HISTOLOGY OF ESOPHAGUS & GASTRO ESOPHAGEAL JUNCTION By Dr. Sobia Ibrahim Assistant Professor Anatomy, KEMU.

HISTOLOGY OF ESOPHAGUS &GASTRO ESOPHAGEAL JUNCTION

By Dr. Sobia Ibrahim

Assistant Professor Anatomy,

KEMU

ESOPHAGUS

Is muscular tube

Extends from pharynx

to stomach

Wall has four layers:

Mucosa

Epithelium

Lamina propria

Muscularis interna or

muscularis mucosae

Submucosa

Muscularis externa

Adventitia / Serosa

UPPER 1/3 OF ESOPHAGUS MUCOSA

Epithelium: Stratified squamous non-keratinized

Lamina propria: scattered lymphocytes, few lymphatic nodules, mucous glands, blood vessels

Muscularis mucosae: Thick, smooth muscles

longitudinally arranged

SUB-MUCOSA Collagen & elastic fibres,

mucous glands, blood vessels, nerves

MUSCULARIS EXTERNA Skeletal (striated) muscles

ADVENTITIA Collagen & elastic fibers,

blood vessels

MIDDLE 1/3 OF ESOPHAGUS MUCOSA Epithelium: stratified squamos non-

keratinized Lamina propria: : scattered lymphocytes,

few lymphatic nodules, mucous glands, blood vessels

Muscularis mucosae: thick, smooth muscles longitudinally

arranged

SUB-MUCOSA Collagen & elastic fibres, mucous glands,

blood vessels, nerves

MUSCULARIS EXTERNA Skeletal (striated) muscles, Smooth muscles

ADVENTITIA Collagen & elastic fibers, blood &

lymphatic vessels

LOWER 1/3 OF ESOPHAGUS

MUCOSA Epithelium: Simple columnar

Lamina propria: scattered lymphocytes, few lymphatic nodules, mucous glands, blood vessels

Muscularis mucosae: thick, smooth muscles

longitudinally arranged

SUB-MUCOSA Collagen & elastic fibres, mucous

glands, blood vessels, nerves

MUSCULARIS EXTERNA Smooth muscles

ADVENTITIA/ SEROSA Collagen & elastic fibers, blood &

lymphatic vessels

GASTROESOPHAGEAL REFLUX DISEASE

It is associated with incompetent barriers at this junction; caused by hiatal hernia, decrease in lower esophageal sphincter tone.

Results in reflux esophagitis as mucosal barriers are not sufficient to protect esophagus from acids, pepsin & bile

causing heart burns/atypical chest pain

BARRETT’S ESOPHAGUS

Reflux of gastric contents throu lower esophageal sphincter Gastric acid in esophagus Heart burn With time, metaplasia of epithelium (protective) Barrett’s esophagus High risk for carcinoma

STOMACH

PARTS OF STOMACH

Cardia

Fundus

Body

Pylorus

Rugae

Three histological zones

CARDIOESOPHAGEAL JUNCTION

Esophageal cardiac junction

MUCOSA:1:Epithelium changes from: Startified squamous non keratinised into simple columnar.2: Lamina propria: esophageal cardiac glands but in stomach (cardiac, fundic and pyloric glands).They are tubular and deep.3:Muscularis mucosae: thick longitudinal in esophagus but thin and two layered in stomach.Submucosa: esophageal glands proper disappear. No glands in submucosa of stomach.Muscularis externa: three layered in stomach an additional oblique layer is there

GASTROESOPHAGEAL REFLUX DISEASE

• It is associated with incompetent barriers at this junction; caused by hiatal hernia, decrease in lower esophageal sphincter tone.

• Results in reflux esophagitis as mucosal barriers are not sufficient to protect esophagus from acids, pepsin & bile

• causing heart burns/atypical chest pain