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Flashcards in Liver Deck (94):
1

What are the characteristic findings of cirrhosis?

Nodular changes in surface contour
Atrophy of right lobe
Enlargement of left and caudate lobes

2

Caudate lobe enlargement is more prevalent in which type of cirrhosis

Alcohol induced

3

What are the two types of cirrhosis? What are the causes?

Micronodular - innumerable

4

Signal change between in and out of phase imaging in a nodular liver suggest what

Dysplasia - intracellular fat within nodules indicates dysplasia

5

How does blood flow in cirrhosis?

Through the fibrous septations as the acinar sinusoids are blocked

6

What is a recanalized umbilical vein?

Enlarged collateral vein that runs adjacent to the obliterated umbilical vein carrying hepatofugal (away) flow
"Paraumbilical vein"

Seen in portal hypertension

Make up caput medusae

7

What is hepatopetal vs hepatofugal

Hepatopetal is the normal flow in the portal system - blow flows through the portal vein TOWARDS the liver

Hepatofugal is abnormal flow caused by increased pressure AWAY from the liver through the protal vein

8

Wedge shaped ill defined band of abnormal signal (low T1 and high T2)

usually in anterior right lobe and medial segment left lobe

Confluent hepatic fibrosis

9

What is confluent hepatic fibrosis?

Wedged shaped region extending from porta hepatis to periphery

Usually anterior right hepatic lobe or medial left hepatic lobe

Spares veins and doesnt change in shape

10

What is nutmeg liver? How does it look? How does it look on doppler?

Hepatic congestion due to cardiac failure and constrictive pericarditis -> increased central venous pressure -> increased hepatic venous pressure -> sinusoidal engorgement -> diminished hepatic arterial flow -> hepatocellular hypoxia

Reflux of contrast into dilated hepatic veins and IVC, mottled enhancement, cardiomegaly, hepatomegaly, ascites, effusions

Will have pulsatility on doppler from direct transmission of fluid wave from heart through sinusoids

11

What is the cause of focal hepatic steatosis

REgional differences in hepatic blood flow

12

What/Where is the abnormality stored in primary hemachromatosis?

Ferritin and Hemosiderin

Liver - periportal hepatocytes then later biliary epithelium, kuppfer cells, fibrous septa

Pancreas and heart later as well

13

What are the complications of hemachromatosis? Most common cause of death

HCC

Cardiomyopathy, diabetes, arthropathy

14

Key feature differentiating hemachromatosis and hemosiderosis

Pancreas involvement and sparing of spleen in chromatosis

Splenic and marrow involvement with pancreatic sparing in siderosis

15

On MRI, what is a good comparison to determine liver signal abnormality?

Paraspinal muscles

16

What is von gierkes disease

Accumulation of glycogen within hepatocytes and proximal tubules of kidneys

17

Von gierkes has increased incidence of what?

Adenomas - and risk for HCC

18

What is the difference between solitary adenomas and adenomas in von gierkes disease

Von gierkes has an increased risk of HCC

19

What is budd chiari syndrome?

Hepatic venous outflow obstruction

Can be at the hepatic vein level or subdiaphragmatic IVC

20

What is primary budd chiari syndrome? What is the risk of HCC?

Membranous obstruction of hepatic veins

20-40%

21

What is secondary budd chiari syndrome?

Occlusion at the central or sublobular vein or major hepatic vein

22

How does budd chiari show on angiogram

Wedge shaped hepatic venogram with spider web pattern of intrahepatic collaterals (pathognomonic for sublobular collaterals)

23

What is the enhancement pattern of acute budd chiari?

Heterogenous enhancement of liver with normal perfusion of central portion and caudate lobe)

24

DDx for diffusely hyperattenuating liver

Hemachromatosis
Wilsons disease
Drugs (Gold, Amiodarone, Thorium Dioxide)
Glycogen storage disease

25

What are the doses for radiation injury to the liver in single and fractionated doses

Single - 12 Gy
Fractionated 40 Gy

26

What is hereditary hemorrhagic telangectasia?

Autosomal DOMINANT
Multiple AV malformations that lack capillaries

27

DDx for multiple enhancing liver nodules? Differentiate them

Multiple HCC - fast washout on venous, cirrhosis
HHT - will follow vessels
Budd chiari - peripheral changes are absent
Mets - rapid washout

28

What is pseudocirrhosis? What is it associated with?

Lobular hepatic contour with segmental volume loss and caudate enlargment seen in Breast Cancer

29

What is the association ARPKD?

