This document discusses the embryology and anatomy of the stomach. It provides the following key points: 1. During embryonic development, the stomach rotates along its longitudinal and anteroposterior axes, causing its final adult position with the cardiac portion on the left and pylorus on the right. 2. The adult stomach is located in the left upper quadrant and extends across the midline, with the greater curvature forming the anterior wall and lesser curvature the posterior wall. 3. Radiological techniques for examining the stomach include barium studies, CT, MRI, and virtual endoscopy, which allow evaluation of stomach morphology, layers, and relationships to surrounding organs.

2. EMBRYOLOGY

3. Sagittal sections through embryos at various stages of development
demonstrating the effect of cephalocaudal and lateral folding on the position
of the endoderm-lined cavity. Note formation of the foregut, midgut, and
hindgut. A. Presomite embryo. B. Embryo with seven somites. C. Embryo with
14 somites. D. At the end of the first month

4. • The stomach appears as a fusiform dilation of the
foregut in the fourth week of development.
• During the following weeks, its appearance and
position change greatly as a result of the different
rates of growth in various regions of its wall and
the changes in position of surrounding organs.
Positional changes of the stomach are most easily
explained by assuming that it rotates around a
longitudinal and an anteroposterior axis

5. Embryos during the fourth (A) and fifth (B) weeks of development showing
formation of the gastrointestinal tract and the various derivatives originating
from the endodermal germ layer

6. • The stomach rotates 90° clockwise around its
longitudinal axis, causing its left side to face
anteriorly and its right side to face posteriorly.
Hence, the left vagus nerve, initially innervating
the left side of the stomach, now innervates the
anterior wall; similarly, the right nerve innervates
the posterior wall.
• During this rotation, the original posterior wall of
the stomach grows faster than the anterior
portion, forming the greater and lesser
curvatures

7. • The cephalic and caudal ends of the stomach
originally lie in the midline, but during further
growth, the stomach rotates around an
anteroposterior axis, such that the caudal or
pyloric part moves to the right and upward,
and the cephalic or cardiac portion moves to
the left and slightly downward. The stomach
thus assumes its final position, its axis running
from above left to below right.

8. Rotation of the stomach along its longitudinal axis as seen anteriorly.
D,E. Rotation of the stomach around the anteroposterior axis.
Note the change in position of the pylorus and cardia.

9. Transverse section through a 4-week embryo showing intercellular clefts
appearing in the dorsal mesogastrium. B,C. The clefts have fused, and the
omental bursa is formed as an extension of the right side of the
intraembryonic cavity behind the stomach.

10. Primitive dorsal and ventral mesenteries. The liver is connected to the ventral
abdominal wall and to the stomach by the falciform ligament and lesser
omentum, respectively. The superior mesenteric artery runs through the
mesentery proper and continues toward the yolk sac as the vitelline artery.

11. ANATOMY

13. RADIOLOGICAL TECHNIQUE

14. Conventional Radiography
• The widespread use of cross-sectional imaging
has significantly diminished the role of
conventional radiographic techniques (plain
radiography and contrast X-ray examinations)
in the diagnosis of diseases of the stomach
and duodenum.

15. Plain Abdominal Radiograph
• Currently, the plain abdominal radiograph
remains a first-line investigation in the acute
setting; although there is a clear move
towards cross-sectional techniques such as US
and CT as part of the initial patient
assessment.
• In the non-acute situation, plain abdominal
radiography offers little information and is
now almost obsolete.

16. CAUSES OF A MASSIVELY
DILATED STOMACH
• Mechanical gastric
outlet obstruction
• Duodenal or pyloric
canal ulceration
• Carcinoma of pyloric
antrum
• Extrinsic compression
• Paralytic ileus
• Surgery
• Trauma
• Peritonitis
• Pancreatitis
• Cholecystitis
• Diabetes
• Hepatic coma
• Drugs
• Gastric volvulus
• Intubation
• Air swallowing

17. Gastric Dilatation
• Mechanical gastric obstruction caused by
peptic ulceration or carcinoma often leads to a
huge fluid-filled stomach that occupies most
of the abdomen and is demonstrated as a
soft-tissue mass with little or no bowel gas
beyond.

18. • Usually a little gas is present
in the stomach, which allows
the organ to be identified.
• When supine, a gas-filled
stomach can usually be
identified with the wall of the
greater curvature convex
caudally and the pyloric
antrum pointing cranially. It
is important to differentiate a
distended stomach from a
caecal volvulus, which may
also be positioned beneath
an elevated left
hemidiaphragm. Acute gastric dilatation after trauma

19. Complication of endoscopy.
A linear collection of intramural gas surrounds
the stomach

20. X-ray contrast studies
• Although largely replaced by endoscopy, X-ray
contrast studies remain the basic radiological
technique for investigation of diseases of the
oesophagus, stomach, and duodenum.
• Barium meal is used for examination of the
lower oesophagus, stomach, and duodenum

21. • high-density barium suspension
• The best results are achieved using either
high-density barium (200% wt/vol – i.e. E-Z-HD)
or intermediate density (100% wt/vol)
barium such as Baritop

22. • There are four basic techniques to the
performance of this examination:
– compression,
– mucosal relief
– barium filling and
– double-contrast

23. SINGLE-CONTRAST EXAMINATION
• A properly performed single-contrast
examination will emphasize :
– mucosal relief,
– compression and
– barium filling.

24. Mucosal relief radiographs
• Obtained at the onset of the examination in
both the prone and supine positions with
approximately 60–90 ml of barium.
• The objective being demonstration of the
gastric fold pattern.
• The anterior gastric wall is evaluated on the
prone images, an area that may not be well
demonstrated on a routine double-contrast
examination.

25. Compression filming
• The stomach is moderately distended with barium
suspension. The amount of barium administered should be
sufficient to spread the rugal folds in the antrum.
• Only those portions of the stomach distal to the inferior rib
cage are accessible to compression.
• Images may be obtained with the patient prone, supine
and/or upright on the radiographic table.
• It should be appreciated that compression filming
demonstrates both the anterior and posterior walls of the
distal stomach.
• Many ulcers and masses can be demonstrated in the
compressible areas of the stomach.

26. • Compression of distal
antrum with patient
upright. Rugal folds are
well seen. The
descending duodenum
overlies in antrum.
Note: Pylorus (P).

27. DOUBLE-CONTRAST TECHNIQUE
• An anti-peristaltic agent such as glucagon or buscopan is
often employed to delay filling of the small bowel during
the study.
• Glucagon produces gastric hypotonia within 45 s of the
injection. It also tends to delay gastric emptying, allowing
better views of the antrum and the body of the stomach.
– Contraindications: pheochromocytoma and insulinoma.
• Buscopan produces transient hypotonia of stomach and
duodenum. In addition, it causes pyloric relaxation,
allowing excellent double-contrast views of the duodenum.
– Contraindications: glaucoma, potential cardiovascular side
effects

28. • The double-contrast technique involves the ingestion
of an effervescent, gas-producing agent composed of
sodium bicarbonate and an antifoaming agent.
• When swallowed with a small amount of water, the
granules or tablets release 300–500 ml of carbon
dioxide, which distends the stomach.
• The gastric walls are then coated with 100–150 ml of
ingested high-density barium suspension. The density
of the barium used in these examinations is typically
around 250 per cent weight/volume.

29. • Double-contrast technique provides exquisite
detail of the mucosal surface of the stomach.
• Lesions on the dependent surface of the stomach
(the posterior wall in the supine patient) are best
seen using double-contrast technique.
• Anterior wall lesions may be more difficult to
identify. For that reason, compression and/or
mucosal relief filming is frequently employed in
conjunction with double-contrast technique.
• This, in effect, is a ‘BIPHASIC’ upper
gastrointestinal barium examination.

30. Limited double-contrast examination
• Part of the conventional single-contrast
examination using air ingested with
swallowing or by drinking through a straw.
• Given the lower density of the barium utilized,
this is not as sensitive as the dedicated
double-contrast examination.

31. EXAMINATION WITH WATER-SOLUBLE
CONTRAST MEDIA
• Evaluate a suspected perforation.
– Barium may lead to granuloma formation and peritoneal
fibrosis.
• If aspiration is suspected or likely, water-soluble, non-ionic
(low osmolar) contrast media should always be used first.
– An ionic, water-soluble contrast medium such as Gastrografin
must be avoided as it can cause severe pulmonary oedema if
aspirated.
• The patient must be examined in both prone and supine
positions to preclude a leak from the anterior wall.

32. RADIOGRAPHIC APPEARANCE
• Gastric mucosa is characterized by two
features:
– the areae gastricae, which form the mucosal
surface pattern, and
– the gastric rugae, which form the gross or
macromucosal pattern.

33. Normal areae gastricae pattern
• Fine reticular network
produced by barium
trapped in criss-crossing
grooves (sulci gastricae)
dividing the gastric
mucosa into 2–4 mm
polygonal islands of
mucosa.

34. • 50–75 per cent of high-quality double-contrast
barium studies,
• most often in the antrum and body.
• The pattern is rarely seen on single-contrast
studies
• not usually visualized endoscopically unless a dye
such as methylene blue is applied to the mucosa.
• Visualization of the areae gastricae is considered
an indicator of adequate coating of the stomach.

35. Areae gastricae. The normal pattern seen with
a well-coated gastric mucosa at barium meal
Abnormal areae gastricae. The pattern is
disturbed in this patient with a carcinoma
of the fundus not noted at endoscopy (also
note the gastric diverticulum)
• Abnormalities of the areae gastricae may be seen in peptic ulcer disease (PUD), particularly
in Helicobacter pylori infection, where they may be enlarged forming a coarser pattern.
• Focal distortion or absence of the areae gastricae pattern is often seen with gastric tumours.
• In diffuse atrophic gastritis the normal areae gastricae pattern is absent.

36. Gastric rugae
• Smooth folds that tend to parallel the long axis of the
stomach
• About 3–5 mm thick on barium studies.
• These comprise mucosa and a portion of submucosa.
• Abnormalities:
– Thicker and nodular rugal folds
– Infiltrative disease (e.g. scirrhous carcinoma) may efface
the rugae.
– Disruption of the normal longitudinal orientation of the
rugae.
– Radiating folds converging to a central point with healing
gastric ulcers.

37. • Three dimensional anatomic relationship
– to properly position patients for upper gastrointestinal
studies
– demonstrating each portion of the stomach and its
relationship to adjacent structures.
• The fundus lies posteriorly in the left upper quadrant
while
• the body and antrum course on a relatively horizontal
plane to lie anteriorly and cross the midline.
• The distal antrum courses posteriorly to the right of
the spine with the pylorus directed posteriorly.

