Azygos Vein - Lecture Note

AZYGOS VEIN1INTRODUCTIONSITUATION/POSITION:- Azygos vein is present(1) Only on the Right side of body2 Upper part of posterior abdominal wall.(3) In Posterior Mediastinum.DIPANNA RAR.It is provided with valves and may appear tortuous.It connects the Inferior Vena Cava with the Superior Vena Cava.Ir also connects portal venous system, vertebral venous system.FUNCTIONS :- The functions of azygus vein are as follows1Drains lumber venous region. blood from the thwacic wall and upper2Forms Superior an vena important cara collateral and Inferior channel vena connecting cava. theCOURSE AND TERMINATIONThe abdomen Azygos rein after formation ascends up and leave thediaphragm by passing through the aortic opening of theEntersinthe posterior medicstinum.DIPANRAR RAYHere it the ascends level vertically lying in front of vertebral columnupto of T4 vertebrae.Here, to Then terminate arches in forwards the above the hilum of lung (Right)the 2nd Superior venacava at the level ofcostal Cartilage. AZYGOS VEIN2FORMATIONThe Azygos vein is formed by union of the(is veins. Lumber azygos (ii) Right Subcostal and (iii) Right Ascending lumberDIPARKARIMY1The lumber azygos vein may be regarded as the abdominalpart of the azygus vein. It lies to the right of the lumbarVena Cava.vertebrae. ITS lower end communicates with the Inferior2The Right Subcostal vein accompanies the corresponding artery.3The Ascending lumber vein is famed by vertical anastomosesformed that connect union the lumber veins The azygos vein belumber veins. by of the right subcostal and ascending may AZYGOS VEIN3RELATIONSANTERIORIX- Oesophagus (Right edge)POSTERIORLY :-(1)Lower 8th Thoracic vertebra.2Right posterior intercostal arteriesTO THE RIGHT:-(1)Right lung and Pleura.2Greater splanchnic nerves.VENNDIPANKAR RAYTO THE LEFT:- (A) LOWER PART if Thoracic duct (ii) Aorta.(B) UPPER PART - (i) Oerphagus (ii) TracheaARCH OF AZYGOS VEIN:- It is. related -(iii) Vegus nerveBELOW:- To the root of Right lung.RIGHT SIDE: - To the Right lung an pleura.LERT SIDE:- Right border of Oesophagus , Trachea, Right Vagus Nerve.TRIBUTARIES(1) 5th to 11th right posterior intercostal veins except first(22nd, 3rd and 4th posterior intercostal veins.Right Superior intercostal vein formed by union of the3Hemiazygos vein - At the level of T7 or T8 Vertebrae.(4 Accessory hemiazygos vein- - At the level of T8 orTg vertebrae.(5) Right bronchial vein- Near - terminal end of the azygos vein.(6) Right Subcostal vein DIPANKAR RAY(7) Right ascending lumber vein8Oesophageal veins with the exception of those at its lower end.(9) Mediastinal veins.(10) Pericardial veins