Abdominal CECT scan, special emphasis given on Hepatobiliary pathology, liver pathology

1. Abdominal CT Scan Crossing the barrier in
bedside interpretation

2. Dr. Kazi Mazharul Islam
MBBS(DMC), FCPS, MCPS
Registrar, Hepatobiliary Surgery
Dhaka Medical College Hospital

3. Can a Clinician interpret CT scan
like a Radiologist?

4. Birds eye view
Radio physics
Triple Phase CT scan
Reading a CT film
Abdominal Anatomy In CT scan
Hepatobiliary Pathology

5. R
A
D
I
0
H
Y
S
I
C
S

6. Series of X-ray images taken from
different angles.
Uses computer processing to create
cross-sectional images.

10. Hounsfield Unit

16. Density
The appearance of a structure or lesion in comparison to reference structure
Isodense

17. Hyper
dense
Hypo
dense

18. PHASIC SCAN/
CONTRAST ENHANCED SCAN

19. Non Enhanced CT Scan

21. I/V Contrast injection

22. Early Arterial Phase

24. Late Arterial Phase

25. Small Hepatocellular
carcinoma in cirrhotic
liver not visible on NECT
(left), clearly visible in
arterial phase (middle)
and not visible in portal
venousphase(right)
NECT
Late
arterial
Portal

26. Early Arterial Phase
Late Arterial Phase

27. Hepatic Phase

28. Hypovascular
metastasis
Hyperdense liver
in portal phase

29. Nephrogenic Phase

30. Delayed Phase/ Equilibrium Phase

31. Equilibrium phase or Delayed Phase
 In the equilibrium phase at about 10 minutes after contrast injection,
tumors become visible, that either loose their contrast slower than
normal liver, or wash out their contrast faster than normal liver
parenchyma.
These lesions will become either relatively hyperdense or hypodense
to the normal liver.

32. Cholangiocarcinoma
retaining the
contrast
Haemangioma
retaining the
contrast at
periphery

34. How To Read A CT Scan

35. SECTION/SLICES/PLANES/VIEW

36. Plane/Section View

38.  Standard 64 slice gives cross section with 0.5mm
thickness
256 and 320 slices provide higher accuracy

39. Scout View
It is a mode of operating a CT
system, Used to display slice
locations rather than for direct
diagnosis.

40. Read the information on the CT scan

42.  Always begin cranial and gradually move caudally.
 Assess structures from superficial to deep, first analyze tissues of abdominal
wall and then progress to internal structures

43.  Begin by following one organ
Track it through entire sequence.
 With experience, follow organs that lie in same transverse plane.

44. Abdominal Anatomy in CT Scan

46. Follow the IV contrast filled Aorta as we descend caudally.
Branches and points of interest will be noted.

47. ;IVC
Oesophagus
Aorta

48. ;IVC
Oesophagus
Aorta

50. Azygous Vein. Hemiazygous Vein
;Azygos
Hemi Azygos

51. This is an excellent
image of the right,
middle and left
hepatic veins
draining into the
Inferior Vena Cava.

52. Portal Vein
Branching
into the Liver
Liver

55. Splenic Artery.
Splenic Vein.
Scroll up and
down to
confirm.
Spleen

57. Coeliac trunk
branching into
hepatic artery
proper and
splenic artery

58. S. Mesenteric artery
S. Mesenteric Vein

59. S. Mesenteric Vein
S. Mesenteric artery

67. 01. GB.
02. Pyloric antrum.
03. Liver.
04. Body of
stomach.
05. Transverse
colon.
01
04
05
03
02

72. Pancreatic Pathology
Pancreatic Neoplasm in head and body
Acute Pancreatitis
Pancreatic Pseudo cyst
True pancreatic cyst

73. Acute Pancreatitis

74. Acute Pancreatitis

76. Pancreatic Pseudo Cyst

77. Cystic lesion of pancreas

78. True pancreatic cyst

79. Solid Pseudo papillary Tumor

80. Carcinoma Head of Pancreas

81. Gall Bladder Neoplasm
Early GB neoplasm

82. Advanced GB Neoplasm
GB

83. Liver Pathology
HCC
Haemangioma
Abscess
Simple Cyst
Metastasis
FNH

84. All liver tumors however get 100% of their blood supply from the
hepatic artery.
Hypervascular tumor will be best seen in the late arterial phase.
Hypovascular liver tumor enhances poorly in the late arterial
phase, difficult to differentiate from the poorly enhancing liver
parenchyma, Best seen when the surrounding tissue enhances,i.e.
in the veinous phase at 65-75 sec p.i.

86. Late Arterial phase at 25sec -35 sec
Hyper vascular lesions
HCC (Hepatocellular Carcinoma)
FNH (Focal Nodular Hyperplasia)
Adenoma
Hemangioma
will enhance optimally, Normal parenchyma shows only minimal enhancement.

87. HCC
Solitary,
Multicentric
Diffuse
Calcification – 7%,
 Isodense on NCCT
and Equilibrium phase
Arterial enhancement
and Early washout
Angioinvasive

88. Adenoma
Solitary lesion
Absence of bile ducts
Female predominance
Age 20- 40 yrs
H/O – OCP,
Anabolic steroids
Thin capsule
Vessel in periphery

89. FNH
 Asymptomatic
 Female
predominance
 Age 20 – 50 Yrs
 Central avascular
scar
 Hypodense on
NCCT

90. Haemangioma
Hyperdense in late
arterial phase
Feeling center to
periphery
Delayed washout

91. Portal Phase
Portal phase at 45 sec p.i.
Hypo vascular lesions like
Metastases
Cysts &
Abscesses

92. Metastases:
Hypovascular Metastases:
Colon
Hypervascular Metastases:
Breast, Sarcomas,
Neuroendocrine
tumors,
RCC & Melanoma
Calcified:
Mucinous GI tract
Ovarian

93. Abscess
Non homogenous
Reduced density
Septal / irregular
enhancement
Peripheral / wall
enhancement

94. Hydatid Cyst

95. Hydatid Cyst

96. Simple Hepatic Cyst

99. Don’t let the CT scan replace
your clinical acumen