Diagnostic Imaging of Pancreatitis

1. Gastro-Intestinal Tract
Pancreatitis

2. Mohamed Zaitoun
Assistant Lecturer-Diagnostic Radiology
Department , Zagazig University Hospitals
Egypt
FINR (Fellowship of Interventional
Neuroradiology)-Switzerland
zaitoun82@gmail.com

5. Knowing as much as
possible about your enemy
precedes successful battle
and learning about the
disease process precedes
successful management

6. Pancreatitis
(I) Acute Pancreatitis
(II) Chronic Pancreatitis

7. (I) Acute Pancreatitis :
1-Etiology
2-Clinical Picture
3-Types
4-Radiographic Features
5-Complications
6-Staging

8. 1-Etiology :
-Refers to acute inflammation of the pancreas and
is a potentially life threatening condition
-The diagnosis of acute pancreatitis is made by
fulfilling two of the following three criteria :
a) Acute onset of persistent, severe epigastric pain
(i.e. pain consistent with acute pancreatitis)
b) Lipase/amylase elevation beyond three times
the upper limit of normal
c) Characteristic imaging features on CECT, MRI
or US

9. -Causes :
1-Alcohol abuse : most common cause of chronic
pancreatitis
2-Gallstone passage/impaction: most common
cause of acute pancreatitis (up to 15% could
develop pancreatitis)
3-Postoperative, post-ERCP, abdominal trauma
4-Hyperlipidemia, hypercalcemia
5-Drugs: azathioprine, thiazides, sulfonamides
6-Inflammation: PUD
7-Hyperparathyroidism
8-Pregnancy

10. 2-Clinical Picture :
-Classical clinical features include :
a) Acute onset of severe central epigastric
pain (over 30-60 min)
b) Poorly localized tenderness and pain
c) Exacerbated by supine positioning
d) Radiates through to the back in 50% of patients
e) Elevation of amylase and lipase are 90-95%
specific for the diagnosis

11. 3-Types :
-There are two subtypes of acute pancreatitis :
a) Interstitial Edematous Pancreatitis :
-Vast majority (90-95%)
-Most often referred to simply as "acute
pancreatitis" or "uncomplicated pancreatitis“
b) Necrotizing Pancreatitis :
-Necrosis develops within the pancreas and/or
peripancreatic tissue

12. Acute edematous pancreatitis, A,B: CT+C, venous phase, demonstrating
diffuse pancreatic enlargement, densification of the peripancreatic fat planes
(long arrows) and acute fluid collections in the left anterior pararenal space
and in the left paracolic gutter (short arrows), without areas of parenchymal
necrosis

13. Acute necrotizing pancreatitis, A,B: CT+C, venous phase, acute necrotizing pancreatitis
in a 52-year-old male patient, diffuse hypoenhancement of the pancreatic neck, body
and tail (arrows on A), compatible with presence of an extensive area of necrosis,
with a small area of preserved parenchyma in the uncinate process (arrow on B), C,D
: CT+C, venous phase, acute necrotizing pancreatitis in a 35-year- old woman,
extensive areas of pancreatic parenchymal necrosis (long arrows) in association with
areas of fat necrosis in the left anterior pararenal space and in the transverse
mesocolon (short arrows).

16. IEP in a 25-year-old woman with alcohol abuse and epigastric pain for
72 hours, axial CT image shows the pancreas (arrowhead) to be
slightly edematous and heterogeneously enhancing, APFCs
(arrows) are seen surrounding the pancreas

17. Pancreatitis with pseudocyst in a 27-year-old woman, coronal CT
reconstruction obtained 5 weeks after acute episode shows
pseudocyst (arrows) with well-defined rim representing the capsule
near the tail of the pancreas, gastric folds are slightly thickened
(arrowheads)

18. Parenchymal necrosis in tail of the pancreas with ANCs in a 34-year-
old man, axial CT image shows necrosis (arrowheads) in tail of the
pancreas as lack of enhancement, multiple ANCs (arrows) are seen
surrounding tail and body of the pancreas