38. • CT of normal stomach
distended with positive
contrast and air.
(A) Normal soft-tissue
prominence at gastro-oesophageal
junction.
Fundus is posterior. The
body courses anteriorly.
(B) On a slightly more caudad
image, the antrum turns in a
posterior direction. Normal,
thin gastric wall is seen. Note
relationships to liver, spleen,
colon and diaphragm.

39. • The greater curvature forms the anterior wall
of the stomach and, similarly, the lesser
curvature forms the posterior wall.
• Variability in the length of the mesenteric
attachments leads to a more horizontal
orientation of the stomach in muscular and
obese people, and a more vertical orientation
in slender people and in the geriatric
population.

40. CT - Technique
• spiral CT > standard CT
• MDCT – improved multiplanar capabilities.
• Water as a negative oral contrast agent
– good visualization of the underlying enhancing
mucosa
– improved 3D reconstruction (because there is no
intervening positive contrast material in the lumen.)

42. • The gastric cardia to adequately distend, an
effervescent agent can be incorporated.
• Positioning of the patient in the left lateral
decubitus or left posterior oblique positions
can improve distension of the antrum and
cardia.
• Positioning the patient prone improves fundal
distension.

43. • With fast scanning, virtual gastroscopy has
developed and may further improve lesion
detection and staging of gastric cancer

44. Aspects of CT anatomy
• A well-distended stomach has a wall thickness
of approximately 5 mm. This measurement
should be obtained in between the rugal folds.
• Layered enhancement of the normal gastric
wall
– The mucosa brightly enhances, while the
submucosa remains lower in attenuation. The
muscular-serosal layer has moderate
enhancement.

45. The normal appearance of the gastric wall may only
have a single, two- or three-layered appearance
• CT scan performed
during the arterial
phase shows normal
single-layer
enhancement of the
gastric wall (arrow).

46. The normal appearance of the gastric wall may only
have a single, two- or three-layered appearance
• CT scan performed during the arterial phase shows normal double- (arrow) and triple-layer
(curved arrow) enhancement of the gastric wall. Hyperenhancing mucosa is easily identified
with water used as a negative oral contrast agent.
• B: Portal venous phase image through the same region demonstrates a more homogeneous
mural enhancement without stratification

47. Virtual Gastroscopy
• This technique can
likewise be applied to
the stomach for virtual
evaluation. Following
air distension of the
stomach we can apply
the ‘fly-through
technique’ to the
stomach to visualize the
gastric folds, pylorus
etc.
Normal appearance of gastric folds as seen on the
virtual endoscopy. Image shows a view from the
fundus looking into the body of the stomach. (B)
Normal appearance of the pylorus as seen on the
virtual endoscopy

48. MRI - Technique
• Patient preperation
– Fasting for 4 – 6 hours
– 500 – 1000mL contrast for optimal distension
– Antiperistaltic agent – buscopan
– Positioning – tumor location
– GE jn – ECG gating

49. Conventional MRI
• Combination of T1-weighted spoiled gradient echo
with and without contrast enhancement and
• T2-weighted single shot turbo spin-echo sequences
using breathhold techniques to avoid misregistration
errors.
• The field of view (FOV) used is 400 × 400 mm
• Matrix size of 192 × 256 mm
• Slice thickness between 8 and 10 mm
• voxel size of between 25.96 and 32.45 mm.
• Axial planes together with sequences perpendicular to
the plane of the tumor to asses for resectability

50. High-Resolution MRI
• External Surface Coil
– For tumors at the gastro-esophageal junction
• single-shot coronal T2-weighted sequence also acquired
– cranio-caudal extent of the tumor
– extension of disease above and below the diaphragmatic hiatus
• Diffusion-weighted imaging
– locally advanced (T3/T4) tumors, showing resticted
diffusion (Sakurada et al. 2009).
– hoped to differentiate benign from malignant lymph
nodes.

51. • Endoluminal: Endoscopic coils
– optimum coil positioning close to the site of the
tumor and
– clearly overcomes the difficulty of motion artifact
(Kulling et al. 1997).

52. An endoscope used for endoscopic MR imaging is not very different from other gastroscopes, but it is
manufactured with materials that do not produce artefacts which interfere with imaging. a The endoscope
used by Dux et al (2001). The tip of the endoscope b shows the oversized biopsy channel that is used to
advance the coil into the stomach. c The prototype of the receiver coil used nowadays. The diameter of the
coil released from the endoscope is variable depending on the size of the tumour that is to be imaged. d
shows that the endoscope is compatible with MRI, and the channel that accommodates the receiver coil is
clearly depicted

53. • Endoluminal: Endoscopic and Expandable
surface Coils
– self-expanding loop coil.
– enables high-resolution imaging of the primary tumor
• location adjacent to the tumor and
• Larger diameter of the coil (8 cm) than the endoscopic MR
increasing the radius for receiving signal from 3–4 cm to 8
cm.
– detailed analysis of the depth of tumor invasion
through the layers of the stomach wall and
– assessment of involvement of the gastric serosa and
surrounding tissues (Heye et al. 2006).

54. Endoscopic MR imaging of the
stomach.
• The receiver coil (arrowheads)
was advanced into the lumen
of the stomach and covers an
area of 9–10 cm that can be
used for imaging.
• A small early gastric
carcinoma (arrow) is located
within the gastric wall and has
infiltrated the submucosa. The
submucosa is represented by
the middle, hypointense layer
of the gastric wall (∗)

55. Normal Anatomy on MRI –
Wall Layers
• Endoluminal coil demonstrates the main
component layers of the stomach wall:
– The mucosa (low signal intensity),
– submucosa (low or high signal intensity,
dependent on the sequence parameters), and
– muscularis propria (low signal intensity) on both
T1- and T2-weighted sequences (Inui et al. 1995).

56. Sometimes two layers may be distinguished using T2-weighted sequences (arrow, a). In addition
a polypoid tumour (arrowhead) of the gastric wall is visible. The patient was positioned prone,
and water was used for luminal distension. In contrast, experimental high-spatial-resolution MR
imaging of the stomach reveals three layers of the gastric wall
b. Opposed-phase imaging shows an early gastric carcinoma (∗), type I, that does not penetrate
the second/middle gastric wall layer. (1) mucosa, (2) submucosa, (3) muscularis propria

57. • The muscularis propria layer as three distinct
layers:
– the inner circular muscle (low signal intensity),
– interposed connective tissue (high signal)and
– the outer longitudinal muscle layer (low signal
intensity) (Yamada et al. 2001; Heye et al. 2006)

58. Normal Anatomy on MRI –
Surrounding Structures
• superior soft tissue contrast
– particularly when structures lie in direct contact
with no interposing fat plane.
• multi-planar capability
– assessment of the relationship of the stomach to
the pancreas, left lobe of the liver, and transverse
colon.

59. Clinical Application:
Staging of Malignant Disease
• T Staging
– Assessment of resectability
• N staging
• Metastatic disease
– Characterisation of focal liver lesions
– Identify peritoneal infiltration

60. T Staging
Experimental high-spatial-resolution MRI of gastric specimens
Opposed-phase imaging is best suited to diagnose gastric tumours because of their high signal
intensities. The images show a carcinoma (∗) of the gastric antrum that involves the whole
circumference of the gastric wall. At histology and MRI, mesenteric infiltration (arrow) was
diagnosed and the tumour finally was staged pT4.

61. T Staging
• An axial view of a gastric
specimen at T2-weighted
imaging.
• The carcinoma (∗) penetrates the
gastric wall and infiltrates liver
tissue that therefore was
resected.
• Local invasion of the liver was
correctly depicted by MRI that
showed tiny areas of signal
intensity changes (arrow) within
the liver parenchyma.
• Compared to that of the primary
tumour the areas of focal
invasion have similar signal
intensities

62. N Staging
• A signet ring cell
carcinoma (∗) involving
more than two-thirds of
the gastric wall as well
as locoregional lymph
node metastases
(arrows) that have
signal intensities
identical to that of the
primary tumour.

63. Clinical Application :
Evaluation of Gastric Motility
• assessment of gastric emptying
• Increased or decreased gastric motion can be
reliably distinguished with MRI; this imaging
modality may be an attractive alternative to
conventional invasive diagnostic tools for
diagnosis of gastric motility disorders and
consecutive therapeutic monitoring (Ajaj et al. 2004).

64. Endoscopic Ultrasound of the
Stomach
• two basic types of
echoendoscope
– radial or linear array transducer
technology.
– The bowel is a tube- radial
scanning is the most
appropriate.
• Doppler facilities
• Miniprobes
• The use of contrast-enhanced
EUS has been discussed and
may in selected cases add
further additional information
(Nomura et al. 1999).
Close-up of the tip of the Olympus GF-UM200
echoendoscope demonstrating
the partially inflated water-filled balloon

65. Bowel Wall Anatomy
• The normal stomach wall at 12 Mz.
The five layers, between arrows, are
well demonstrated. b= water-fi lled
balloon and associated ring-artefacts.
• Close-up of image
1. an echogenic layer representing the
interface between the balloon (b)
and the superficial mucosa,
2. a hypoechoic layer representing the
deeper mucosa including the
muscularis propria,
3. an echogenic layer comprising the
submucosa,
4. a hypoechoic layer, the muscularis
propria, and
5. the echogenic serosa

66. Bowel Wall Anatomy
• Higher-frequency probes are able to identify
up to nine distinct layers including the circular
and longitudinal muscle components of the
muscularis propria.

