size cut off? 6 mm) < 10 mm follow with US 6-12 months Gallahan ARP

7 GB lymphoma Primary form extremely rare Usually secondary with adjacent disease NHL Difficult to distinguish from carcinoma Adjacent liver mass Diffuse wall thickening Heart failure Hepatitis Hypoalbuminemia Cirrhosis Renal failure Cholecystitis or adjacent inflammation Primary or secondary malignancy XGC Adenomyomatous hyperplasia AIDS Summary Review of imaging features of acute and chronic inflammation Review of polypoidal lesions Benign more common than malignant References L evy AD, et al. Fro m th e Arch ives of th e AFIP Beni gn Tumo rs a nd Tumorlike Lesions o f the Gallbladd er and Extrahepatic Bile Ducts: Radiologic-Pathologic Correlation. RadioGraphics 2002; 22: van Breda Vriesman AC, et al. Diffuse Gallbladder Wall Thickening: Differential Diagnosis. AJR 2007; 188 : Catalano OA, et al. MR Imaging of the Gallbladder: A Pictorial Essay. RadioGraphics 2008; 28: Ching BH, et al. CT Differentiation of Adenomyomatosis and Gallbladder Cancer. AJR 2007 ; 189:62 66 Bennett GL, et a l. CT Findings in Acute Gang re nou s Cholecystitis. AJR 20 02;1 78: Smith EA, et al. Cross-sectional imaging of acute and chronic gallbladder inflammatory disease. AJR 2009; 192: Hanbrid ge AE et al. Ima ging evaluation for acu te p ain in th e rig ht u ppe r qu adran t RadioGraphics ; 24 : Marincek B. Nontraumatic abdominal emergencies: acute abdominal pain: diagnost ic strategies. Eur R adiol (2002); 12: To wfigh S, McFa dde n DW, Cortina GR, Tho mpson JE Jr, To mpkins RK, Cha ndler C, H in es OJ. Po rcelain g allbladd er is not asso ciated with g allbladder ca rcino ma. Am Su rg Jan ;67(1):7-10 Stephen AE, Berger DL. Carcinoma in the porcelain ga lbladder: a relationship revisited. Surgery Jun ;129(6 ): Wantanabe Y, et a l. MR Imag ing o f Acute Biliary D iso rd ers. Ra diographics 20 07; 27: G allahan WC, C onway JD. Diagnosis and Management of Gallbladder Polyps. Gastroenterol Clin N Am 39 (2010) G ore RM, et al. Gallbladder Imaging. Gastroenterol Clin N Am 39 (2010) Rubens DJ. Ult rasound Imaging of the biliary tract. Rad Clin N Am. 2007;2 (3 ): Bennett GL, et a l. CT f indings in a cute gang ren ous cho lecystitis. AJR 2002; 178 : Trowbridge RL, et al. Does this patient have acute cholecystitis? JA MA. 2003;289(1):80-86 Rubens DJ. Ult rasound Imaging of the biliary tract. Rad Clin N Am. 2007;2 (3 ): Ralls PW et al. Real time sonography in suspected acute cholecystitis. Radiology 1985 ; 155 : Smith EA et al. Cross-Sectional Imaging of Acute and Chronic Gallbladder I nflammatory Disease. AJR 2009 : 192 : Parra JA, et a l. Xan thog ranulomatou s Cholecystitis Clin ica l, Sono graph ic, a nd CT Findings in 26 Patient s. AJR ; 174: Boscak A R et al. R adiographics 2006;26: ARP 121