3 Cystic lesions of the liver Hepatic cysts:Congenital lesions but detected late Usually asymptomaticIsolated or associated with congenital cystic diseaseComplications [ rupture or hge ] lead to symptomsFew mms to several cms in sizeTypical cyst criteriaSharply defined marginPaper-thin wallClear water contents 0-15 HUAbsent :Septations , Calcification, Enhancement, Mural nodules
5 2. Liver abscess [Pyogenic] Frequently occur with no signs of infectionMay present with profound septicemiaMicroabscesses (less than 2cm) cluster or widely scatteredMacroabscesses :Hypo dense lesion, unilocular or multilocularMarginal enhancement 6%Gas containing abscesses uncommon
6 3. Liver abscess [Amebic ] Entameoba Histolytica 10% world widePatients are more often acutely illSingle or multiple near the liver capsuleEnhancing wall is evident with peripheral zone of edema [ Common findings in amebic abscess]
7 Echinococcal disease [Hydatid cyst] Larval stage of E. granulosusCT FEATURES TO DIGNOSE HYDATED CYSTOther cysts specially in the lungWell defined Unilocular or multilocular cyst with marginal calcificationInternal floating shadows Daughter cysts within the large cyst
8 Benign cystic lesions of the liver Hemangioma 20% of hepatic tumoursThe most common benign liver tumour85% are asymptomatic Female: male = 5:150% are multipleGiant hemangioma 6-10 cm in diameter
10 Benign solid lesions of the liver Rare lesions Hepatic adenomaFocal nodular hyperplasia [ FNH ]Angiomyolipoma Fat containing lesion occurs in patients with tuberous sclerosis where other lesions are present in the kidney
11 Focal nodular hyperplasia FNH 8% of all hepatic tumours2nd most common benign hepatic tumour after hemangioma80%- 90% in women 3rd – 5th decades80%- 90% are solitary lesions <5cm in diameterCentral fibrous scar is a characteristic featurePrecontrast CT iso or hypodense lesionArterial phase CT Marked enhancement
12 Malignant Hepatic Lesions Hepatocellular carcinoma The most common primary malignant hepatic neoplasms3rd – 4th decadesmale: female 8:180% of HCC occur in cirrhotic liverSerum AFP and ultrasound [screening]
13 CT findings:Single or multiple masses that are hypo dense to normal liverCalcification may be seenAfter contrast injection [ better triphasic study]Arterial phase heterogeneously enhancing lesion with hypo dense capsulePortal phase hypo dense lesion
14 Malignant Hepatic Lesions Cholangiocarcinoma The 2nd most common primary malignant tumourThree types:Intrahepatic tumour arised from small peripheral ductsOr the major ducts near the heliumOr at the bifurcation of the common hepatic ducts [ Klatskin tumour]CTHypo dense lesion that shows heterogenous enhancementPortal vein invasion is rarely seenSmall dilated ducts around the lesion may be seen
16 Cholelithiasis Cholelithiasis is the condition of having gallstones. This only becomes a problem if the stones cause an inflammation of the gallbladder which is called cholecystitis.This is often secondary to cystic duct obstruction.Nuclear medicine and ultrasound are the imaging modalities of choice in the diagnosis of cholelithiasis although 15% of gallstones appear radiopaque on a KUB.
17 These radiographs were taken as part of an antiquated exam called an oral cholecystogram (OCG). This study clearly demonstrates innumerable radiolucentcholeliths.