Notes on the Esophagus(Dec _15)

NOTES ON THE ESOPHAGUS

ESOPHAGUS:-10 inches (25cms) long

-Extends from the level of the lower border of the cricoid cartilage to the cardiac orifice of the stomach

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PORTIONS OF THE ESOPHAGUS:

I. CERVICAL:IN THE NECK:

-COMMENCES IN THE MEDIAN PLANE -APPROACHES THE THORACIC INLET-DEVIATES SLIGHTLY TO THE LEFT

ANTERIOR RELATIONS:

THE TRACHEA AND THE THYROID GLAND

POSTERIOR RELATIONS:

THE LOWER CERVICAL VERTEBRAE AND PREVERTEBRAL FASCIA

ON EITHER SIDE :

COMMON CAROTID ARTERIES AND THE RECURRENT LARYNGEAL NERVES

ON THE LEFT SIDE:

-SUBCLAVIAN ARTERY AND THE TERMINAL PART OF THE THORACIC DUCT

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2. THORACIC:

-Traverses first the superior and then the posterior mediastinum

COURSE:

FROM BEING SOMEWHAT OVER TO THE LEFT OF MIDLINE AT T5 THEN PASSES DOWNWARDS, FORWARDS AND TO THE LEFT--> REACH THE ESOPHAGEAL OPENING IN THE DIAPHRAGM (T10)RELATIONS

ANTERIOR:

-TRACHEA-THE LEFT BRONCHUS (WHICH CONSTRICTS IT)-THE PERICARDIUM (SEPARATING IT FROM THE LEFT ATRIUM) DIAPHRAGM

-PAGE 3-POSTERIOR:

-THORACIC VERTEBRAE-THORACIC DUCT, THE AZYGOS VEIN AND ITS TRIBUTARIES- THE DESCENDING AORTA

ON THE LEFT SIDE:-LEFT SUBCLAVIAN ARTERY-THE TERMI- NAL PART OF THE AORTIC ARCH-THE LEFT RECURRENT LARYNGEAL NERVE-THE THORACIC DUCT AND THE LEFT PLEURA-IN THE POSTERIOR MEDIASTINUM:

THE DESCENDING THORACIC AORTA BEFORE THIS PASSES POSTERIORLY TO THE ESOPHAGUS ABOVE THE DIAPHRAGM RIGHT SIDE: PLEURA AND THE AZYGOS VEIN.IN THE ABDOMEN:

-PASSING FORWARDS THROUGH THE OPENING IN THE RIGHT CRUS OF THE DIAPHRAGM-ESOPHAGEAL GROOVE ON THE POSTERIOR SURFACE OF THE LEFT LOBE OF THE LIVER,(COVERED BY PERITONEUM ON ITS ANTERIOR AND LEFT ASPECTSBEHIND:

LEFT CRUS OF THE DIAPHRAGMSTRUCTURE:

1. AN OUTER CONNECTIVE TISSUE SHEATH OF AREOLAR TISSUE2. A MUSCULAR LAYER OF EXTERNAL LONGITUDINAL AND INTERNAL CIRCULAR FIBRES WHICH ARE STRIATED IN THE UPPER TWO-THIRDS AND SMOOTH IN THE LOWER ONE-THIRD3. A SUBMUCOUS LAYER CONTAINING MUCOUS GLANDS4. A MUCOSA OF STRATIFIED EPITHELIUM PASSING ABRUPTLY INTO THE COLUMNAR EPITHELIUM OF THE STOMACH.

BLOOD SUPPLY:ARTERIES:

-FROM THE INFERIOR THYROID ARTERY-BRANCHES OF THE DESCENDING THORACIC AORTA-LEFT GASTRIC ARTERYVEINS:

THE CERVICAL PART-- INFERIOR THYROID VEINS FROM THE THORACIC PORTIONà AZYGOS VEIN FROM THE ABDOMINAL PORTION PARTLY INTO THE AZYGOS AND PARTLY INTO THE LEFT GASTRIC VEINS.

