SciELO - Scientific Electronic Library Online

vol.34 issue3Descriptive Anatomy of Lateral Digital Extensor Muscles of the Hand of the White-Footed Tamarin (Saguinus leucopus Günther, 1876)Lymphoglandular Complexes in Proximal Colon of Buffalo Calves (Bubalus bubalis) author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google


International Journal of Morphology

On-line version ISSN 0717-9502


DAHRAN, Naief  and  SOAMES, Roger. Anatomical Variations of the Azygos Venous System: Classification and Clinical Relevance. Int. J. Morphol. [online]. 2016, vol.34, n.3, pp.1128-1136. ISSN 0717-9502.

The azygos venous system is highly variable in terms of its origin, course, communications, tributaries and termination of the associated veins: this study aimed to classify these anatomical variations. Thirty Thiel-embalmed cadavers aged 48­98 years (18 female, 12 male) were examined. The vertebral level of termination and diameter of the azygos, hemiazygos, accessory hemiazygos and the left superior intercostal veins were determined, as well as the termination level of the right superior intercostal vein. The azygos system was classified into 3 types; primitive (type 1), transitional (type 2) and unicolumnar (type 3). Type 2 was further divided into 5 subgroups (A to E) according to the number of retroaortic communications. Type one was observed in 3 % (n=1), type 2 in 87 % (n=26) and type 3 in 10 % (n=3) of specimens. The vertebral level of termination of the azygos, hemiazygos, accessory hemiazygos, right superior intercostal and left superior intercostal veins were between T2 and T3, T6 and T10, T5 and T9, T2 and T4, and T2 and T4 respectively. Identification and understanding these variations are important during preoperative radiological investigations and surgical procedures, especially spinal surgery between T7 and T12 using a left thoracotomy approach, to avoid injuries which may lead to postoperative hematomas.

Keywords : Azygos; Hemiazygos; Retroaortic communications; Thiel-embalmed cadavers; Variations.

        · abstract in Spanish     · text in English     · English ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License