类别 全部 - anatomy - muscle

作者:hetal vithalani 11 年以前

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Esophagus Pathology by Hetal Vithalani

The esophagus is a muscular tube that begins at the cricoid cartilage and ends at the gastroesophageal junction. It descends along the anterior surface of the thoracic vertebrae and passes posterior to the left atrium.

Esophagus Pathology by Hetal Vithalani

Esophagus Pathology by Hetal Vithalani

Begins at cricoid cartilage (vertebral level C6), ends at GE (gastroesophageal) junction.

The esophagus descends on the anterior surface of the thoracic vertebrae to the right of the thoracic aorta.

The esophagus passes posterior to the left atrium.

Clinical Correlate: Enlargement of the left atrium (as a result of mitral stenosis, for example) → impingement on the esophagus and symptoms of dysphagia. It can also be visualized by barium swallow or EGD.

The esophagus exits the thoracic cavity and enters the abdominal cavity via the esophageal hiatus of the diaphragm, located at T10.

The esophagus is surrounded by muscle that is responsible for peristalsis.

less

- Skeletal muscle in upper 5% of esophagus

- Skeletal and smooth in the middle 45%

- Smooth in the distal 50%

Esophagitis

Barrett Esophagus

Barrett Esophagus

Metaplasia of the lower esophageal mucosa from stratified Squamous epithelium to nonciliated columnar epithelium with goblet cells.

1. response of lower esophageal stem cells to acidic stress

May progress to dysplasia and adenocarcinoma

Gastroesophageal Reflux Disease (GERD)

GERD

Reflux of acid from the stomach due to reduce LES tone

Risk factors includes

Alcohol

Tobacco

Obesity

Fat rich diet

caffeine

hital hernia


Clinical features

Heartburn ( mimics cardia chest pain)

Asthma (adult onset) and cough

Damage to enamel of teeth

Ulceration with stricture and Barrett esophagus are late complication

Congental

Esophageal Web

Esophageal Web

Thin protrusion of esophageal mocosa, most often in the upper esophagus.

Present with dysphagia for poorly chewed food

increased risk for esophageal squamous cell carcinoma

plummer - winson sysndromes characterized by severe iron deficiency anemia, esophageal web, and beefy red toungue due to atrophic glossitis.




Middle age women

Schatzki ring are web like narrowings at the gastroesophageal junction.

Tracheoesophagel Fistula

Tracheoesophageal Fistula

abnormal connection (fistula) between trachea and esophagus, commonly congenital

Clinical presentation




Maternal polyhydramnios → excess amniotic can be detected prenatally → amniotic fluid is not recycled as efficiently but is still produced by fetal kidney.


Connection between stomach and trachea: stomach/abdominal distention in newborn (CXR→air bubble in stomach) & ↑ risk of chemical pneumonia (pneumonitis)

Blind ending esophagus: Difficulty feeding (choking and vomiting), can’t pass feeding tube into newborns stomach


Motor Disorder

Hiatus Hernia

A hiatus hernia or hiatal hernia is the protrusion (or herniation) of the upper part of the stomach into the thorax through a tear or weakness in the diaphragm.

Risk factors

Increased pressure within the abdomen caused by:

Heavy lifting or bending over

Frequent or hard coughing

Hard sneezing

Pregnancy and delivery

Violent vomiting

Straining with constipation

Obesity (extra weight pushes down on the abdomen increasing the pressure)

Use of the sitting position for defecation

Heredity

Smoking[citation needed]

Drug use, such as cocaine

Stress * Diaphragm weakness

Roling hiatus hernia

Rolling (or paraesophageal) hiatus hernia, when a part of the stomach herniates through the esophageal hiatus and lies beside the esophagus, without movement of the gastroesophageal junction. It accounts for the remaining 5% of hiatus hernias.

sliding hiatus hernia

The most common (95%) is the sliding hiatus hernia, where the gastroesophageal junction moves above the diaphragm together with some of the stomach.

Achalasia

A-chalasia [a=not, chalao (greek)= to loosen/relax]: failure of LES relaxation + loss of distal esophageal peristalsis.

Failure of complete LES relaxation: damage to inhibitory (NO synthase producing) neurons that enable relaxation

Degeneration of neurons in esophageal wall

(Auerbach’s / myenteric plexus) → loss of smooth muscle contraction/motility → uncoordinated, or lack of, peristalsis

Note: Inflammation of esophageal myenteric plexus is pathognomonic

↑ risk of esophageal squamous cell carcinoma

most common neuromuscular disorder of the esophagus

Sx: progressive dysphagia to solids and liquids, nocturnal regurgitation of undigested food





Worsening dysphagia (difficulty swallowing) to solid AND liquids indicates motility disorders→ achalasia, myasthenia gravis, stroke, CREST syndrome

Note: Dysphagia limited to solids indicates an obstructive lesion (i.e esophageal web/cancer)


Bird’s beak: proximal esophagus is chronically dilated; LES stays closed during swallowing (acute esophageal tapering at the lower esophageal sphincter and narrowing at the gastro-esophageal junction forms the “beak” of the bird)


Primary achalasia: etiology unknown.

Secondary causes of achalasia: Chagas disease, diabetic neuropathy, esophageal CA, infiltrative disorders such as malignancy, amyloidosis, sarcoidosis



Carcinoma

Benign Esophageal Tumors: leiomyoma is the most common

Adenocarcinoma

Adenocarcinoma

adenoCA in lower 1/3




more common than SCC in the United States and affects Caucasians more than African American.


Adenocarcinoma arises in the distal esophagus.


associated wtih Barrett Esophagus and dysplasia


prognosis is poor.

Squamous cell carcinoma

Squamous cell carcinoma

in upper 2/3 of esophagus



SCC

of the esophagus is the most common type of esophageal cancer in the world, but not in the United states.


SCC affects males more then females, and African American more than caucasins the typical age is usally older than 50 years.


Risk Factors

Heavy somoking

Alcohol

Achalasia

Plummer vinston syndrome

tylosis

prior lye ingestion.


Presentation

SCC of the esophagus is often asymptomatic until late in the course. When symptoms do develpo, they may include progressive dysphagia; weight loss and anerexia; bleeding or hoarseness or cough


DS:

Endoscopy with biopsy


Treatment

surgery with the prognosis being poor


Hematemesis / Lacerations

Esophageal varices
Mallory -Weiss syndrome

Mallory -Weiss Syndrome

Longitudinal laceration of mucosa at the gastroesophageal (GE) junction

caoused by

severe vomiting

(usually due to alcoholism or bulmia)


present with painfull hematemesia

risk of boerhaave syndrome - repture of esophagus leading to air in the mediastinum and sbeutaneous emphysema.



Anatomic Disorders

Zenker Diverticulum

Zenker Diverticulum

outopuching of phyryngeal mucosa throgh an acquired defect in the muscular wall (false diverticulum)

Arises above the upper esophageal sphincter at the junction of the esophagus and pharynx

presents with dyphagia, obstruction, an halitosis ( bad breath)

Atresia