67. • The coeliac trunk with
its common hepatic and
splenic artery branches
are useful landmarks
with significant
importance for tumour
staging.
Coeliac trunk and its major divisions likened to a
“whale’s tail”. Ao= aorta, CT= coeliac trunk, SpA=
splenic artery, HA= hepatic artery

68. Applications - Benign Pathology
• Submucosal Lesions
– Gastrointestinal stromal
tumours (GISTs) have a
characteristic
appearance and usually
arise from the fourth
hypoechoic layer
corresponding to the
muscularis propria,
A stromal tumour (*) clearly arising from the muscularis
propria (arrows) of the stomach wall. Imaging features
suggest an entirely benign lesion

69. • a lipoma is seen as a
well-defined mass,
more echogenic than a
GIST, usually confined
to the submucosal layer
displacing adjacent
muscle layers
A lipoma (*) arising from the submucosal layer
(sm) of the stomach wall. The muscularis propria (mp) is
displaced but not directly involved

70. • An intramural gastric lesion
(*) with indeterminate EUS
imaging features. The
precise layer of origin deep
to the muscularis mucosa
(arrow) is unclear.
Diagnostic uncertainty and
noncontributory biopsies
necessitated surgical
resection. Aberrant
pancreas proven
histologically

71. • Thickened Folds
– which wall layers are causing
the thickening and
– whether or not the layered
structure is preserved.
• Thickening of the mucosa is
seen in various types of
gastritis, Ménétrier’s disease,
and some patients with early
lymphoma.
• More generalized thickening
with loss of the layer structure
suggests malignancy, such as
advanced lymphoma or linitis
plastica. Enlarged submucosal gastric vessels
(arrows). Identification of intramural and
adjacent vessels clearly important if trans-gastric
biopsy or drainage is being
considered

72. Applications - Malignant Pathology
• Gastric Cancer
– T Staging

73. • Gastric tumour (T).
• There is definite localised
breach of the muscularis
propria (white arrow),
suggesting T3.
• Muscularis propria (mp)
elsewhere intact

74. Applications - Malignant Pathology
• Gastric Cancer
– Nodes
• Lymph nodes are well
seen, and certain features
correlate well with
malignant infiltration:
– Nodes greater than 1 cm
diameter, with
– well-defined margins,
– rounded and
– hypoechoic are likely to be
involved (Catalano et al. 1991).
A perigastric lymph node (n) measuring 14
mm in diameter with imaging features
suggesting metastatic involvement

75. • The presence of direct
invasion into adjacent
structures (T4) can be
difficult to establish on
both CT and EUS.
• Using CT, the suggestion
of invasion is often based
solely upon the area of
contact with the
contiguous organ, but
EUS also allows
evaluation in real-time,
and free movement
between the tumour and
the adjacent organ
(particularly the liver)
excludes direct invasion
Sizeable T2 gastric tumour.
Arrow demonstrates clear line of separation
from the adjacent liver (L). Realtime scanning
demonstrated obvious movement between
the tumour and the liver, making invasion
unlikely

76. • Small-volume ascites,
frequently undetected
by other imaging
modalities, can also be
demonstrated with EUS,
and will alert the
surgeon to the
possibility of peritoneal
spread.
Ascites (*) between the free edge of the left
lobe of liver (LL) and the left hemi- iaphragm
(arrow)

77. Gastric Maltoma
• EUS has been shown to
be more sensitive than
endoscopy or CT for
accurate staging and
crucial for predicting
tumour response to
bacterial eradication
(Ruskoné- Formestraux et al. 2001).
Patient with biopsy-proven maltoma following a
course of H. pylori eradication. Post-treatment
biopsies suggested disease-free, but EUS
demonstrates persistent abnormality (m). Further
targeted biopsies confirmed persistent disease

78. Interventional EUS
• accurate guidance for
– injection,
– biopsy,
– aspiration, and
– drainage

79. Radionuclide Imaging of the Stomach
• simple, noninvasive means of quantifying
gastric motor function and is presently
considered the “gold standard” for this
purpose.

80. Radiopharmaceutical Meals
• Solid, liquid, or semisolid meals
– solid (99mTc-tin colloid in scrambled egg)
– liquid (111In-DTPA in water)
• The radiopharmaceuticals used for gastric
emptying must be nonabsorbable, as this will
reduce the radiation dose outside the GI tract

81. Indications
• symptoms of gastroparesis and diffuse
gastrointestinal dysmotility
• the follow-up of patients who have undergone
various surgical procedures for peptic ulcer and
other GI abnormalities
• Gastric emptying studies are also useful in
quantifying the effect of medical and therapeutic
interventions.
• pivotal role in drug development in recent years

82. Patient Preparation
• fast overnight.
• drugs known to influence gastrointestinal
motility should be discontinued for 24 hours.
• refrain from smoking and consuming caffeine
containing drinks on the morning of the test.

83. • Dual-isotope gastric
emptying study using
solid (99mTc-scrambled
egg) and liquid (111In-
DTPA in water) meals.
• Images were acquired
immediately, 20, 40, 60,
and 120 minutes after
meal ingestion

84. • Liquid Gastric Emptying
– Exponential
• Solid Gastric Emptying
– early lag phase before
the food enters the
duodenum (Sheiner et
al. 1980), followed by a
linear pattern
Gastric emptying curves for solids and liquids in
normal subjects

85. Disorders of Gastric Emptying

86. PET
• Positron emission tomography (PET) has proven itself to be
valuable in the evaluation of patients with gastric cancer.
• The study utilizes [F-18] Fluoro-2-deoxy-glucose as a marker
of tumor activity.
• It is a functional technique that images tissue metabolic
activity.
• Fusion of PET with CT is rapidly becoming the standard of
care when diagnosing malignancy.
• PET/CT is currently used for staging and restaging of gastric
lymphoma as well as following response to therapy.

87. FDG PET/CT. The images depicted show first normal uptake of
FDG by the stomach and second increased uptake in an area of
proven gastric lymphoma

88. PATHOLOGY

89. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

90. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscelleous
• Post surgical
• Neoplastic

91. Congenital
• Gastric duplication cyst
• Gastric diverticulum
• Ectopic pancreas
• Situs anomalies

92. Gastric Duplication cyst
• Gastric duplication cyst is
the least common of the
enteric duplications.
• 7% of GI tract
duplications.
• Usually asymptomatic,
but occasionally present
with vomiting and
abdominal pain.
• Most commonly seen in
infants.

93. Gastric Duplication cyst
• Gastric duplication cyst in a
21-year-old female presenting
with epigastric pain.
• CT reveals a hyperdense cystic
lesion along the medial wall of
the fundus with an air speck
within it suggesting focal
communication with the
stomach.
• Pathology confirmed gastric
mucosa within the cystic
lesion. The age of
presentation, location and
communication with the
stomach are all unusual for a
gastric duplication.

94. Congenital Gastric Diverticula
• Gastric diverticula are
uncommon and usually
asymptomatic (Compared
to duodenal diverticulae).
• Posterior wall of the
gastric cardia are the most
common site.
• Often single, varying in size
from 1 - 3 cm.
• Occasionally can be
multiple and large.

95. • These are true diverticula,
i.e. containing muscularis
propria, and thus are
capable of peristalsis.
• They are usually several
centimetres in size and
readily fill with barium.
• They rarely present a
diagnostic dilemma but may
mimic a submucosal mass if
they fail to fill with barium.
• They may be mistaken for a
gastric ulcer.
Large fundal diverticulum.
The patient is upright and a barium/air level is
present in the diverticulum.

96. • Gastric cardia diverticula
may simulate a left
adrenal mass.
• Air-fluid level, retained
contrast, communication
with stomach and wall
enhancement help in
differentiating it from
other masses.

97. Ectopic pancreas
• pancreatic rest, aberrant pancreas
• presence of pancreatic tissue in the submucosa of the luminal
gastrointestinal tract.
• MC along the greater curvature of the antrum.
• The ectopic pancreatic tissues are usually solitary deposits that
appear as sharply defined submucosal nodules usually <2 cm. A
central depression that collects barium, thought to represent a
rudimentary duct, is present in about 50 per cent of cases.
• When this is present, the appearance is pathognomonic.
• If there is no central depression, the appearance is indistinguishable
from other small submucosal lesions.
• If the central barium collection is prominent, ulceration is a
diagnostic consideration.

98. Ectopic Pancreas in the stomach.
Double Contrast barium study (a) shows a small nodule in the antrum of the stomach (bottom
left of image).
Endoscopy (b) demonstrates the characteristic round umbilicated lesion situated a few
centimeters proximal to the pylorus. Biopsy confirmed ectopic pancreas (pancreatic rest)

99. Pancreatic rest.
• The typical position in
the gastric antrum and
the small pit due to the
rudimentary duct gave
the clue to the
diagnosis

100. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

101. Helicobacter pylori and diseases of
the stomach
• H. pylori is a Gram-negative, flagellated, spiral
bacterium recognized as the most important
cause of:
– PUD,
– chronic gastritis,
– gastric ulcer,
– duodenitis,
– duodenal ulcer and
– Adenocarcinoma
– MALT lymphoma

102. PREVALENCE OF HELICOBACTER PYLORI
INFECTION WITH UPPER GI DISEASE
Disease Prevalence(%)
Active chronic gastritis 100
Duodenal ulcer 95
Gastric cancer (body or antrum) 80–95
MALT lymphoma 90
Gastric ulcer 60–80
Nonulcer dyspepsia 35–60
Asymptomatic population 20–55

103. • Acute infection initially injures parietal cells
causing decreased gastric acid production.
• This is followed by the chronic stage of
infestation, which is localized to the distal
stomach and duodenum. Parietal cell function
recovers, leading to abnormally high acid output.
This causes antral gastritis and duodenitis, with
approximately 1 per cent of infected patients
developing peptic ulcers every year.

104. Gastric ulcer
• penetrate the stomach wall through the mucosa into the
submucosa and frequently the muscularis propria
• Among the most common gastrointestinal disorder and is amenable
to reliable radiographic detection.
• 95 % benign
– H. pylori (70 %)
– NSAIDs
– Alcohol abuse
• most prevalent in the distal stomach and along the lesser curvature.
• more common on the posterior wall of the stomach
• NSAID- and alcohol-related ulcers are most often seen on the
greater curvature of the antrum (direct toxic effect of the ingested
material)

105. Findings Benign Malignant
Extends beyond gastric wall Yes No
Folds Smooth, even Irregular, nodular, may fuse
Associated mass Absent Present
Ulcer shape Round, oval, linear Irregular
Healing Heals completely Rarely heals
Hampton's line Present Absent
Carman meniscus Absent Present

106. En face appearance of benign gastric ulcer.
(A) Posterior wall ulcer is nearly filled with barium in this RPO projection. Thin regular radiating folds (best
seen around the inferior border of the ulcer) are seen converging to the ulcer.
(B) Unfilled benign ulcer crater is outlined by a ‘ring’ shadow. This ulcer is surrounded by a prominent ring of
oedema – the lucent area around the crater.

107. Profile views of benign gastric ulcer.
(A) Hampton's line, a thin line of radiolucency crossing the opening of an ulcer, a virtually
infallible sign of a benign ulcer.
(B) Lesser curvature ulcer with a clearly visible ulcer collar.
(C) Large lesser curvature ulcer niche, its projection from the lumen of the stomach strongly
suggesting a benign lesion.
(D) Smooth, straight radiating folds converge at the ulcer crater.