19. WON of pancreatic body, tail, and portion of the head in a 45-year-old man with alcohol
abuse and necrotizing pancreatitis, (a) Axial CT image obtained 6 weeks after acute
onset shows some areas of lower attenuation (arrowheads) in a heterogeneous
collection with a well-defined rim (arrows), representing WON with fat necrosis
involving pancreas and peripancreatic tissues, (b) Axial CT image obtained several
centimeters caudal to a shows WONs extending into right anterior pararenal and left
anterior and posterior pararenal space (arrows)

20. 4-Radiographic Features :
a) US :
-By US, an inflamed pancreas appears
hypoechoic relative to liver (reversal of
normal pattern) because of edema
-US is mainly used for investigation of
gallstones and/or to follow the size of
pseudocysts

22. A stripe of fluid in front of pancreatic tissue marked by
white arrows

23. (a) Transverse transabdominal US image through the upper abdomen
shows a well-defined hypoechoic collection (arrows) with internal
echogenic material (*) representing the nonliquefied components,
(b) US image shows echogenic gallstones and sludge (arrows)

24. b) CT :
-Focal or diffuse parenchymal enlargement
-Changes in density because of edema
-Indistinct pancreatic margins owing to
inflammation
-Surrounding retroperitoneal fat stranding

25. Interstitial pancreatitis, the pancreas is swollen and there is
peripancreatic inflammation, no fluid collections, no pancreatic
necrosis

26. Interstitial pancreatits, CT+C shows satisfactory enhancement of
pancreatic tissue, but there is some loss of marginal definition, in
keeping with edema, and there is moderate swelling of Gerota's
fascia (between arrowheads)

27. Coronal CT image of Interstitial edematous pancreatitis (IEP) in a 34-
year-old man with acute onset of epigastric pain for 12 hours due to
gallstones, pancreas (arrows) is heterogeneously enhanced, with
indistinct margins due to inflammation of peripancreatic fat, some
stranding and minimal fluid (arrowheads) are also present

28. Edema in the pancreas (arrows) and peripancreatic
stranding and fluid (arrowheads)

29. CT+C shows diffusely enlarged pancreas with low density from edema,
note the density of pancreas is less than liver and spleen with IV
contrast, pancreas is wider than abdominal aortic diameter
indicating that it has increased in size

30. Necrotizing pancreatitis, CT+C (a) show a normally enhancing
pancreas on day 1, as the patient's condition worsened, a second
CT was performed on day 3, (b) notice how the greater part of the
pancreatic body and tail no longer enhances indicating necrotizing
pancreatitis (arrows)

31. Necrotizing pancreatits, CT+C, arrow : no enhancement of pancreas
with IV contrast, arrowheads : normal enhancement in the tail of
Pancreas

32. 5-Complications :
a) Pancreatic Necrosis (Necrotizing Pancreatitis)
b) Acute Peripancreatic Fluid Collection (APFC)
c) Pseudocyst
d) Pancreatic Abscess
e) Infected Necrosis
f) Hemorrhage
g) Fistula formation with pancreatic ascites

33. a) Pancreatic Necrosis : (Necrotizing
Pancreatitis)
-Necrosis of the pancreatic parenchyma with or
without necrosis of the peripancreatic tissues
-Diffuse parenchymal (>30% of pancreatic area) or
focal areas (>3 cm) of nonviable parenchyma,
peripancreatic fat necrosis, and fluid
accumulation (Acute necrotic collection “ANC” or
walled-off necrosis “WON”)
-Imaging :
*Lack of parenchymal enhancement
*Often multifocal

34. Drawings illustrate pancreatic necrosis (a), peripancreatic necrosis (b),
and combined pancreatic-peripancreatic necrosis (c)

35. Pancreatic necrosis in a 65-year-old man, (a) Axial CT+C obtained 2 days after
the onset of acute abdominal pain shows peripancreatic fluid and stranding
(arrows) and normal-appearing pancreatic parenchyma, (b) Axial CT+C
obtained 5 days later owing to the patient’s worsening clinical condition
reveals an ill-defined hypoattenuating region in the body of the pancreas (*),
a finding that suggests pancreatic necrosis, peripancreatic fluid and
stranding (arrows) are also seen