Hepatic fibrois, differs from ADPKD

30

What are the non GI associations with ADPKD?

Berry aneurysms
MVP
Bicuspid aortic valve
Aortic aneurysms and dissections

31

What are von meyenburg complexes?

Clusters of proliferated bile ducts embedded in fibrous stroma

US - can have ringdown artifact from cholesterol crystals in dilated tubules
High signal on T2 with faint rim enhancement or no enhancement

32

Who gets peribiliary cysts? What is the significance?

Liver disease, cirrhotics, Portal venous hypertension, thrombosis, cholangitis, transplant

Asymptomatic

Dilation of intrahepatic peribiliary glands

Intra/extrahepatic ducts are normal

33

Most common bug in pyogenic hepatic abscess? Children?

E Coli (adults)

Staph (kids)

34

Where does entamoeba histolytica invade?

Cecum

35

Where is the abscess in E. histolytica? How does it look on CT? What is aspirated?

Right hepatic lobe

Water attenuation mass with low attenuation ring, solitary

Reddish anchovy paste

36

What is the host for echinococcus granulosus? multiloculare?

Dogs

Cats, rodents

37

How does echinococcus look on imaging? how does multiloculare differ?

Peripherally calcified cystic lesion with visible daughter lesions

Granulosus - can be loculated. Daughter cysts are located in the periphery with lower attenuation

Multiloculare - geographic infiltrating regions of hypoattenuation with poorly defined invasive masses

38

What are the ultrasound findings in candidiasis? CT?

Bulls eye pattern - hyperechoic center with hypoechoic rim
Wheel within a wheel - central hypoechoic nidus with a hyperechoic rim and another hypoechoic rim
Uniformly hypoechoic liver due to progressive fibrosis
Echogenic liver caused by scar formation

Multiple hypoattenuating lesions in liver and spleen on CT

39

What is Kasabach-Merritt Syndrome?

Giant cavernous hemangioma (>4cm) that causes mass effect on adjacent structures, consumptive coagulopathy, and thrombosis

40

What is the blood supply to a hemangioma?

Hepatic artery

41

What is the imaging of hemangioma?

CT
MRI
US

Peripheral globular enhancement that is iso/hyperattenuating to the aorta with progressive centripetal fill in

T1 hypo
T2 hyper (slow moving fluid)
Delayed centripetal enhancement

Homogeneous hyperechoic with increased through transmission - usually doesnt have flow because they are slow moving

42

DDx for echogenic mass in liver?

Hemangioma

Hyperechoic mets - will have hypoechoic halo

Focal fatty infiltration - geographic hyperechoic mass

43

What is the scintigraphy of hemangioma vs mets

Hemagioma will have delayed uptake (1-2 hours)

Mets will have early activity and rapid washout

44

What percentage of hemangiomas are atypical? How do they present on CT? US?

15%

CT - diffuse early enhancement and washout (flash hemangioma)

US - thin hyperechoic rim, hypoechoic mass in diffusely hyperechoic liver

45

What is FNH? Pathophysiology?

Abnormally arranged hepatocytes, bile ducts, and kuppfer cells

Arises as a result of locally increased hepatic blood flow from a hepatic AV malformation

46

How does FNH appear on unenhanced CT? enhanced?

Unenhanced is ISOattenuating

Will have HOMOGENEOUS enhancement during arterial phase

Central scar is characteristic

47

Does FNH have a capsule?

No, but peripheral draining veins can give the appearance of a capsule

48

What makes up the central scar in FNH?

Supplying arteries and bile ductules

49

Key feature of FNH on imaging

HOMOGENEOUS enhancement on arterial phase

50

What is the US feature of FNH?

Central doppler activty with stellate pattern

51

What are the MRI findings of FNH?

Isointense on T1 and T2

Central scar is hypointense on T1 and hyperintense on T2

Homogeneous enhancement during arterial phase

52

What NM test is useful for FNH? How big must it be?

Sulfur colloid - will be taken up by kupffer cells

>2cm

53

What percentage of FNH dont take up sulfur colloid?

30%

54

What percentage of FNH is multifocal?

20%

55

What makes gadoxetate special?

50% excretion from both biliary system and kidneys.

56

What are hepatic adenomas?

Cords of hepatocytes in an abnormal architecture

57

How do adenomas image?

Heterogeneous enhancement with a capsule

58

How are adenomas managed?

Surgical resection due to risk of hemorrhage

59

What is associated with multiple adenomas?

