Stomach Fx Normal Dx Anatomy Multimodality Applied Anatomy

<
<

Stomach


cropped-Stomach-header-01.jpg

2. Definition


Page 2 – Definition


Definition
– The stomach is a muscular, hollow organ in the gastrointestinal system that lies between the esophagus and duodenum.
  • It serves as a reservoir and mixer for ingested food, initiating mechanical and chemical digestion, particularly of proteins.

  • Structurally, it consists of four regions (cardia, fundus, body, and pylorus), and is lined by glandular mucosa that secretes acid, enzymes, and mucus.

  • It also functions as a controlled gatekeeper, regulating emptying into the duodenum via the pyloric sphincter.

  • Diseases include gastritis, ulcers, gastric cancer, and gastroparesis.

  • Diagnosed via endoscopy, imaging (e.g., CT, upper GI series), and biopsy, and treated medically or surgically depending on etiology. |


Core Element Summary
Structure Muscular, J-shaped organ with rugae; four regions; surrounded by omentum
Function Receives ingested material → mechanically and chemically digests → exports chyme to duodenum
Common Diseases Gastritis, peptic ulcer disease, gastric cancer, gastroparesis
Diagnosis Endoscopy, barium swallow, CT, biopsy
Treatment PPIs, antibiotics (for H. pylori), surgery (e.g., resection, gastrectomy)

3. Anatomy


Page 3 – Normal


🔹 Table 1 – U-SSPCT–C (Structural Anatomy)

Component Detail
Units (U) Cardia, fundus, body (corpus), antrum, pylorus
Size (S) 25–30 cm long; holds ~1.5–2.5 liters postprandially
Shape (S) J-shaped organ with greater and lesser curvatures
Position (P) Left upper quadrant; intraperitoneal; between esophagus (above) and duodenum (below)
Character (C) Mucosa: glandular epithelium with gastric pits and glands; muscularis externa with 3 layers (longitudinal, circular, oblique); rugae allow distention
Time (T) Formed from embryologic foregut; active digestion starts shortly after birth
Connections – Arterial Supply Left gastric, right gastric, left gastroepiploic, right gastroepiploic, and short gastric arteries (from celiac trunk)
Connections – Venous Drainage Left and right gastric veins → portal vein; gastroepiploic and short gastric veins → splenic vein
Connections – Lymphatic Drainage Gastric, gastroepiploic, and celiac lymph nodes
Connections – Nerve Supply Parasympathetic: vagus nerve; sympathetic: celiac plexus
Connections – Ducts None (not a gland with excretory duct)

🔹 Table 2 – Function (Receive → Process → Export)

Stage Description
Receive Receives food from the esophagus via the lower esophageal sphincter
Process Mechanically churns and mixes food with gastric secretions (HCl, pepsin, intrinsic factor); converts food into chyme
Export Gradually releases chyme into the duodenum through the pyloric sphincter under neural and hormonal control

4. Disease and Diagnosis


Table 1 – Disease Categories and Structural Effects (U-SSPCT–C)

Disease Category Examples Anatomic Change Affected U-SSPCT–C Element
Inflammatory Gastritis (H. pylori, autoimmune) Mucosal erythema, edema Character
Glandular atrophy Character
Infectious H. pylori, CMV gastritis Mucosal erosion Character
Nodularity or lymphoid aggregates Character, Units
Neoplastic – Benign Hyperplastic polyps, adenomas Discrete mucosal growths Unit
Smooth, rounded shape Shape
Neoplastic – Malignant Adenocarcinoma, lymphoma Mass lesion, ulceration Unit
Wall thickening, invasion Character, Shape
Regional lymph node involvement Connections – Lymphatics
Mechanical Gastric outlet obstruction Pyloric narrowing Position
Dilated stomach, delayed emptying Size, Time
Trauma Perforated ulcer Wall defect, free air Unit, Character
Peritoneal contamination Connections
Metabolic Zollinger-Ellison syndrome Mucosal hypertrophy, increased folds Character, Shape
Circulatory Ischemic gastritis Pale or hemorrhagic mucosa Character
Portal hypertensive gastropathy Congested rugal folds
Inherited Juvenile polyposis Multiple polyps Unit
Risk of malignant transformation Time
Infiltrative Linitis plastica (diffuse adenocarcinoma) Rigid wall, thickened stomach Character, Shape
Loss of peristaltic compliance Function
Idiopathic Gastroparesis Delayed gastric emptying Time, Function
Iatrogenic Post-bypass strictures Altered anatomy, surgical anastomosis Unit, Connections
Functional Functional dyspepsia Normal structure, abnormal sensation Character
Psychiatric Anorexia, bulimia Delayed emptying, muscle atrophy Time, Character

