Anatomy and Cell Biology

Korean Association of Anatomists (대한해부학회)
권호 표지
DOI QR코드

DOI QR Code

Variations of azygos vein: a cadaveric study with clinical relevance

  • Received : 2023.03.18
  • Accepted : 2023.07.24
  • Published : 2023.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

The azygos vein can be formed as a single root, two roots, and three roots, namely lateral, intermediate and the medial roots respectively. The hemiazygos vein and the accessory hemiazygos vein are the tributaries of azygos vein rather than its left side equivalents. Its variations, especially in young persons without any relevant risk factors, may result in thromboembolic illness. This study aimed to describe the morphological and morphometric variations of azygos system of veins. The present study was conducted on thirty formalin fixed adult human cadavers by dissecting azygos vein from formation to termination and variations were noted. The azygos vein was formed by a single root in 56.7%, by two roots: the lateral root and intermediate root in 36.7% cases and by the lateral root and medial root in 6.6%. The vertebral level of termination of azygos vein was seen at the level of T4 vertebrae in 70% cases, at the level of T3 vertebrae in 20% of cases and at the level of T5 vertebrae in 10% cases. The course of azygos vein was varying in 13.3%. These morphological variations can be useful while performing mediastinal surgery, mediastinoscopy, surgery of the deformations of the vertebral column, neurovascular surgeries of the retroperitoneal organs, disc herniation and fracture of thoracic vertebrae.

Keywords

Acknowledgement

We are grateful to all the residents and faculty members of Christian medical college, Ludhiana and Rajendra Institute of medical sciences, Ranchi for their help and co-operation during the preparation of this manuscript.