Von gierkes, anabolic steroids, familial diabetes

60

Low attenuation liver with multiple enhancing masses

Von gierkes

61

Hyperechoic mass on US, Fat containing mass on CT

What is the association

AML

Tuberous sclerosis

62

Do liver AML have the same risk of rupture as renal?

No

63

How does a dysplastic nodule present on MRI?

Hyper on T1 and iso on T2

Capsule will be present occasionally

64

What is the nodule in a nodule appearance?

Progression of regenerative nodule to dysplastic nodule with a small focus of HCC

65

Match the following characteristics with type of nodule

Iso on T1/T2

Hyper T1 and iso on T2

Enhancement with rapid washout

Regenerative

Dysplastic

HCC

66

Differentiate the enhancement of dysplastic nodule vs HCC

Dysplastic will enhance during arterial with isointensity on delayed

HCC will avidly enhance during arterial and be hypointense on delayed

67

What are the 3 types of HCC? Which is best prognosis?

Focal - best prognosis, expands rather than invades. Will have capsule

Multifocal

Diffuse

68

What percentage of HCC contain intratumoral fat?

40%

69

Mosaic appearance of solid and cystic regions within a liver mass suggests what?

HCC

70

What is a THAD?

Transient Hepatic Attenuation Defect

71

THAD should prompt a search for what?

Underlying neoplasm causing compression or obstruction of supplying portal vein

72

What findings suggest multifocal HCC vs mets

Dominant mass

73

What findings suggest a tumor thrombus over bland?

Contrast enhancement and arterial doppler waveform

74

What imaging findings are seen after a SUCCESSFUL ablation?

Water attenuation mass without evidence of enhancement

75

What suggest recurrence after ablation?

Enhancing nodularity

76

Large mass with central scar and calcification without underlying cirrhosis

Fibrolamellar or FNH (less likely to have calcs)

77

What are the risk factors for cholangiocarcinoma

PSC
Choledochal cyst
Polyposis syndromes
Congenital hepatic fibrosis
Clonorchis (opisthorchis)
Thorium dioxide

78

How does lymphoma present in the liver on US and CT?

US - multiple small hypoechoic lesions
CT - multiple small low attenuation lesions

79

What are the two strongest risk factors for primary hepatic lymphoma

HIV and Hep C

80

What is post transplant lymphoproliferative disorder? How does it image?

Spectrum of abnormal lymphocyte proliferation ranging from abnormal proliferation of lymphoid cells to frankly malignant NHL

T cell suppressor chemo drugs activate overactive B cells

Solitary or multiple necrotic masses that encase vessels

81

What is a predisposing risk factor for PTLD

EBV

82

What is the rate of PTLD

2-10%

83

Multiple solitary masses in the periphery of the liver that grow together over time and cause capsular retraction

Epithelioid hemangioendothelioma

84

Heterogeneous lacelike liver attenuation with a small atrophic spleen and hyperdense lymph nodes

Thorium dioxide induced angiosarcoma

85

What is the most common liver met? How does it present?

How do breast and lung mets appear?

Hypervascular mets arise from where

Colon - expansile hypoattenuating mass which may calcify (mucin)

Smaller, diffuse/infiltrative

PNET (carcinoma, islet cell, pheo), Melanoma, Thyroid, Renal, Choriocarcinoma, Breast

86

What are the imaging patterns on US for hepatic mets?

Multiple hypoechoic masses

Multiple isoechoic or hyperechoic masses with hyperechoic halos

87

What is the best phase for hypervascular mets?

Arterial

Will usually be isoattenuating on portal venous phase

88

What does a hypoechoic ring surrounding a liver mass suggest on US? What does it represent

Mets or HCC

Normal hepatic tissue compressed by rapidly expanding tumor

89

Hyperechoic mass with posterior shadowing should prompt worry for what?

Hypervascular mets

Shadowing is due to increased vascularity

90

What separates the liver into sup/inf? axially (r/m/l)?

Portal vein

Hepatic vein

91

What are the pathology in schistosomiasis?

Antigens released from eggs stimulate granulomatous reaction

Collagen deposition and fibrosis later on cause organ damage

92

What is the most common GI finding in schistosomiasis?

Periportal fibrosis leading to portal hypertension and GI bleed

93

What are the imaging findings in schistosomiasis?

Abnormal linear branching - Thickened portal tracts and hyperenhancement during portal venous/delayed phases

94

What is the hot caudate lobe sign? What is it seen in?

Increased vascular flow within the medial segment of the left hepatic lobe.

Develops due to SVC obstruction, which leads to intermal mammary vein drainage into the left portal and paraumbilical veins