108. Benign lesser curve ulcers:
double-contrast barium meal study shows a benign penetrating lesser curve ulcer
seen in profile.
A benign lesser curve ulcer seen en face

109. Healing ulcer
• As benign ulcers heal they may
change shape from round or
oval to linear crevices. There
may be subtle retraction or
stiffening of the affected wall.
• An easily recognizable
radiographic sign of healed
gastric ulcer is the presence of
folds converging to the site of
the healed ulcer. There may be
a residual central pit or
depression. The radiating folds
should be uniform.
Note the linear scars extending right to the
ulcer edge and the lack of distortion of the
areae gastricae

110. Healing gastric ulcer.
(A) Focal retraction along the incisura angularis with small residual out-pouching is
present. Converging smooth folds no longer fill an ulcer crater.
(B) Radiating folds converging to a linear scar.

112. • Incomplete healing, irregularity of the folds,
residual mass or loss of mucosal pattern all
suggest the possibility of an underlying
malignancy

113. Malignant gastric ulcer.
• The term ‘malignant
ulcer’ is used to indicate
an ulcer within a gastric
mass, usually a
carcinoma.
• Note the clubbing and
fusion of some folds

114. Carman meniscus sign and gastric adenocarcinoma.
Image from a single-contrast upper gastrointestinal study shows a large filling defect (arrows) in
the antrum with a large central ulcer (*) convex relative to the lumen
Kanne J P et al. Radiographics 2006;26:129-142

115. Kirklin’s meniscus complex
• Consists of Carmen’s meniscus sign plus elevated rim of tumor
surrounding crater
• Ulcer - Barium filled
• Halo - Rim of malignant tissue

116. Malignant Lesser Curve Ulcers
Irregular ulcer crater with nodular and
amputated radiating mucosal folds indicating
infiltration
a “Carman meniscus” sign (arrow) is seen,
which represents the ulcer crater with an
associated elevated border

117. Gastric Ulcer on CT
Benign gastric ulcer on the posterior
Wall of the stomach.
Note the sharp margins of the ulcer
crater (arrows) and evidence of the
ulcer burrowing into the gastric wall.
A malignant gastric ulcer on the posterior wall
of the stomach.
Note the somewhat heaped up ulcer crater
margins (arrows) and the more intraluminal
position of the ulcer.

118. Lymphoid Follicular Hyperplasia
• H. pylori infection is also
related to the presence
of lymphoid follicular
hyperplasia, which is
commonly present in
patients with peptic
ulcer disease (Torigian
et al. 2001).
Follicular lymphoid hyperplasia:
double-contrast barium meal study shows follicular
lymphoid hyperplasia involving the antrum

119. Gastric Erosions or Aphthous Ulcers
• Shallow ulcerations that do not penetrate the
muscularis mucosa
• Usually appear as small, shallow collections of
barium 1–2 mm in diameter’ erosions.
• Gastric erosions are most often causally related
to H. pylori infection. Other causes include
alcohol, NSAID ingestion and crohn's disease.
They may also be seen as a response to stress, for
example in patients with severe trauma.

120. Erosive gastritis:
double-contrast barium meal studies in two different patients
demonstrating erosive gastritis involving the antrum (a) and the
entire stomach (b)

121. ‘COMPLETE’ or ‘varioloform’ - surrounded
by a radiolucent rim of oedema.
‘INCOMPLETE’- halo of oedema is
lacking

122. Gastritis
• Descriptive term with sometimes conflicting
pathological, endoscopic and radiographic definitions
• H. Pylori has been shown to be the most common
cause of gastritis
• The most common findings (H. pylori) are:
– Thick (>5 mm) folds with or without nodularity.
– Erosions
– Others - antral narrowing, inflammatory polyps and
prominent areae gastricae.
• Combination of thick folds and enlarged areae
gastricae may be the most specific findings

123. • Diffuse erosive gastritis
with thick nodular
folds. Erosions are
scattered along the
folds

124. Chronic antral gastritis with several rows of erosions converging towards the pylorus
(a), also shown on the double-contrast barium meal (b)

125. Atrophic gastritis
• combination of atrophy of the gastric glands with
histological inflammatory changes
• Associated with pernicious anaemia and is more
common with advancing age
• Loss of parietal and chief cells leading to
achlorhydria, and atrophy of the mucosa and
mucosal glands
• Intestinal metaplasia, which may be seen
histologically in atrophic gastritis, is considered a
premalignant condition.

126. • Radiographic findings
include:
– loss of rugal folds and
– a tubular, featureless
narrowed stomach.
– Areae gastricae may be
absent

127. Hypertrophic gastritis
• Misnomer - inflammation is not a prominent
• Associated with glandular hyperplasia and
increased acid secretion .
• There is a high prevalence of duodenal and
gastric ulcers in these patients.
• D/d - Ménétrier's disease and lymphoma

128. • Characterized
radiographically by
thickened folds, often
greater than 10 mm in
width, predominantly in the
fundus and body, which are
the acid-producing regions
of the stomach.
• The areae gastricae pattern
may be prominent, up to 4–
5 mm in size and more
angular and polygonal than
the usual round or oval
configuration
Hypertrophic gastritis in a patient with a recently healed lesser curvature
gastric ulcer. This characteristic enlargement and prominence of the areae
gastricae can be correlated with an increased incidence of gastric
hypersecretion and PUD

130. Ménétrier's disease
• characterized by
– hypertrophy of gastric glands,
– achlorhydria and
– Hypoproteinaemia - protein-losing enteropathy -
manifests as increased fluid in the small bowel.
• While in the classic description of Ménétrier's
disease the antrum is spared, it has been found
to be involved in up to 50 per cent of cases
causing diffuse involvement of the stomach.

131. • markedly enlarged, often
bizarre gastric folds most
prominent in the proximal
stomach and along the
greater curvature.
• massively thickened often
lobular folds.
• The folds remain pliable,
– D/D - carcinoma, where
the stomach becomes rigid
and aperistaltic. Classic appearance with massively distended
folds in the body sparing the antrum.

132. • CT – uniform thickening
of the gastric wall that
may be as much as 1–2
cm.
• The most important
differential diagnosis is
lymphoma (Williams et al. 1978).
Ménétrier’s disease. Coronal reformation
shows large, lobulated folds and preserved
gastric mucosa of the fundus in a patient with
biopsy-proven Ménétrier’s disease

133. Eosinophilic gastritis
• focal or diffuse infiltration of the gastrointestinal tract
by eosinophils.
• crampy abdominal pain, diarrhoea, distension and
vomiting, often in an atopic or asthmatic patient.
• Peripheral eosinophilia.
• most often involves the stomach, especially the antrum
and the proximal small bowel.
• The clinical and imaging features depend on which
layers of the GI tract wall are involved. Involvement
may be predominantly mucosal, muscular or
subserosal. Many cases are panmural and eosinophilic
ascites is often seen in such cases.

134. • Radiographically
eosinophilic gastritis is
characterized by fold
thickening of the
stomach and small
bowel.
• Antral narrowing and
rigidity with mucosal
nodularity are
frequently seen. CT shows diffuse thickening of the gastric wall
in a patient proven to have eosinophilic
gastroenteritis. No ascites was present.
Symptoms resolved with steroid therapy

135. Corrosive ingestion
• Alkaline substances – oesophagus is usually the target.
• Acids - are more injurious to the stomach and duodenum.
• The consequences of ingesting a corrosive agent follow a
distinct course. First, there is necrosis with sloughing of the
mucosal and submucosal layers. In severe cases, full-thickness
necrosis of the gastric wall may lead to
perforation. In less severe cases, the denuded gastric wall
develops a granulating surface and the formation of
collagen then leads to fibrosis and stricture. The final result
is a deformed, contracted and occasionally obstructed
stomach. The outcome is often total gastrectomy.

136. Radiographic Findings
• depend on the severity of the
chemical insult and the time that
has elapsed since injury.
• Initially, swelling and irregularity
of the gastric mucosa are seen,
occasionally with visible blebs.
• As the mucosa sloughs, barium
flows beneath it and the mucosa
may then be seen as a thin
radiolucent line paralleling the
outline of the stomach.
• After a week or two, fibrotic
contraction of the stomach
becomes evident.
• In severe cases, the lumen of the
stomach may be no larger than
that of the duodenal bulb.
Corrosive gastritis following the ingestion of
household bleach. The distal stomach has
undergone considerable scarring and
contraction in a manner similar to syphilitic
gastritis or linitis plastica.

137. Air in the gastric wall
• Disruption of the gastric mucosa permits air to enter the
gastric wall.
• without an underlying infection - gastric emphysema.
– Causes include corrosive ingestion, gastric ulcer, gastric outlet
obstruction, chronic obstructive pulmonary disease (COPD),
ischaemia and trauma.
• caused by an acute infection (gas forming organisms) -
emphysematous gastritis.
– Escherichia coli and Clostridium welchii.
• Acute panmural infectious gastritis (nongas-forming
organisms) - phlegmonous gastritis.
– alpha-haemolytic streptococcus, Staphylococcus aureus E. coli,
C. welchii and Streptococcus pneumoniae.

138. • The radiological findings in both emphysematous gastritis and
gastric emphysema include thin, curvilinear lines of radiolucent
gas paralleling the gastric wall.
Gastric emphysema on abdominal
radiograph in a patient after
extensive abdominal surgery.
Gastric emphysema.
Note air in the wall of the
stomach together with much
gastric residue. The patient was
vomiting as a result of the tumour
of the distal stomach, causing
gastric outlet obstruction
CT of patient with infectious,
emphysematous gastritis

139. Granulomatous processes
– Crohn’s disease
– Tuberculosis, histoplasmosis and syphilis
– Sarcoidosis
• Ulceration, thick folds and mucosal nodularity
are common features, with antral narrowing
being a late feature of these diseases.

140. Crohn's disease
• Gastroduodenal involvement occurs in up to 20 per cent of
cases
• duodenum alone is more common than the stomach alone
• Radiographic findings
– almost always involve the antrum or antrum and body of the
stomach.
– early (non stenotic) disease - aphthous ulcers, larger discrete
ulcers, thickened and distorted folds and sometimes a nodular
(‘cobble-stoned’) mucosa
– Stenotic phase – scarring and fibrosis narrowing the gastric
antrum and pylorus into a funnel or “rams-horn”shape.
– D/D – other granulomatous diseases, scirrhous gastric
carcinoma

141. Crohn’s Disease of the stomach.
Double Contrast barium study (a) shows distortion of the normal
gastric mucosal pattern with marked nodularity and multiple
aphthous lesions. Note the irregular scalloping affecting the greater
curve, due to active Crohn’s Disease.
Ultrasound (b) and Endoscopic-ultrasound (c) show marked transmural
thickening of the gastric wall. The muscularis propria is intact

142. Crohn’s disease:
stenotic phase with narrowing of the gastric antrum and pylorus

143. Tuberculosis
• Primary tuberculosis of stomach and duodenum is very rare and
usually develops secondary to pulmonary tuberculosis.
• Simultaneous involvement of the duodenum occurs in 10% of
patients.
• There is increased incidence in patients with AIDS.
• The radiological appearances are classified as predominantly
ulcerative or hypertrophic type (Tishler 1979; Agrawal et al. 1999).
• The ulcerative form is more frequent and consists of multiple large
and deep ulcerations, sometimes with antral fistulas.
• In the hypertrophic form, there is thickening of stomach and
duodenal folds which can lead to pyloric stenosis and gastric outlet
obstruction. A narrowed antrum can mimic a linitis plastica
appearance.
• There is usually extensive lymph node involvement in the adjacent
areas (Tishler 1979; Agrawal et al. 1999).