5. History and Culture


Page 5 – History, Culture, and Art


🔹 1. History of Anatomy

Contributor / Era Milestone
Ancient Egypt and Greece Recognized abdominal cavity contents but unclear organ boundaries
Galen Described the stomach as a vessel of digestion and emotion
Ibn Sina (Avicenna) Wrote about gastric pain and disorders in The Canon of Medicine
Andreas Vesalius (1543) Illustrated stomach anatomy with curvature and sphincters
18th–19th century Identification of gastric regions and lining layers

🔹 2. History of Physiology

Era Discovery
1820s – William Beaumont Observed digestion in a patient with gastric fistula (Alexis St. Martin)
19th century Hydrochloric acid identified as key digestive agent
Early 20th century Pepsin and gastric hormones (gastrin) isolated
Modern era Understanding of acid regulation, neurohormonal control, and motility refined

🔹 3. History of Disease

Era Milestone
Antiquity Gastric discomfort interpreted as imbalance of “humors”
19th century Peptic ulcer identified; early surgeries performed
1982 – Warren and Marshall Discovered Helicobacter pylori as cause of most ulcers
Modern era Link between H. pylori and gastric cancer established; widespread eradication programs launched

🔹 4. History of Diagnosis

Tool Milestone
Early auscultation Used to assess borborygmi and gas movement
Barium swallow Introduced in early 1900s
Endoscopy (EGD) Became routine in mid-20th century
Histopathology Allowed precise diagnosis of malignancy and gastritis subtypes

🔹 5. History of Imaging

Modality Use
Barium studies Detected ulcers, strictures, masses
Endoscopy Visualized mucosa, ulcers, varices, cancer
CT / MRI Staging gastric malignancies, detecting perforation
PET-CT Advanced oncology staging in modern practice

🔹 6. History of Laboratory Testing

Test Milestone Use
Gastric pH testing 20th century Evaluated acid output
H. pylori testing 1980s Revolutionized ulcer diagnosis
Gastrin levels Used to diagnose Z-E syndrome
Tumor markers CA 19-9, CEA Adjuncts in cancer monitoring

🔹 7. History of Therapies

Therapy Era Details
Dietary change Ancient remedy “Soft foods” prescribed for stomach pain
Antacids 20th century Symptom relief without addressing cause
Antibiotics + PPIs 1990s onward Eradicated H. pylori and healed ulcers
Gastrectomy 20th century Surgical removal of cancer or refractory ulceration
Endoscopic therapy Modern Ablation, dilation, or stent placement

🔹 8. Cultural Meaning

Culture Symbolism
Traditional medicine Seen as the center of nourishment and health
Chinese medicine Stomach = part of Earth element, center of digestion
Popular idioms “Gut feeling,” “stomach turning,” “stomaching the truth”

🔹 9. Artistic Representations

Medium Example Meaning
Medieval drawings Alimentary tract schematics Emphasized hierarchy of digestion
Anatomical models Teaching tools in 17th–20th century Showed food passage and gastric chambers
Surrealist imagery Twisted or distorted stomach forms Represent anxiety and inner turmoil

🔹 10. Literary References

Author / Work Context Theme
Shakespeare – “I can scarce digest this…” Emotional rejection
Dante’s Inferno Gluttony punished in the third circle Stomach as metaphor for excess
Kafka’s Hunger Artist Voluntary starvation The stomach as identity and rebellion
Folklore and fairy tales “Swallowed whole” motifs Hunger, consumption, and fear

🔹 11. Music and Performing Arts

Context Link to Stomach Notes
Opera/vocal projection Requires diaphragmatic support and gastric relaxation Tension in abdominal cavity affects performance
Choreography and dance Center of gravity often described as the “core” Visualized near the stomach
Satire and lyrics “Stomach this” used metaphorically Reflects difficulty with emotional digestion

🔹 12. Athletics and Performance

Context Role of Stomach Examples
Endurance sports Gastric emptying affects performance Delayed emptying = cramping, nausea
Pre-event nerves Sympathetic stimulation reduces gastric motility “Butterflies in the stomach”
Nutrition in training Carb-loading and meal timing critical Risk of GERD or bloating with poor timing

🔹 13. Culinary and Nutritional Use

Use Region Details
Tripe (stomach lining) Global – Italy, Mexico, Asia Popular traditional dish (e.g., menudo, pho, andouille)
Stomach-stuffed meats Scotland (haggis), Middle East Organ serves as cooking vessel
Symbol of fullness “Stuffed to the stomach” Universal concept of satiety

🔹 14. Notable Individuals with Stomach Disease

Name Condition Note
Napoleon Bonaparte Believed to have died of gastric cancer
Ulysses S. Grant Died from gastric cancer
Carl Jung Experienced lifelong digestive issues
Randy Pausch Carnegie Mellon professor, died of stomach cancer; gave famous “Last Lecture”

🔹 15. Famous Quotes and Sayings

Quote Meaning
“No guts, no glory.” Courage metaphor through abdomen
“Butterflies in the stomach.” Performance anxiety
“Hard to stomach.” Emotionally difficult to accept
“A gut feeling.” Instinctive knowledge
“Stomach turning.” Disgust or revulsion

8. Memory Image


MCQ 1 – Basic Science

Which of the following cell types in the stomach secretes hydrochloric acid?

