Type of Article:  Original Research

Volume 5; Issue 3.2 (August 2017)

Page No.: 4299-4302

DOI: https://dx.doi.org/10.16965/ijar.2017.317


M  Shilpa *1, K R Dakshayani 2.

*1 Postgraduate, Department of Anatomy, Mysore Medical College & Research Institute, Mysore. Karnataka, India.

2 Professor & Head, Department of Anatomy, Mysore Medical College & Research Institute, Mysore. Karnataka, India

Address for Correspondence:  Dr. M  Shilpa, Postgraduate, Department of Anatomy, Mysore Medical College & Research Institute, Mysore. Karnataka, India. Mobile No: 7411543525 E-Mail: shilpa_ramling@yahoo.co.in


Background: The azygos venous system consists of the azygos vein on the right side and the hemiazygos and accessory hemiazygos on the left side. The latter two are said to be the tributaries rather than the equivalent of the azygos vein. This unpaired venous system is said to be full of anatomical variations and hence of much clinical significance.

Aim: To study and report the prevalence of any anatomical variation of azygos venous system.

Materials and Methods: The present study was carried out in the Department of Anatomy, MMC & RI, Mysore, over a period of 2 years. A total of 20 cadavers irrespective of age and sex were dissected for study purpose. The entire course of the azygos venous system in these 20 cadavers was carefully dissected and documented.

Observations:  In present study among 20 cadavers, 2 adult male cadavers showed variation during dissection of posterior thoracic wall, we found that in one cadaver azygos vein running on left side of vertebral column, hemiazygos and accessory hemiazygos veins were absent.  In another cadaver we found that arch of azygos on left side with osteophytic changes of vertebral column.

Conclusion: Venous abnormalities often complicate mediastinal surgery with intra operative hemorrhage. Prior knowledge of possible anatomical variations may help the surgeons to reduce the risk of such events. Also presence of such variations may lead to misinterpretation of thoracic CT and MRI findings of the posterior mediastinum.

KEY WORDS: Azygos vein, Hemiazygos vein, Accessory hemiazygos vein.


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Cite this article: M Shilpa, K R Dakshayani. A CADAVERIC STUDY OF AZYGOS VENOUS SYSTEM. Int J Anat Res 2017;5(3.2):4299-4302. DOI: 10.16965/ijar.2017.317