144. Gastroduodenal tuberculosis:
• Double-contrast barium meal
showing destruction of the pre-pyloric
region, pylorus, and first
part of the duodenum due to
intramural ulcers and fibrosis

145. Other granulomatous diseases
• Sarcoidosis and syphilis
have identical
appearances on
conventional barium
studies, both ulcerative
and hypertrophic
Gastric sarcoidosis:
Double-contrast barium meal shows nodular
thickening of the gastric rugae in a patient with
sarcoidosis

146. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

147. Infectious gastritis
• H. pylori gastritis
– the most common infection.
• Monilia
– the presence of severe oesophageal disease.
– Prominent aphthous ulceration

148. • In immunocompromised patients,
– Cytomegalovirus
• Deep ulceration, and even fistulization to adjacent structures may
be seen with.
– Cryptosporidium
• primarily affects the small bowel causing severe diarrhoea and
thick, small bowel folds. It rarely involves the stomach but has
been shown to cause deep ulcers, antral narrowing and rigidity.
– Strongyloides
• affects the upper gastrointestinal tract, duodenum and proximal
small bowel with thickened, effaced folds and narrowing. In
advanced cases, the stomach may be narrowed and have
thickened folds.

149. Gastric abscess
• Rare condition representing a localized form of
suppurative gastritis.
• Predispositions:
– alcoholism, immunosuppression, diabetes, HIV, old
age, foreign body.
• CT findings:
– Localized mural thickening within stomach wall or
focal mass with heterogeneous enhancement.
– Fluid and air may be seen within the mass. Adjacent
inflammatory stranding may be present.

150. Gastric abscess
• 65-year-old AIDS patient
with intramural gastric
and liver abscess.
• CT reveals
heterogeneously
enhancing masses in the
wall of the stomach and
liver .
• Biopsy revealed abscess
in both the liver and
stomach with gram
negative organisms.

151. • Perforated peptic ulcer
with multiple gastric
and perigastric
abscesses.
• CT reveals multiple
peripherally enhancing
abscesses in the gastric
and perigastric location
along the greater
curvature of the
stomach.

152. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

153. Positional abnormalities
• Several peritoneal reflections, permitting it
relative mobility
• These include the gastrohepatic ligament (lesser
omentum), the gastrosplenic ligament and the
gastrocolic ligament, which is part of the greater
omentum.
• The oesophagogastric junction passing through
the oesophageal hiatus of the diaphragm
normally fixes the proximal stomach while the
distal stomach is anchored at the pyloroduodenal
junction.

154. Hiatus hernia
• most common positional abnormality
• the stomach herniates into the chest through the
oesophageal hiatus when there is widening of the
opening between the diaphragmatic crura.
• The prevalence of hiatal hernia increases with age
and is present in over 50 per cent of the aged
population.
• Most hiatal hernias are small, involving a
protrusion of a part of the gastric fundus at least
1.5–2 cm above the diaphragm. At the opposite
extreme the entire stomach may be intrathoracic.

155. Sliding hiatal hernias
• most common type of hiatal hernia.
• the gastro-oesophageal junction slides proximally
through the diaphragmatic hiatus to assume an
intrathoracic location.
• Small or moderate-sized hiatal hernias are often
reducible, changing in size and configuration
during barium evaluation.
• They are best demonstrated with the patient
recumbent in the right anterior oblique position.
• Sliding hiatal hernias are often accompanied by
gastro-oesophageal reflux and reflux oesophagitis

156. (A) Sliding hiatal hernia. Chest X-ray shows a large air collection
overlying the heart shadow.
(B) CT shows a large part of the barium-filled stomach is in the chest.
(C) In this patient, an upper GI exam shows that the gastric fundus and
most of the body of the stomach is intrathoracic

157. Paraoesophageal hernias
• the gastro-oesophageal junction is in its
normal position below the diaphragm.
• The proximal stomach herniates through the
oesophageal hiatus usually to the left of the
distal oesophagus in the posterior
mediastinum.
• more prone to incarceration and obstruction
than a sliding hernia.

158. Traumatic diaphragmatic hernias
• result from a tear in the diaphragm either from a direct
penetrating injury or from a sudden increase in intra-abdominal
pressure during blunt trauma.
• almost always on the left side.
• Herniation may occur immediately after trauma or may
be delayed by many years.
• Diagnosis is often difficult both due to lack of
specificity of symptoms and because it is often
confused with simple elevation of the hemidiaphragm.
• On barium studies the recognition of the gastric hernia
lateral to the normal oesophageal hiatus is crucial.
• CT is also often helpful in diagnosis.

159. Gastric volvulus
• Occurs when the stomach twists on itself between the
points of its normal anatomical fixation.
• It may cause gastric outlet obstruction or vascular
compromise resulting in a surgical emergency.
• Most common in the elderly but may occur at any age.
• When acute and obstructing
– Abdominal pain
– Attempts to vomit without results
– Inability to pass an NG tube
• Together, these three findings comprise the Borchardt triad
which is diagnostic of acute volvulus (in 70% of cases)

160. Gastric volvulus is often divided into two types depending
on the plane of torsion.

161. Mesentero-axial volvulus
The antrum of the stomach has herniated into the chest alongside the oesophagus.
Endoscopy was described as difficult and could not be completed, but the cause of
the problems encountered was not understood

162. Radiographic signs
• upright plain radiograph:
– a double air–fluid level of the stomach in the
mediastinum and upper abdomen
• barium studies:
– the stomach may be inverted with the greater
curvature above the lesser curvature, or the
pylorus above the cardia and the torsed area
identified as the source of the obstruction

163. EXTRINSIC IMPRESSIONS
• Organomegaly or masses in upper abdominal
organs may displace or cause extrinsic
impressions on the stomach.
• These most commonly involve the spleen, left
lobe of the liver and pancreas.
• These processes may be deduced from the
position and configuration of the compression on
upper gastrointestinal examination, but are
primarily evaluated by computed tomography
(CT) or ultrasound (US).

164. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscelleous
• Post surgical
• Neoplastic

165. Infarction
• Etiologies:
– arterial thrombosis,
herniation /volvulus, caustic
ingestion, therapeutic
embolizations, post-op.
• CT features:
– Wall thickening with non-enhancing
wall.
– Intramural gas and
perforation may be present.
– Associated findings may
include other visceral
infarctions and portal venous
gas.
Acute gastric and small bowel infarction in a
62-year -old woman with heart failure and
atrial fibrillation.
CT reveals thickened non-enhancing gastric
wall with pneumatosis . The small bowel is
fluid distended and dilated with non-enhancing
walls with extensive pneumatosis

166. Herniation with iscemia
Perforation and ischemia of the stomach contained in an epigastric hernia. The distal
stomach is seen within the hernia sac and is focally dilated. There is free fluid and air
within the peritoneal cavity. Caudal sections reveal gastric perforation.

167. Varices
• patients with portal hypertension and oesophageal varices.
• Gastric veins provide one of the collateral pathways when there is obstruction of
the portal vein.
• The presence of gastric varices in the absence of oesophageal varices is a sign of
splenic vein thrombosis most often associated with pancreatitis or pancreatic
carcinoma.
• often seen in the fundus around the oesophagogastric junction sometimes
involving the proximal body.
• They appear as widened, effaceable polypoid folds. They may be nodular-appearing,
‘grape-like’ or appear mass-like, in which case they may mimic gastric
cancer. Rarely they occur in the antrum without fundal involvement.
• Transabdominal and endoscopic US are important techniques for definitive
diagnosis of gastric varices.
• D/D: for thick polypoid gastric folds includes hypertrophic gastritis, Ménétrier's
disease and lymphoma.

168. • Multiple nodular and
curved submucosal
masses in the fundus
are a common
appearance of gastric
varices.

169. Gastric varices.
The precontrast images (a, b) demonstrate masses indenting the fundus of the stomach
which on (a) in particular could be confused with a fundal tumour.
The nature of the abnormality becomes clear following contrast administration (c)

170. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma / Iatrogenic
• Foreign body
• Miscelleous
• Post surgical
• Neoplastic

172. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscelleous
• Post surgical
• Neoplastic

173. Bezoars
• A bezoar is a mass of foreign matter
composed of retained ingested material in the
stomach and small bowel.
• They can be classified into two main types:
phytobezoars and trichobezoars

174. Trichobezoars
• It consist of large quantity of ingested hair firmly matted
together, forming an intraluminal cast in the stomach and
frequently extending into the duodenum (Choi and Kang 1988).
• These are found most commonly in young psychiatric
patients, almost exclusively females.
• Radiological features of bezoars on contrast studies are
very distinctive, allowing a more confident diagnosis with
no need for further imaging.
• It appears as a large, filling defect with poor barium coating
due to uneven filling of the interstices.
• There is no constant site of attachment with the stomach
wall (Szemes and Amberg 1968; Choi and Kang 1988).

175. Trichobezoar:
double-contrast barium meal showing a large
filling defect occupying the whole lumen of the
stomach and photograph of the removed
trichobezoar

176. Phytobezoars
• caused by:
– ingestion of poorly digested
fibres, most commonly orange,
persimmon skin, and seeds.
• Predisposing conditions
include:
– previous gastric surgery such as
Billroth I and II operations,
especially if complemented by
a vagotomy procedure (Szemes and
Amberg 1968). These may lead to
decreased motility and
digestive ability of the
remaining portion of the
stomach, thus impairing gastric
emptying.
Phytobezoar: double-contrast barium meal
shows a phytobezoar in a patient with previous
partial gastrectomy

179. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

180. Hypertrophic Pyloric Stenosis
• congenital disorder diagnosed in infancy.
• Presentation in adults occasionally occurs.
• hypertrophy and hyperplasia of the circular muscle
with some contribution by the longitudinal muscle. The
hypertrophied muscle lengthens and narrows the
pyloric channel.
• Radiographically, there is lengthening of the pyloric
channel (2–4 cm long) with smooth symmetrical
narrowing. The hypertrophied muscle bulges
retrograde into the antrum, creating a ‘shoulder’.
• In infants US generally provides the definitive
diagnosis.

183. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical stomach
• Neoplastic

184. SURGICAL APPEARANCES
• In the past partial gastrectomy was often performed for PUD.
• This consists of antrectomy, vagotomy and creation of either a
gastroduodenostomy (Billroth I) or a gastrojejunostomy (Billroth II).
• More recently gastric bypass surgery has replaced the Billroth II for
weight reduction.
• On CT the gastric pouch and the gastric remnant are easily
visualized as well as the type of gastric bypass, whether it is a
retrocolic, retrogastric or antecolic, antegastric bypass.
• Complications such as obstruction or extravasation are also seen
readily on CT.
• The most common method of following up a bypass patient is a
single-contrast upper GI study, usually 1–2 days postoperatively.

185. The stomach is foreshortened
due to an antrectomy with a
gastroduodenostomy. This is a
Billroth I - type anastomosis
Vagotomy, partial gastrectomy, and
Billroth-ll anastomosis. Note the
metallic clip at the esophagogastric
junction.

186. • Pyloroplasty
– widen the lumen of the pylorus and facilitate
gastric emptying.
– frequently combined with a vagotomy.
– the normal pyloric contours are lost, and a pouch-like
deformity may be observed.
• Fundoplication procedures
– To prevent gastro-oesophageal reflux and produce
a characteristic deformity of the gastric cardia.

187. COMPLICATIONS OF GASTRIC SURGERY
• Submucosal haemorrhage
– may lead to outlet obstruction
– usually self-limited and subsides within 10 days.
• Leakage from the duodenal stump or anastomosis after gastrojejunostomy
– most common cause of death during the postoperative period.
– The incidence of this complication is 1–5 per cent, with a mortality rate of 40–
50 per cent.
– Stump leakage usually occurs during the first 2 weeks after surgery.
• Ischaemia of the stomach leading to necrosis and fistula formation
– significant morality rate.
• Leakage
- diagnosed after ingestion of water-soluble contrast material.
• Persistent severe diarrhoea caused by inadvertent gastroileostomy instead of
gastrojejunostomy also is best diagnosed by upper gastrointestinal examination

188. COMPLICATIONS OF GASTRIC SURGERY
• Marginal ulcerations
– 3–10 per cent of patients who have been operated on
for PUD.
– within the first 2 cm of anastomosis on the jejunal side
– usually caused by inadequate vagotomy.

189. COMPLICATIONS OF GASTRIC SURGERY
• Afferent loop obstruction
– may be acute or chronic.
– This is usually caused by herniation of the afferent loop through a
surgically created defect behind the gastroenteric anastomosis.
– Chronic afferent loop obstruction occurs because of preferential
gastric emptying into the afferent loop .
– Patients present with intermittent bilious vomiting, weight loss,
malabsorptions and steatorrhoea.
– Preferential filling of the afferent loop is seen on upper
gastrointestinal examination.
– Barium is retained within the afferent loop on delayed films, and
regurgitation of contrast material into the stomach from the afferent
loop may be recognized.
– This syndrome may be associated with a very long afferent loop.

190. COMPLICATIONS OF GASTRIC SURGERY
• Efferent loop obstruction
– usually caused by spasm and inflammation.
– manifested between the fifth and tenth
postoperative days,
– usually a self-limited phenomenon not requiring
specific treatment.
– Upper gastrointestinal examination reveals
delayed transit in the efferent loop

191. COMPLICATIONS OF GASTRIC SURGERY
• Prolapse and intussusception may occur at
the anastomosis postoperatively.
– Jejunogastric intussusception is the most common
abnormality of this type.
– Either the afferent or the efferent loop may be
involved, although the efferent loop is involved in
75 per cent of cases

192. COMPLICATIONS OF GASTRIC SURGERY
• Bezoars
– after Billroth I and II
procedures, especially
when these are
accompanied by
vagotomies.
– Gastric bezoars are more
common after the Billroth I
procedure, and those in
the small bowel after
Billroth II anastomoses.
– usually phytobezoars
related to an improper diet
postoperatively
Gastric bezoar. Large mass in stomach –
solidified retained ingested fibrous material
mixed with air in the patient after a Billroth II
anastomosis

193. COMPLICATIONS OF GASTRIC
SURGERY
• Primary gastric
carcinoma
– occasionally develops in
the gastric remnant
– Incidence - 0.3–11 per
cent.
– approximately 1 per cent
of all gastric cancers.
– the patients have a
relatively high incidence
of atrophic gastritis.
– Billroth II > Billroth I
Wall thickening at the anastomosis site
Post Bilroth II anastomosis

194. • On upper gastrointestinal
examination, these tumours
may have several appearances.
• They may appear as a lack of
distensibility of the gastric
remnant.
• Obstruction, either at the
stoma or at the gastro-oesophageal
junction, may be
seen.
• A pattern of enlarged rugae
with intraluminal masses or
gastric ulcer formation may
also be seen.
Gastric cancer after Billroth II anastomosis.
There is narrowing, irregularity and lack of
distensibility around the anastomosis

195. Classification
• Congenital
• Inflammatory
• Infectious
• Positional
• Vascular
• Trauma
• Foreign body
• Miscellaneous
• Post surgical
• Neoplastic

196. Benign Tumors
• Polyps
– Non neoplastic
• Hyperplastic polyps
• Hamartomatous polyps
• Retention polyps
– Neoplastic
• Adenomatous polyps
• Villous polyps
• Lipoma
• Neural tumors
• Mesenchymal tumors

197. Gastric Polyps
• Gastric polyps are the most common benign
gastric tumours.

199. • They can be broadly divided into non-neoplastic
and neoplastic polyps.
• Non-neoplastic polyps include:
– Hyperplastic, hamartomatous, and retention
polyps
• Neoplastic polyps include
– Adenomatous and villous polyps.

200. Hyperplastic polyps
• most common benign neoplasms of the
stomach.
• NOT considered to have malignant potential
• but do occur more commonly in patients who
have other risk factors for developing gastric
malignancy, such as atrophic gastritis, and in
patients with gastric resections and bile reflux
gastritis.

201. • Radiographically,
hyperplastic polyps are
round, smooth sessile
lesions.
• They are usually
multiple and of uniform
size (< 1 cm).
• They are most common
in the fundus and body
of the stomach.
Hyperplastic polyps in the body of the stomach
– small, sessile and uniform in size

202. Multiple hyperplastic polyps:
a Double-contrast barium meal showing multiple filling defects in the stomach due
to hyperplastic polyps and (b) endoscopic view of hyperplastic polyps in a different
patient

204. Fundic gland polyps
• variant of hyperplastic
polyps believed to be
hyperplastic fundal
glands
• not found in the
antrum.
• These are identified in
up to 40 per cent of
patients with familial
adenomatous polyposis
coli. Fundic gland polyps morphologically identical
to hyperplastic polyps predominate in the
fundus as shown in this patient with familial
adenomatosis coli

205. Non neoplastic polyps
• Hamartomatous polyps
are sessile or
pedunculated, usually
less than 2 cm in
diameter and are
associated with Peutz-
Jeghers syndrome.
• Retention or
inflammatory polyps
are very rare such as
associated with
Cronkhite-Canada
syndrome.

206. Adenoma
• usually solitary
• can be broad base or
pedunculate
• have a lobulated
appearance with a smooth
or irregular contour.
• They are most commonly
found in the antrum.
• On double-contrast barium
meal they have smooth
circular outline, with the
stalk seen en face overlying
the head of the polyp – the
“Mexican hat sign”
Gastric adenoma:
Double-contrast barium meal shows an
adenoma as seen en face – “Mexican hat sign”

207. (A) Mexican hat.
(B) Radiograph of an upper gastrointestinal series demonstrates a
pedunculated gastric polyp demonstrating a close resemblance to a
Mexican hat.

208. Adenomatous polyps
• Adenomatous polyps
coexist with gastric
carcinoma in 35% of
cases and malignancy is
detected histologically
in 50% of adenomas
larger than 2 cm
(Tomasulo 1971).
Biopsy-proven adenomatous polyp in the
gastric antrum (arrow)

209. Villous polyps
• Villous polyps carry a very high risk for
malignancy.
• They are characterised by numerous frond-like
projections which give them a typical bubbly
appearance on double-contrast barium meal.

210. Gastric lipoma
• Gastric lipoma is rare
and usually appears as a
smooth submucosal
mass (Maderal et al. 1984).
Gastric lipoma: Double-contrast barium meal
shows a perfectly smooth submucosal mass
due to a lipoma

211. Neural Tumours
• 5–10% of benign gastric
tumours (Hoare and Elkington 1976).
• majority are nerve sheath
tumours (neurinomas,
schwannomas or
neuromas).
• Mostly benign, but
occasional sarcomatous
changes
• CT - submucosal masses
(with or without ulceration)
that are indistinguishable
from other mesenchymal
tumours
Biopsy-proven schwannoma.
There is a submucosal soft tissue mass that
shows only minor enhancement but a
preserved and strongly enhancing mucosa
(arrow). Note that the perigastric fat plane
around the tumour is clear

212. Mesenchymal lesions
• second most common type of polypoid lesion in
the stomach after hyperplastic polyps.
• Mesenchymal tumours of the gastrointestinal
tract are referred to as gastrointestinal stromal
tumours (GISTs) and include most lesions
previously designated leiomyoma,
leiomyoblastoma and leiomyosarcoma.
• Approximately 70 per cent of GISTs occur in the
stomach and most (70–90 per cent) are benign.

213. • Submucosal tumours, including GISTs and true
leiomyomas account for about 90 per cent of all
the gastric mesenchymal tumours.
• Most of the tumours are small and are discovered
incidentally during evaluation for unrelated
problems.
• Ulceration becomes more common as the lesions
grow to >2 cm in size and symptoms, including
epigastric pain and gastrointestinal bleeding,
become more common.

215. • Radiographically the tumours appear
as discrete submucosal masses
typified by a smooth mucosal surface
with borders forming right or slightly
obtuse angles to the adjacent
mucosa.
• En face, the preservation of a normal
areae gastricae pattern over the mass
confirms the presence of normal
mucosa and the extramucosal
location of tumour.
• When there is ulceration it is usually
seen as a central collection of barium
in a smooth or slightly lobulated mass.
This is sometimes called a ‘target’ or
‘bulls-eye’ lesion.
• Leiomyomas occasionally contain
coarse mottled calcifications
Leiomyoma adjacent to the gastro-oesophageal
junction shown on CT as a
smooth soft tissue mass in the contrast-filled
stomach

216. Leiomyoma of the stomach.
Double Contrast barium study (a) shows a well delineated smooth mass arising from the lesser
curve of the stomach.
Endoscopic-ultrasound (b) demonstrates a massive lesion which does not penetrate through the
gastric wall. Biopsy revealed a benign leiomyoma

217. • 15 per cent – grow predominantly outside the
stomach (exogastric)
• < 5 per cent of cases – have an intra- and
extraluminal growth pattern (‘dumbbell’).
• Occasionally they are pedunculated
– may obstruct the pylorus or duodenum or
– act as the lead point of an intussusception.