A. Chief cells
B. G cells
C. Parietal cells
D. Mucous neck cells


Correct Answer Table

Correct Answer Explanation
C. Parietal cells Parietal cells in the gastric glands secrete hydrochloric acid and intrinsic factor.

Incorrect Answer Table

Option Reason It Is Incorrect
A. Chief cells Secrete pepsinogen, not acid
B. G cells Secrete gastrin, not acid
D. Mucous neck cells Secrete mucus, not acid

🔹 MCQ 2 – Basic Science

Which region of the stomach is primarily responsible for mixing and grinding food into chyme?

A. Cardia
B. Fundus
C. Body
D. Antrum


Correct Answer Table

Correct Answer Explanation
D. Antrum The antrum is the distal stomach region responsible for strong contractions that grind food before it enters the duodenum.

Incorrect Answer Table

Option Reason It Is Incorrect
A. Cardia Entry point, not involved in grinding
B. Fundus Stores gas and food, not grinding
C. Body Secretes acid and enzymes but does not perform major grinding

🔹 MCQ 3 – Clinical

A 45-year-old patient with chronic epigastric pain and recent melena is found to have a duodenal ulcer. Which organism is most likely responsible?

A. E. coli
B. H. pylori
C. CMV
D. Candida


Correct Answer Table

Correct Answer Explanation
B. H. pylori Helicobacter pylori is the most common cause of duodenal and gastric ulcers.

Incorrect Answer Table

Option Reason It Is Incorrect
A. E. coli Causes diarrhea and UTIs, not ulcers
C. CMV Causes ulcers only in immunocompromised
D. Candida Can infect the stomach but not typically associated with ulcers

🔹 MCQ 4 – Clinical

Which of the following is most suggestive of gastric carcinoma?

A. Intermittent heartburn relieved by antacids
B. Sharp postprandial pain in upper abdomen
C. Unintended weight loss and early satiety
D. Hemorrhoids and bright red rectal bleeding


Correct Answer Table

Correct Answer Explanation
C. Unintended weight loss and early satiety These are common signs of a gastric mass restricting gastric capacity or motility.

Incorrect Answer Table

Option Reason It Is Incorrect
A. Heartburn More indicative of GERD
B. Postprandial pain Suggestive of ulcer
D. Rectal bleeding Localized to lower GI tract, not stomach

🔹 MCQ 5 – Radiologic

On upper GI series, which finding is characteristic of a gastric ulcer?

A. Apple core lesion
B. Filling defect with smooth borders
C. Ulcer crater with radiating folds
D. Beak sign at pylorus


Correct Answer Table

Correct Answer Explanation
C. Ulcer crater with radiating folds Classic radiologic sign of a benign gastric ulcer.

Incorrect Answer Table

Option Reason It Is Incorrect
A. Apple core lesion Indicates colon cancer
B. Smooth filling defect Often a polyp
D. Beak sign Associated with achalasia, not ulcers

🔹 MCQ 6 – Radiologic

What is the most appropriate first-line imaging test for suspected gastric outlet obstruction?

A. Chest X-ray
B. Abdominal ultrasound
C. Upper GI barium series
D. MRI abdomen


Correct Answer Table

Correct Answer Explanation
C. Upper GI barium series Best non-invasive method to evaluate passage through the stomach and duodenum.

Incorrect Answer Table

Option Reason It Is Incorrect
A. Chest X-ray May show air-fluid levels but not diagnostic
B. Ultrasound Limited for gas-filled stomach
D. MRI abdomen Too expensive and not first-line

🔹 MCQ 7 – Radiologic

Which of the following is best for staging gastric cancer?

A. CT scan
B. Endoscopy
C. PET-CT
D. Abdominal X-ray


Correct Answer Table

Correct Answer Explanation
C. PET-CT Used for detecting metastatic spread in staging gastric carcinoma.

Incorrect Answer Table

Option Reason It Is Incorrect
A. CT scan Good for local assessment but less sensitive than PET for distant disease
B. Endoscopy Used for diagnosis, not staging
D. Abdominal X-ray No role in cancer staging
>
>