References

  1. Standring S. Mediastinum. In: Standring S, editor. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 40th ed. Churchill Livingstone; 2008. p.939-57. 
  2. Snell RS. Clinical Anatomy. Lippincott Williams & Wilkins; 2004. p. 132. 
  3. Drake RL, Vogl W, Mitchell AWM. Gray's Anatomy for Students. 3rd ed. Elsevier; 2015. p. 197. 
  4. Celik HH, Sargon MF, Aldur MM, Cumhur M. An anomalous course of the interazygos vein. Surg Radiol Anat 1996;18:61-2.  https://doi.org/10.1007/BF03207766
  5. Mezzogiorno A, Passiatore C. An atypic pattern of the azygos venous system in man. Anat Anz 1988;165:277-81. 
  6. Casoni GL, Tomassetti S, Cavazza A, Colby TV, Dubini A, Ryu JH, Carretta E, Tantalocco P, Piciucchi S, Ravaglia C, Gurioli C, Romagnoli M, Gurioli C, Chilosi M, Poletti V. Transbronchial lung cryobiopsy in the diagnosis of fibrotic interstitial lung diseases. PLoS One 2014;9:e86716. 
  7. Seib GA. The azygos system of veins in American whites and American negroes, including observations on the inferior caval venous system. Am J Phys Anthropol 1934;19:39-163.  https://doi.org/10.1002/ajpa.1330190117
  8. Rosse C, Gaddum-Rosse P. Hollinshead's Textbook of Anatomy. 5th ed. Lippincott-Raven; 1997. p. 507. 
  9. Shivanal U, HT G. Anomalous azygos veins - its embryological basis and clinical significance. Int J Res Med Sci 2015;3:2323-6.  https://doi.org/10.18203/2320-6012.ijrms20150624
  10. Piciucchi S, Barone D, Sanna S, Dubini A, Goodman LR, Oboldi D, Bertocco M, Ciccotosto C, Gavelli G, Carloni A, Poletti V. The azygos vein pathway: an overview from anatomical variations to pathological changes. Insights Imaging 2014;5:619-28.  https://doi.org/10.1007/s13244-014-0351-3
  11. Romanes GJ. The thorax. In: Romanes GJ, editor. Cunningham's Manual of Practical Anatomy, Vol 2: Thorax and Abdomen. 15th ed. Oxford University Press; 1986. p.1-82. 
  12. Paraskevas GK, Koutsouflianiotis KN, Patsikas M, Noussios G. What is the history of the term "azygos vein" in the anatomical terminology? Surg Radiol Anat 2019;41:1155-62.  https://doi.org/10.1007/s00276-019-02238-3
  13. Dubois J. In Hippocratis et Galeni Physiologiae Partem Anatomicam Isagoge. Apud Joannem Hulpeau; 1555. p. 18924. Latin. 
  14. Vesalius A. De Humani Corporis Fabrica Libri Septem. Ex Officina Joannis Oporini; 1543. p 37. Latin. 
  15. Prasad M, K J. Variations in formation and termination of azygos vein in South Indian population. Int J Anat Res 2018;6:5384-9.  https://doi.org/10.16965/ijar.2018.212
  16. Radhika D, Nirmala BV, Latha GK. Tributaries of azygos vein. J Evid Based Med Healthc 2016;3:49-51.  https://doi.org/10.18410/jebmh/2016/11
  17. Nirmala BV, Teresa RS. Study of azygos system and its variations. J Evol Med Dent Sci 2015;4:5652-7.  https://doi.org/10.14260/jemds/2015/827
  18. Latha K, Sugavasi R. Study of the azygos system of veins in human cadaver. Int J Curr Res Rev 2013;5:113-7. 
  19. Alves EC, Porciuncula Junior RW, Monte Bispo RF, de Sousa-Rodrigues CF, da Rocha AC. Formation of the azygos vein. Int J Morphol 2011;29:140-3.  https://doi.org/10.4067/S0717-95022011000100024
  20. Mustafa SIA, Ali TO, Ahmed AA. Anatomical variation of the azygos vein in human cadavers. Int J Innov Sci Res 2016;25:368-72. 
  21. Krakowiak-Sarnowska E, Wisniewski M, Szpinda M, Krakowiak H. Variability of the azygos vein system in human foetuses. Folia Morphol (Warsz) 2003;62:427-30. 
  22. Vedapriya KA, Priyanka D. Morphological variation in azygos vein. Int J Sci Res 2019;8:1396-9. 
  23. Nathan H. Anatomical observations on the course of the azygos vein (vena azygos major). Thorax 1960;15:229-32.  https://doi.org/10.1136/thx.15.3.229
  24. Saito A, Murakami M, Tomioka K, Ezure H, Moriyama H, Mori R, Nakajima K, Nakamura M, Otsuka N. The impact of aging on the course of the azygos vein. Okajimas Folia Anat Jpn 2015;92:7-10.  https://doi.org/10.2535/ofaj.92.7
  25. Kagami H, Sakai H. The problems in the arrangement of the azygos vein. Okajimas Folia Anat Jpn 1990;67:111-4.  https://doi.org/10.2535/ofaj1936.67.2-3_111
  26. Tatar I, Denk CC, Celik HH, Oto A, Karaosmanoglu DA, Ozdemir BM, Surucu SH. Anatomy of the azygos vein examined by computerized tomography imaging. Saudi Med J 2008;29:1585-8. 
  27. Raghavendra AY, Bhosale SM. Variations of arch of azygos vein: an anatomical overview with clinical importance. Int J Anat Res 2017;5:4251-6.  https://doi.org/10.16965/ijar.2017.299
  28. Kutoglu T, Turut M, Kocabiyik N, Ozan H, Yildirim M. Anatomical analysis of azygos vein system in human cadavers. Rom J Morphol Embryol 2012;53:1051-6. 
  29. Patra A, Singla RK, Kaur H, Malhotra V. Analysis of multiple variations in azygos venous system anatomy with its classification: a cadaveric study. Eur J Anat 2019;23:9-15. 
  30. Bass JE, Redwine MD, Kramer LA, Huynh PT, Harris JH Jr. Spectrum of congenital anomalies of the inferior vena cava: cross-sectional imaging findings. Radiographics 2000;20:639-52.  https://doi.org/10.1148/radiographics.20.3.g00ma09639
  31. Milne EN. Some new concepts of pulmonary blood flow and volume. Radiol Clin North Am 1978;16:515-36. 
  32. Chait A. Interstitial pulmonary edema. Circulation 1972;45:1323-30.  https://doi.org/10.1161/01.CIR.45.6.1323
  33. Rossi SE, McAdams HP, Rosado-de-Christenson ML, Franks TJ, Galvin JR. Fibrosing mediastinitis. Radiographics 2001;21:737-57.  https://doi.org/10.1148/radiographics.21.3.g01ma17737
  34. Preger L, Hooper TI, Steinbach HL, Hoffman JI. Width of azygos vein related to central venous pressure. Radiology 1969;93:521-3.  https://doi.org/10.1148/93.3.521
  35. Seema MA. A rare anatomical variation in medial root of azygos vein with its embryological aspect. Int J Anat Sci 2012;3:14-6. 
  36. Dahran N, Soames R. Anatomical variationos of the azygos venous system: classification and clinical relevance. Int J Morphol 2016;34:1128-36.  https://doi.org/10.4067/S0717-95022016000300051
  37. Rao YS, Banerjee A. Anatomical variations of the azygos venous system. Int J Biol Med Res 2014;5:4535-8. 
  38. Keskin S, Keskin Z, Sekmenli N. The independent right and left azygos veins with hemiazygos absence: a rare case presentation. Case Rep Vasc Med 2013;2013:282416. 
  39. Moore KL, Persaud TVN, Torchia MG. Cardiovascular system. In: Torchia MG, Persaud TVN, editors. The Developing Human: Clinically Oriented Embryology. 10th ed. Elsevier; 2016. p.283-334. 
  40. Kc S, Shrestha P, Shah AK, Jha AK. Variations in human pulmonary fissures and lobes: a study conducted in Nepalese cadavers. Anat Cell Biol 2018;51:85-92. https://doi.org/10.5115/acb.2018.51.2.85