218. An endogastric GIST arising from the posterior
wall of the stomach. Note the intraluminal
position with relatively acute angles to the
adjacent gastric wall, as well as the
heterogeneous attenuation
An exogastric GIST arising from the posterior
wall of the stomach.
Note the more obtuse angle it forms with the
body of the stomach and again a
heterogeneous attenuation pattern. The size of
this lesion together with the lack of definition
of its margin suggest that this is frankly
malignant

219. Malignancy??
• 10 per cent are malignant.
• Unfortunately, the prediction of malignancy is difficult even by
histological criteria.
• GISTs are classified by their estimated risk of recurrence and
metastasis into low- or high-risk categories.
• Imaging findings contribute importantly to the assessment of risk of
malignancy.
• A favourable prognosis is associated with
– tumour size <5 cm and
– lack of infiltration into adjacent organs.
– Gastric GISTs > distal GI tract GISTs
– low mitotic index (<2/10 high-power fields),
– low proliferation index and
– DNA-diploidy in the G-2 peak by flow cytometry.

221. MALIGNANT NEOPLASMS
• Gastric carcinoma and lymphoma are the
most common malignant neoplasms of the
stomach.
• Each of these has a variable radiographic
appearance, with some overlap of
radiographic signs.
• Other malignant neoplasms are considerably
less common.

222. Gastric Carcinoma
• more prevalent in Japan than elsewhere.
• A difference in diet is the most strongly
implicated reason for this occurrence
• most gastric cancers are detected at an advanced
stage due to the nonspecific and insidious nature
of symptoms.
• The incidence of gastric cardia tumours has
increased while the incidence elsewhere in the
stomach has decreased or remained stable

223. Early gastric carcinoma
• defined as gastric carcinoma that is limited to
the mucosa and submucosa with or without
associated lymphadenopathy (Gore et al. 1997).

224. • At double-contrast
barium meal early gastric
cancer appears as:
– an elevated polypoid
lesion (type I),
– superficial plaque-like
lesion (type II), or
– shallow irregular ulcer with
adjacent nodular mucosa
and associated amputation
of radiating folds (type III)
(Gold et al. 1984).

226. Early Gastric Cancer.
Double Contrast barium study (a) shows slight distortion of normal mucosal folds on the
posterior wall of the antrum of the stomach.
Endoscopy (b) demonstrates the non-depressed lesion, with distortion of the normal gastric
mucosal pattern. Histopathology confirmed early gastric cancer

227. Advanced gastric carcinoma
• Tumours most frequently present as large,
irregular masses that may or may not be
ulcerated.

228. • The margins of the masses
may exhibit a shelf, and form
an acute angle with the gastric
wall, indicating the mucosal
origin of the tumour.
• This may become less obvious
as the tumour enlarges.
• As the mucosa is primarily
involved by the tumour, the
surface is generally irregular.
• When the antrum is primarily
involved by tumour, it may be
severely narrowed or
obstructed.
Large circumferential mass in the body of the
stomach with a shelf at the proximal margin
sharply demarcating the cancer from the
proximal stomach.

229. Gastric carcinomas may demonstrate several forms at CT:
a thick walled ulcer polypoid mass
infiltration of the gastric wall
with reduced distension and
loss of mucosal detail

230. • Sometimes, the stomach
can be diffusely infiltrated
by a scirrhous tumour
resulting in a linitis plastica
or “leather bottle”
appearance (Low et al. 1994; Gore et
al. 1997).
Gastric carcinoma:
Infiltrative gastric carcinoma producing
a linitis plastica or “leather bottle appearance”

231. Scirrhous gastric carcinoma. Gastroscopy
revealed irregular
mucosal folds in the body of the stomach (a).
Biopsies were negative
and follow-up examinations with a barium
meal (b) and ultrasound (c)
revealed narrowing of the lumen, typical
irregular folds, and a thickened gastric wall

232. Linitis plastica
• descriptive term for a tumour of the stomach,
usually a carcinoma, which is diffusely
infiltrating with considerable fibrosis.
• Radiographically this usually appears as a
narrowed, rigid stomach.

234. scirrhous carcinoma with linitis plastica
appearance.
Poor distensibility of the stomach is shown
on the barium study (a) and wall thickening
confirmed by CT

235. • Linitis plastica
appearance caused by
eosinophilic
gastroenteritis.
• The clue to the
diagnosis relates to the
infiltration extending
into the duodenum,
although this was not
appreciated at
endoscopy

236. Staging of Gastric Carcinoma
• The TNM classification system
• Two important factors influencing survival in
resectable gastric cancer are
– depth of invasion and
– regional lymph node involvement.
• Although such imaging studies such as the
double-contrast upper GI, CT and MRI are useful
in examining a patient with suspected gastric
carcinoma, and possibly detecting lymph node
involvement, their usefulness remains limited for
staging.

237. Preoperative tumour staging
• most commonly performed using CT, although endoscopic
US is used in some centres primarily for evaluating the
depth of gastric wall invasion.
• In a patient with nonspecific abdominal symptoms, the
gastric neoplasm may first be detected on a ‘routine’ CT.
• On CT, gastric cancer may present as
– focal wall thickening with or without ulceration,
– mass or
– diffuse wall thickening.
• In a well-distended stomach, a wall thickness of >1 cm is
considered abnormal.
• Tumours may exhibit abnormal contrast enhancement of
the gastric wall and loss of the normal multilayered wall
pattern.

238. • Using CT, the tumour may not only be diagnosed, but
may also be staged.
• Wall thickness, the presence or absence of regional
lymphadenopathy, adenopathy in the left gastric, porta
hepatis and peripancreatic area and the presence or
absence of liver metastases can be evaluated.
• The pancreas, left lobe of the liver, spleen and
transverse colon may all be involved by direct
extension of tumour.
• Distant or diffuse intraperitoneal metastatic disease
may also be detected.

239. TNM Staging

241. • Advanced gastric cancer (pT2).
• Coronal reformation shows focal wall
thickening of the antrum with marked
enhancement of the mucosal layer
(arrows). At histology, the outer layers of
the muscularis propria were intact, whereas
the inner layers were infi ltrated. The subtle
irregularities of the mucosal surface
correspond to ulceration at histology. Note
the clear fat plane around the tumour.
• Large carcinoma at the lesser curvature.
Note that there is an area with irregular
delineation of the tumour from the
surrounding fat (arrowhead), which
corresponds to a desmoplastic reaction at
histology. There are two slightly
hyperenhancing lymph nodes adjacent to
each other (arrow); both proved to be
metastases positive at histology.

242. • Advanced gastric cancer (pT3).
• A large polypoid carcinoma with gross
infiltration of the perigastric fatty tissue
(arrows).
• Oblique coronal reformation tilted
posteriorly to display the corpus and fundus
of the stomach and distal oesophagus.
There is a large tumour (T) that protrudes
from the posterior wall into the lumen and
appears as a filling defect within the water-filled
stomach. Note the increased density
stranding in the perigastric fat (arrow) and
the oval lymph node that proved to be
hyperplastic at histology (arrowhead)

243. • Advanced gastric cancer (pT4).
• Advanced gastric cancer of the posterior
wall of the body that infiltrates the tail of
the pancreas (arrow).
• Coronal reformation of the posterior
portions of the abdomen. Large gastric
cancer with obliteration of the fat plane and
thickening of the colonic wall (arrow). At
histology, the transverse colon was
infiltrated.

244. N STAGING
Regional lymph nodes are considered involved when the short-axis diameter is
>6 mm for the perigastric lymph nodes and
>8 mm for the extraperigastric lymph nodes
Other criteria for malignant involvement include:
Nearly round shape (L/T ratio <1.5)
Fatty hilum eccentric or missing
Strong or heterogeneous enhancement

245. M Staging

246. Gastric lymphoma
• stomach – most frequent site of
gastrointestinal lymphoma.
• Mostly of the non-Hodgkin's type.
• Gastric involvement may be primary, due to
direct extension from involved lymph nodes,
or part of generalized disease.
• There is no anatomic predilection but when
the antrum is involved duodenum is often
affected.

247. MALT lymphoma
• type of non-Hodgkin's lymphoma that occurs in the lung,
thyroid and salivary glands and intestine, but the stomach
is by far the most common site.
• Normally, there is no lymphoid tissue in the gastric mucosa.
• Helicobacter pylori, the only common bacterial antigen in
the stomach, results in an accumulation of gastric mucosa-associated
lymphoid tissue.
• Double-contrast upper gastrointestinal studies demonstrate
rounded, often confluent nodules of varying size which can
be difficult to distinguish from gastritis or leukaemic
infiltration (Levine et al. 1996; Yoo et al. 1998; Brown et al. 2000).
• Depressed lesions and thickened fold may also be seen

249. Gastric MALT lymphoma showing marked thickening of the posterior wall of the stomach
(a). Note the bilateral shrunken kidneys in this renal transplant patient.
There is also marked extranodal lymphadenopathy in the region of the omentum,
suggesting that the underlying condition is more likely to be high-grade (b)

250. Primary Gastric Lymphoma
• no typical radiographic appearance, and may
mimic any of the appearances of gastric
carcinoma.
• At double-contrast barium meal gastric
lymphoma may demonstrate
– an infiltrative appearance with thickened broad
tortuous mucosal folds,
– a circumscribed mass growing inside or outside the
lumen of the stomach, or
– large irregular ulcers (Sherrick et al. 1965; Menuck 1976).

251. • There are four gross pathological types of gastric
lymphoma (Fischback et al. 1992):
– Infiltrative gastric lymphomas manifest as a focal or
diffuse enlargement of rugal folds due to submucosal
spread of tumour (Fig. 6.2.11a).
– One or more ulcerated lesions characterize ulcerative
gastric lymphoma (Fig. 6.2.11b).
– Polypoid gastric lymphomas are characterized by
intraluminal masses that may simulate polypoid
carcinomas (Fig. 6.2.11c).
– Multiple submucosal nodules ranging in size between
several millimetres and several centimetres characterize
the nodular form of gastric lymphoma (Fig. 6.2.11d).