-PAGE 4-LYMPH DRAINAGE OF ESOPHAGUS:

Lymphatics from the upper third of esophagus drainàDEEP CERVICAL NODESLymphatics from the middle third àSUPERIOR AND POSTERIOR MEDIASTINAL NODES Lymphatics from the lower third àCELIAC NODES ADDITIONAL LYMPHATIC DRAINAGE:

PERI-ESOPHAGEAL LYMPH PLEXUS FR POSTERIOR MEDIASTINAL NODESSUPRACLAVICULAR NODES AND INTO NODES AROUND THE LEFT GASTRIC VESSELSUNCOMMON TO BE ABLE TO PALPATE HARD, FIXED SUPRACLAVICULAR NODES IN PATIENTS WITH ADVANCED OESOPHAGEAL CANCER.NERVE SUPPLY TO ESOPHAGUS:

-Receives nerve fibers from both sympathetic and parasympathetic nervous systems-Parasympathetic fibers are supplied via the right and left vagus nerves-The sympathetic fibers (both efferent and afferent) are supplied through the sympathetic trunks.RADIOGRAPHICALLY:

THE ESOPHAGUS IS STUDIED BY X-RAYS TAKEN AFTER A BARIUM SWALLOWàLYING IN THE RETROCARDIAC SPACE JUST IN FRONT OF THE VERTEBRAL COLUMN ANTERIORLY, THE NORMAL ESOPHA GUS IS INDENTED FROM ABOVE DOWNWARDS :THREE MOST IMPORTANT STRUCTURES THAT CROSS IT THE 1. ARCH OF THE AORTA, 2. THE LEFT BRONCHUS AND 3. THE LEFT ATRIUMCLINICAL FEATURES:

1. FOR ESOPHAGOSCOPY:

-MEASUREMENTS ARE MADE FROM THE UPPER INCISOR TEETH; THE THREE IMPORTANT LEVELS:|

a. IN 17 CMàCORRESPOND TO THE COMMENCEMENT OF THE ESOPHAGUSb. IN 28 CM)POINTàCROSSED BY THE LEFT BRONCHUS c. IN (43 CM)àTERMINATION OF ESOPHAGUS 2. THREE POINTS:

a. INDICATE THE NARROWEST PARTS OF THE OESOPHAGUSb. THE SITES AT WHICH, AS MIGHT BE EXPECTED, SWALLOWED FOREIGN BODIES ARE MOST LIKELY TO BECOME IMPACTEDc. STRICTURES TO OCCUR AFTER SWALLOWING CORROSIVE FLUIDS3. THE ANASTOMOSIS BETWEEN THE AZYGOS (SYSTEMIC) AND LEFT GASTRIC (PORTAL) VENOUS TRIBUTARIES IN THE ESOPHAGEAL VEINS IS OF GREAT IMPORTANCEàIN PORTAL HYPERTENSION THESE VEINS DISTENDLARGE COLLATERAL CHANNELSà ESOPHAGEAL VENOUS PLEXUS

-PAGE 5-4. CLOSE RELATIONSHIP BETWEEN THE OESOPHAGUS AND THE LEFT ATRIUMàTHE DEGREE OF LEFT ATRIAL ENLARGEMENT IN MITRAL STENOSIS-BARIUM SWALLOW MAY SHOW MARKED BACKWARD DISPLACEMENT OF THE ESOPHAGUS CAUSED BY THE DILATED ATRIUM5. ESOPHAGUS IS CROSSED ONLY BY THE VENA AZYGOS ON THE RIGHT SIDEàTHE SIDE OF ELECTION TO APPROACH THE ESOPHAGUS SURGICALLY.SENSORY AND PARASYMPATHETIC MOTOR FIBRES TO THE ESOPHAGUSàTHE VAGI AND THEIR RECURRENT LARYNGEAL BRANCHES.SENSORY AND PARASYMPATHETIC MOTOR FIBRES TO THE ESOPHAGUSàTHE VAGI AND THEIR RECURRENT LARYNGEAL BRANCHESSENSORY AND PARASYMPATHETIC MOTOR FIBRES TO THE ESOPHAGUSàTHE VAGI AND THEIR RECURRENT

LARYNGEAL BRANCHES.

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