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STOMACH
ANATOMY
PARTS OF STOMACH
BLOOD SUPPLY OF THE STOMACH
• Left gastric artery, a branch of coeliac artery
• Right gastric artery, a branch of hepatic
artery.
• Right gastroepiploic artery, a branch of gastro
duodenal artery.
• Left gastroepiploic artery, a branch of splenic
artery.
• Short gastric arteries, branches of splenic
artery.
BLOOD SUPPLY OF STOMACH
VENOUS DRAINAGE OF STOMACH
Right and left gastric veins drain into portal vein.
Right gastroepiploic vein drains into superior
mesenteric vein.
Left gastroepiploic vein and short gastric veins
drain into splenic vein.
Prepyloric vein of Mayo distinguishes pyloric
canal from the first part of duodenum.
NERVE SUPPLY
• Intrinsic innervation occurs through myenteric
plexus of Auerbach and submucous plexus of
Meissner.
• Right vagus is posterior and left vagus is
anterior.
• Posterior vagus gives criminal nerves of Grassi,
which supply lower oesophagus and fundus of
stomach, which, if not cut properly during
vagotomy, may lead to recurrent ulcer
NERVE SUPPLY
• Gastroduodenal pain is sensed via
sympathetic fibres (T5-T10).
HISTOLOGY
• The fundus and body contains parietal and
chief cells.
• Parietal cells secrete acid and intrinsic factor.
• Chief cells produce pepsinogen.
• In the antrum, endocrine cells produce gastrin
(G cells) and somatostatin (D cells).
LYMPHATIC DRAINAGE
INVESTIGATION OF THE STOMACH AND
DUODENUM
GASTRIC FUNCTION TESTS
• Pentagastrin test/Kay’s augmented histamine
test
• Hollander’s insulin test
• Radioisotope labelled gastric emptying study
• 24 hours intragastric pH monitoring
• Gastrin level estimation
FLEIBLE ENDOSCOPY
• Gold standard
• Use a solid-state camera mounted at the
instrument’s tip
• More sensitive than conventional radiology
• Diagnostic and theraputic
• Complications
ENDOSCOPE
VIEW OF NORMAL STOMACH
CONTRAST RADIOLOGY
• Barium meal / follow-through
• CT with oral contrast
ULTRASONOGRAPHY
• Standard ultrasound imaging - less sensitive
than other modalities
• Endoluminal ultrasound and laparoscopic
ultrasound are probably the most sensitive
techniques available in the preoperative
staging of gastric cancer.
– Depth of invasion
– Enlarged lymph nodes
– Liver metastasis
• An additional use of ultrasound is in the
assessment of gastric emptying.
CT/MRI
• Gastric wall thickening associated with a
carcinoma of any reasonable size can be easily
detected by CT, but the investigation lacks
sensitivity in detecting smaller and curable
lesions
• Lymph node metastasis
• Liver metastasis
• Limitations
POSITRON EMISSION TOMOGRAPHY
(PET)
• Functional imaging technique that relies on
the uptake of a tracer, by metabolically active
tumour tissue
• Fluorodeoxyglucose (FDG) isthe most
commonly used tracer
• Anatomical and functional information need
to be linked - CT/PET
• Preoperative staging of gastro-oesophageal
cancer - often demonstrates occult spread
LAPAROSCOPY
• Assessment of gastric cancer
• Peritoneal assessment and cytology
• Posterior extent may not be accessible
GASTRIC EMPTYING STUDIES
• Useful for studying gastric dysmotility problems,
particularly those that follow gastric surgery
• A radioisotope-labelled liquid and solid meal is
ingested and the emptying of the stomach is
followed on a gamma camera
• The proportion of activity in the remaining
stomach to be assessed numerically, and it is
possible to follow liquid and solid gastric
emptying independently
ANGIOGRAPHY
• Angiography is used most commonly in the
investigation of upper gastrointestinal
bleeding that is not identified using
endoscopy.
• Therapeutic embolisation may also be of
value in the treatment of bleeding in patients
in whom surgery is difficult or inadvisable