252. Infiltrative Ulcerative
Polypoid Nodular

253. Lymphoma v/s Carcinoma
• CT may be helpful in differentiating gastric
lymphoma from carcinoma, although at times
the appearance of these two entities may be
identical.
• Direct spread of disease or invasion of the
stomach from enlarged regional lymph nodes
may be observed, and may sometimes by
helpful in differentiating these two processes.

254. Gastric carcinoma Lymphoma
Wall thickening Less thick, mean = 1.8cm
homogeneously thick
Very thick, mean = 4 cm
focally thick
Perigastric fat planes May be obliterated Usually preserved
Regional adenopathy Common Common
Extent of adenopathy Does not extend below renal vein May extend below level
Less bulky Large bulky nodes
Extent Does not commonly involve
duodenum
May involve duodenum

255. Tumours of mesenchymal origin
(gastrointestinal stromal tumours)
• Most malignant mesenchymal tumours seen in the stomach are
malignant GIST tumours many of which are called
leiomyosarcomas.
• They are indistinguishable from their benign counterparts
radiographically, and frequently histologically, except for size.
• If the size of the mass is >5 cm, malignancy should be strongly
considered.
• As a result of the large size of these tumours, they frequently
outgrow their blood supply and ulcerations are therefore common.
• Tumours may arise from any of the mesenchymal elements of the
gastric wall, including the neural elements.
• These are all radiographically indistinguishable from one another.

257. GIST response to Glivec therapy.
The initial CT demonstrates a huge
predominately exophytic GIST arising from the
greater curve of the stomach (a). Note the
metastasis in the liver.
Following three months of Glivec therapy,
there has been dramatic reduction in the size
of the main tumour and it is of lower
attenuation (b). However, there has been
relatively little change in the appearance of
the metastasis

258. Metastatic Disease
• They may result from
– direct spread such as from a carcinoma of the
pancreas or kidney or colon or
– from a haematogenous route.

260. • The most common primary tumours that
metastasize to the stomach are breast,
malignant melanoma and lung.
• Blood-borne metastases to the stomach
appear radiographically as gastric wall lesions.
• Initially these can be seen as small intramural
masses, usually multiple, that are
indistinguishable from benign disease.

261. Metastasis to the stomach.
Double Contrast and Single Contrast barium studies
(a) demonstrate a villous type tumour arising from the
lesser curve aspect of the antrum, confirmed at
endoscopy
(b). Biopsy revealed a metastasis from breast cancer

262. • These may contain central ulcerations, having
a bulls-eye appearance.
– most frequently seen in metastatic melanoma,
lymphoma and Kaposi's sarcoma.
• As these lesions grow, the aetiology becomes
apparent.
• Breast carcinoma may produce a linitis
plastica-type appearance, indistinguishable
from primary gastric carcinoma.

265. Angiography of the Stomach
• DSA to examine coeliac axis and SMA
• Bowel should be paralyzed
• Adequate breath hold

266. Indications
• Gastrointestinal Bleeding
• Tumors

267. Gastrointestinal Bleeding
• Commonest indication
• Endoscopy – primary indication and
performed prior to angiography

268. • Active bleeding is
identified
angiographically when
contrast medium
extravasates into the
bowel lumen.
• This finding may be
absent if the bleeding is
intermittent and other
more indirect
angiographic signs such
as
– an aneurysm,
– early venous return,
– vascular irregularity or
truncation should be
sought.

269. • For many years it has
been accepted that the
identification of a
bleeding source requires
a blood loss at a rate of
0.5 ml/min (Nusbaum and
Baum 1963), but in general
the chance of localising
the site of bleeding is
greater with a higher rate
of blood loss.
• The timing of
angiography is evidently
critical and a good ‘rule of
thumb’ is that
– the patient’s pulse should
be greater than 100
beats/min and
– the systolic blood pressure
less than 100 mmHg, to
maximise the chance of
localisation.

270. • The most frequent causes of gastric bleeding are:
– peptic ulcers, followed by
– Iatrogenic causes, e.g. following biopsy or surgery, and
– aneurysms.
• The role of angiography in the upper
gastrointestinal tract is focussed more on therapy
by embolization than purely diagnosis,
particularly in elderly patients with high co-morbidity
who are poor surgical candidates

271. Aneurysms
• Visceral aneurysms are uncommon and most
frequently involve the splenic artery.
• Contrast enhanced CT is usually performed
and this may reveal a haematoma and
sometimes the aneurysm itself, which is a
useful guide for subsequent angiography.

273. Tumours
• Embolization are useful in inoperable primary
leiomyosarcomas, which can cause severe
bleeding, and large invading pancreatic
neuroendocrine tumours.

274. Zollinger-Ellinson Syndrome
• Angiography is indicated for preoperative localisation
of the tumour, which can be single or multiple.
• preoperative localisation of the tumour
• Historically, the sensitivity of angiographic localisation
has been increased by the use of intra-arterial injection
of secretin (Doppman et al. 1990).
• This has now largely been superseded by using calcium
gluconate, which has been demonstrated to be a highly
sensitive and specific alternative (Turner et al. 2002).

275. RADIOLOGICAL INTERVENTION IN
THE STOMACH

276. Introduction
• Until recently interventional procedures for
lesions of the gastro-oesophageal junction,
the stomach and the duodenum have been
the domain of the endoscopist. However,
difficult or failed endoscopic cases are
frequently referred for radiological
management.

277. Patient Preparation
• Ensure adequate hydration to maintain renal
function, and
• Anaemia and clotting abnormalities need to
be corrected.
– haemoglobin > 100 g/l,
– platelets > 50.000/ μl,
– PT-ratio (international normalised ratio, INR) and
– APTT ratio ≤ 1.3.
• Proper assessment of sedation risk,

278. The Pre Operative Stomach
• Main indication: gastric outlet obstruction
• Stent insertion is cheaper and results in
quicker recovery than open gastro-jejunostomy
(maetani et al. 2004; mittal et al.
2004)
• The proximal margin of the lesion is assessed
either endoscopically or fluoroscopically.
• Need for fluoroscopy is imperative to assess
the distal margin of the obstruction

279. Obstructing pancreatic tumour: Fluoroscopic stent placement in prone position.
Injection of contrast shows an irregular stricture at the pylorus (arrow).
b The stricture is crossed with a looped, stiff hydrophilic wire Aqualiner

280. c Injection of air and contrast shows a possible further stricture in D2 (arrow).
d The hydrophilic wire is exchanged for a heavy duty wire, note the junction of the
flexible wire tip with the stiff shaft (arrow). The stent delivery system (arrowheads) is
positioned, allowing for stent shortening deployment.

281. e A Niti-S stent immediately after deployment. The stent is in excellent position, with
an initially distorted appearance.
f After 24h the nitinol skeleton has regained its original configuration (patient supine)

282. Obstruction of the gastric outlet: using a doubled- up wire is the
safest way to traverse a stricture, avoiding perforation as well as
exiting through the sides of an existing stent.

283. The Post-Operative Stomach
• The procedure for stenting anastomotic
tumour recurrence after Billroth I
gastrectomy is exactly as described in the
native stomach.
• Similarly tumour recurrence after Polya
(Billroth II) gastrectomy can be treated with
stenting of the gastro-enterostomy

284. • a–d. Recurrent tumour
obstructing the efferent
loop of a Polya (Billroth 2)
gastro-jejunostomy.
• The stricture (arrowheads)
is easily identified, a
through-the- scope delivery
system passed (arrow) and
an uncovered Hanaro
nitinol stent deployed.
Initial limited expansion will
increase over the space of
several days

285. Gastrostomy
• Percutaneous gastrostomy for feeding support is a
procedure for which there has been enormous
demand since it was first described in children in
1980 (Gauderer et al. 1980).
• Before this, gastrostomy was a surgical procedure,
which required opening the abdomen and stomach
in order to place the feeding tube.

286. Percutaneous Endoscopic Gastrostomy
(PEG)
• The quickest and simplest way to place a
gastrostomy is with endoscopic support.
• The endoscope is passed into the stomach,
which is inflated with air and a point in the
body or antrum is chosen for entry.

287. • occasionally fails because of
– unsuccessful endoscopic access or
– inability to determine a safe point of puncture
(Wollman and D‘Agostino 1997; Laasch et al. 2003).
• This latter occurs most commonly in
overweight patients or when the left lobe of
the liver lies low in the epigastrium covering
access to the stomach

288. Fluoroscopic Gastrostomy
• Inserted directly through the skin into the
stomach
OR
• advanced through the mouth, oesophagus
and stomach and brought out through the
abdominal wall (as in PEG)

289. Radiologically Inserted Gastrostomy
(RIG)
• Also termed percutaneous radiologic gastrostomy
(PRG), allows a tube to be placed directly
percutaneously into the stomach (Preshaw 1981; Wills
and Oglesby 1983).
• Advantages:
– reduced infection rate as the tube is not contaminated by
oral flora,
– avoiding the risk of stoma metastasis from upper GI tumour
seeding and
– provides the option to perform this under local anaesthesia
in high-risk patients (e.g. motor neurone disease).

291. a,b. Müller-Brown gastropexy T-fasteners
A metal bar (arrow) is attached to a suture with a cotton wool bud and aluminium
tubes for crimping (arrowheads) on the outside of the patient. The bar is inserted into
a slot in the delivery needle. c After local anaesthesia the stomach is punctured with
the slotted needle containing the T-fastener. Intragastric position is confirmed and the
T-fastener dislodged from the needle with a pusher (arrow).

293. Per-oral Image-Guided Gastrostomy
(PIG)
• a hybrid of PEG and RIG
• outcomes superior to both methods (Laasch et
al.2003)
• It can be used as a routine alternative to PEG.
• also appropriate for use where endoscopic
gastrostomy has failed but RIG is not necessarily
indicated.
• The procedure is simple and does NOT require
the use of gastropexy sutures or the use of an
endoscope.

294. a Over-the-wire push gastrostomy tubes:
A, assembled 20-Fr Corflo gastrostomy (Merck). B, 14- Fr MicKey gastrostomy (Vygon). The tube
itself is joined (arrow) to a long tapered dilator shaft (arrowheads).
b The stomach is inflated through a naso-gastric tube (arrow).

295. c The puncture needle (arrow) is inserted in a straight line below the cardia.
d Over a wire the needle is exchanged for a valved vascular sheath (arrow).

296. e A Headhunter 1 catheter (arrow) is advanced onto the cardia. In this case cannulation is made
easy by the presence of an axial hiatus hernia (arrowheads).
f Catheter and wire (arrow) are manipulated up the oesophagus following the line of the
nasogastric tube (arrowhead).
g Push-gastrostomy in situ