36. Peripancreatic necrosis in a 22-year-old man, (a) Axial CT+C shows stranding,
increased attenuation, and a heterogeneous appearance of the
peripancreatic fat around the body and tail of the pancreas (white arrows), a
feeding tube is seen in the stomach (black arrow), (b) Axial CT+C acquired
20 days later reveals evolution of the heterogeneous peripancreatic
collection into well-defined WON (Walled-off necrosis) (arrows)

37. Combined necrosis in a 46-year-old man, (a) Axial CT+C shows an ill-defined
hypoattenuating region in the body and tail of the pancreas (*), along with ill-
defined heterogeneous peripancreatic fluid, stranding, and increased fat
attenuation (arrows), (b) Axial CT+C acquired 6 weeks later reveals
evolution of the pancreatic and heterogeneous peripancreatic collection into
well-defined WON (arrows), residual pancreatic parenchyma is seen in the
tail (*)

38. b) Acute Peripancreatic Fluid Collection (APFC)
:
-Collections of enzyme-rich pancreatic fluid occur
in 40% of patients
-No fibrous capsule (in contradistinction to
pseudocysts)
-Most common location is within and around the
periphery of the pancreas
-Fluid collections are not limited to the anatomic
space in which they arise and may dissect into
mediastinum, pararenal space, or organs
(spleen, kidney, liver)
-Prognosis: 50% resolve spontaneously; the rest
evolve into pseudocysts or are associated with
other complications (infection, hemorrhage)
-Differentiation from pseudocyst difficult: test of
time

39. Acute pancreatitis, the pancreas is enlarged (blue arrow) with indistinct
and shaggy margins, there is peripancreatic fluid (red arrow) and
extensive peripancreatic infiltration of the surrounding fat (black
arrow)

41. c) Pseudocyst :
-Encapsulated collection of pancreatic fluid, which
is typically round or oval
-Surgical definition of pseudocyst requires
persistence at least 6 weeks from the onset of
pancreatitis
-Occurs in 40% of patients with acute pancreatitis
and in 30% of patients with chronic pancreatitis
-Bacteria may be present but are often of no
clinical significance; if pus is present, the lesion
is termed a pancreatic abscess

43. Chronic pancreatitis with an intrapancreatic pseudocyst in a 42-year-old man
with a history of alcoholic pancreatitis, (a) CT+C shows a dilated pancreatic
duct (arrows) with mild pancreatic atrophy, an appearance compatible with
chronic pancreatitis, (b) CT scan shows a round mass with diffuse low
attenuation in the pancreatic head (curved arrow), the mass represents a
pseudocyst, note the dilated pancreatic duct (straight arrow), (c) CT+C
shows pancreatic calcifications (arrow), a finding compatible with chronic
pancreatitis

44. Chronic Pancreatitis With Pseudocyst And Calcifications

46. d) Pancreatic Abscess :
-Intraabdominal fluid collection in or adjacent to the
pancreas that contains pus
-Effectively treated by percutaneous drainage
-Usually occurs >4 weeks after onset of acute
pancreatitis
-Imaging :
*Circumscribed fluid collection
*Little or no necrotic tissues (thus distinguishing it
from infected necrosis)

47. (a) CT+C shows a heterogeneous hypoattenuating fluid collection with
peripheral irregularity in the pancreatic body and tail (arrow), three weeks
after conservative treatment, a spiking fever and marked leukocytosis
developed, (b) CT scan obtained 3 weeks after conservative treatment
shows an interval increase in the size of the fluid collection, which contains
high-attenuation debris (arrow), the presence of infection was confirmed by
means of percutaneous aspiration

49. e) Infected Necrosis :
-Necrotic pancreatic (and/or peripancreatic)
tissue that can become infected
-Differentiation from pancreatic abscess is
crucial for appropriate clinical treatment
(see table)
-Imaging :
*Difficult to distinguish from aseptic
liquefactive necrosis
*Presence of gas is helpful

