This document discusses imaging techniques for detecting and characterizing liver lesions. It focuses on multiphase CT and MRI protocols for hepatocellular carcinoma (HCC). CT involves non-contrast, arterial, portal, and delayed phase imaging. Arterial phase highlights hypervascular tumors fed by the hepatic artery. Portal phase detects hypovascular lesions. MRI features of HCC include hypointensity on T1-weighted imaging and hyperintensity on T2-weighted imaging. The Barcelona Clinic Liver Cancer staging system is also referenced.

1. -DR. BHANUPRIYA SINGH
HCC- Malignant Liver
lesion

3. IMAGING TECHNIQUES
 plain radiography : gross hepatomegaly
 calcification
 USG / CE-USG
 CT
 MRI
 Angiography
 Scintigraphy:
 Sulfur colloid , Tc99m labelled RBC’s
 PET

4. CT SCAN
 Non contrast study:
 Contrast study: arterial phase: 20-40secs
Portal phase : 60-80secs
Early delayed: > 180 sec
, best at 4 mins
Late delayed : 4-6hrs
 100ml contrast @3ml/sec

5. Understanding the phases
 Liver -dual blood
supply
 Normal parenchyma -
80% portal vein
 20% -hepatic artery
 All liver tumors blood
supply from hepatic
artery

6. Arterial phase
 20- 40 sec
 Hypervascular tumors
enhance via the
hepatic artery
 Normal liver
parenchyma not yet
enhanced
 Hypervascular tumors
enhance optimally at
35 sec

7. Portal venous phase
 60- 80 sec
 To detect
hypovascular tumors

8. Delayed Phase
 Begins at about >
180 sec
 Best done at 4
minutes

9. Pre contrast Arterial Phase Portal venous
phase
Delayed
Hepatocelluar Ca Low attenuation Homogenous
enhancement
Washout of
lesion
Isodense
Adenoma Low attenuation Homogenous
enhancement 85%
Iso or
hypodense
Iso or hypodense
Haemangioma Low attenuation Peripheral puddles Partial Fill in Complete fill in
FNH Iso/Low
attenuation
Homogenous
enhancement
Hypodense Isodense
Hypervascular Mets Low attenuation Homogenous
enhancement
Hypodense
Metastasis Low attenuation Hypodense Hypodense
Cyst Low attenuation No enhancement
Abscess Low attenuation may
have irregular margins
Transient regional
enhancement
Ring
enhancement
Multiphasic CT of Liver

10. T1W T2W Gadolinium
Hepatocellular Ca
,iso or (fat degeneration)
Metastasis
Haemanigioma
++ (like CT)
Adenoma
often
FNH
+ delayed
FLC
+ delayed
MRI of Liver

11. FOCAL FAT SPARING
 Diagnostic confusion
with tumors
 Common sites
 Periportal region of the
medial segment of left
lobe (segment IV)
 Either side of falciform
ligament
 Cranial aspect of GB
fossa
 Characteristic features:
 Geographic appearance
 Lack of mass effect
 Vessels through the
lesion

12. FOCAL NODULAR LIVER
LESIONS:
• Regenerative nodule
• Cirrhotic nodule
• Low grade dysplastic nodule
(adenomatous
hyperplasia)
• High grade dysplastic nodule
(adenomatous
hyperplasia with atypia)
• Dysplastic nodule with subfoci of HCC
(early HCC)
• HCC (overt HCC)

13. Hepatocellular Carcinoma
 Most common primary malignancy of the liver
 Rising incidence, attributed to a rise in hepatitis B
and C infection
 Typically diagnosed in adults(late middle
age/elderly)
 Pt with cirrhosis present earlier

14. Risk factors:
 hepatitis B (HBV) infection
 hepatitis C (HCV) infection
 alcoholism
 biliary cirrhosis
 food toxins e.g. aflatoxins
 congenital biliary atresia
 inborn errors of metabolism
haemochromatosis
alpha-1 antitrypsin deficiency
type 1 glycogen storage disease
Wilson disease
Hepatocellular Carcinoma

16. USG
 USG - vary
 Small HCC’s (<3cms) ->
hypoechoic with posterior
acoustic enhancement ( fatty
change/ marked sinusoidal
dilatation)
 >3cms- mosaic or mixed pattern
 May invade poratl vein
 CD:central vascularity

22. CT SCAN
 3 patterns:
 Solitary
 Multicentric
 Diffuse
 Large hypodense
mass
 Central low
attenuation due to
necrosis

23. CT
 Focal calcification -
7.5%
 Majority -
hypervascular
 arterial phase
 Heterogenous
enhancement due to
central necrosis
 Isodense on delayed
images
 Angioinvasive: portal
vein /IVC
 Central Necrosis-
Hetrogeneous +C

24. Arterial phase
 Demonstration of
arterial branches
tumour
 Arterio portal shunts
Arterio-portal shunt: The arterial phase CT image shows a
large enhancing lesion (m) in the segments 3 and 4 of liver with
contrast in the left hepatic artery (arrow) and left branch of portal vein
(arrow head) suggesting arterio-portal shunting

26. Portal venous invasion by hepatocellular carcinoma.
portal phase-expanded low attenuation focus in right portal vein.

29. IVC invasion: The axial CT image shows
an exophytic
mass (m) arising from left lobe of liver
extending into the IVC (arrow)

30. MRI
 Small HCC’s v/s regenerative
 Cirrhotic nodule: hyper on T1 , hypo on T2
 HCC : hypo on T1, hyperintense on T2
HCC arising in a siderotic nodule: “nodule within a
nodule” appearance
HCC - a small focus of high signal intensity
within the low signal intensity nodule(T2).

33. Hepatocellular carcinoma and regenerative nodule.
T1w MRI (A) and T2w MRI (B) demonstrating a hepatocellular
carcinoma (white arrowhead) and an adjacent atypical regenerative
nodule (black arrowhead).
Majority of hepatomas have decreased signal intensity on T1WI
-increased signal -fat or glycogen content

36. MRI IN DETECTING EARLY
HEPATO-CARCINOGENESIS

43. BARCELONA CLINIC LIVER CANCER STAGING SYSTEM

44. THANK
YOU