51. Large infected WON in a 57-year-old man with necrotizing pancreatitis,
axial CT image obtained 5 weeks after acute onset shows pancreas
replaced by low-attenuation collection with well-defined rim (arrows)
and multiple pockets of gas (arrowheads)

52. Infected acute necrotizing pancreatitis in a 35-year-old man, CT+C, venous
phase showing liquefied area in the pancreatic body, compatible with
necrosis, with gas inside (arrows) without an outlined fluid gas level, but
intermingled with the fluid, indicating the presence of thick fluid/pus content,
in such a context, gas corresponds to the presence of infection

53. f) Hemorrhage :
-Usually occurs as a late consequence of vascular injury,
commonly erosion into splenic or pancreaticoduodenal
arteries
-May result from rupture of pseudoaneurysm
-Imaging :
*High-attenuation fluid in the retroperitoneum or
peripancreatic tissues
g) Fistula formation with pancreatic ascites :
-Leakage of pancreatic secretions into peritoneal cavity

54. NECT shows acute Hemorrhagic Pancreatitis, enlarged tail of pancreas, white
arrow : increased density in the enlarged tail of pancreas due to blood,
fascial changes adjacent to tail of pancreas due to inflammation

55. 6-Staging : CT Staging
-Grade A : normal pancreatic appearance
-Grade B : focal or diffuse enlargement of
pancreas
-Grade C : pancreatic abnormalities and
peripancreatic inflammation
-Grade D : 1 peripancreatic fluid collection
-Grade E : >2 peripancreatic fluid collections
and/or gas in or adjacent to the pancreas

56. (II) Chronic Pancreatitis :
1-Etiology
2-Clinical Picture
3-Radiographic Findings
4-Groove Pancreatitis

57. 1-Etiology :
-The most common cause of chronic
pancreatitis in adults is excessive alcohol
consumption in developed countries and
malnutrition in developing countries

58. 2-Clinical Picture :
-Patients may present with exacerbations
(episodes of acute pancreatitis)
manifesting as epigastric pain, which may
recur over a number of years

59. 3-Radiographic Findings :
a) Plain Radiography :
-Calcification
b) US :
-The pancreas might appear atrophic, calcified or
fibrotic
-Findings that may be present on ultrasound
include :
*Hyperechogenicity (often diffuse) often indicates
fibrotic changes
*Pseudocysts
*Pseudoaneurysms
*Presence of ascites

63. c) CT :
CT features of chronic pancreatitis include :
1-Dilatation of the main pancreatic duct
2-Pancreatic calcification
3-Changes in pancreatic size (i.e. atrophy),
shape, and contour
4-Pancreatic pseudocysts

64. Calcification in an atrophic pancreas

65. Duct dilatation

66. Pancreatic calcifications

68. 4-Groove Pancreatitis :
-Rare form of chronic pancreatitis that may mimic
pancreatic carcinoma
-The term pancreaticoduodenal groove refers to
the potential space between the head of the
pancreas, the duodenum, and the CBD
-Two forms of groove pancreatitis have been
described :
a) Segmental Form :
-Which involves the pancreatic head with
development of scar tissue within the groove
b) Pure Form :
-Which affects the groove only, sparing the
pancreatic head

69. Groove pancreatitis with cystic dystrophy of the duodenal wall, drawing
illustrates the disease process in groove pancreatitis, inflammation
is predominantly centered in the pancreaticoduodenal groove, with
multiple cystic lesions within the medial wall of the duodenum (D)

70. -At CT, the classic finding is soft tissue
within the pancreaticoduodenal groove;
this tissue may demonstrate delayed
enhancement, small cystic lesions may be
seen along the medial wall of the
duodenum

71. Groove pancreatitis with cystic dystrophy of the duodenal wall, (a) Transverse
US image through the pancreas (P) demonstrates a sheetlike hypoechoic
area in the pancreaticoduodenal groove with areas of cystic change
(arrowhead), (b, c) Venous phase CT scans show a hypoattenuating area in
the pancreaticoduodenal groove (arrow in b) with inflammatory stranding
within the surrounding fat and in the right anterior pararenalparaduodenal
space (arrows in c). P = pancreas