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CT Findings of Azygos Venous System: Congenital Variants and Acquired Structural Changes

기정맥계의 CT 소견: 선천변이 및 후천적 구조 변화

  • Ha Neul Kim (Department of Radiology, Hanyang University College of Medicine, Hanyang University Guri Hospital) ;
  • Youkyung Lee (Department of Radiology, Hanyang University College of Medicine, Hanyang University Guri Hospital) ;
  • Su Jin Hong (Department of Radiology, Hanyang University College of Medicine, Hanyang University Guri Hospital) ;
  • Ji Hun Kang (Department of Radiology, Hanyang University College of Medicine, Hanyang University Guri Hospital) ;
  • Ji-hoon Jung (Department of Radiology, Hanyang University College of Medicine, Hanyang University Guri Hospital)
  • 김하늘 (한양대학교 의과대학 한양대학교 구리병원 영상의학과) ;
  • 이유경 (한양대학교 의과대학 한양대학교 구리병원 영상의학과) ;
  • 홍수진 (한양대학교 의과대학 한양대학교 구리병원 영상의학과) ;
  • 강지훈 (한양대학교 의과대학 한양대학교 구리병원 영상의학과) ;
  • 정지훈 (한양대학교 의과대학 한양대학교 구리병원 영상의학과)
  • Received : 2023.06.27
  • Accepted : 2023.10.04
  • Published : 2024.01.01

Abstract

The azygos venous system is a crucial conduit of the posterior thorax and potentially vital collateral pathway. However, it is often overlooked clinically and radiologically. This pictorial essay reviews the normal azygos venous anatomy and CT findings of congenital variations and structural changes associated with acquired pathologies.

기정맥계는 후방 흉부의 중요한 부속 정맥이며 측부순환으로서 중대한 역할을 한다. 그러나, 그 중요성에도 불구하고 임상적 혹은 영상의학적으로 종종 간과된다. 본 임상화보에서는, 기정맥계의 정상 해부학에 대해 알아보고, 기정맥계에서 볼 수 있는 다양한 선천 변이와 후천적 질환에 따른 구조 변화의 CT 소견에 대하여 검토하고자 한다.

Keywords

Acknowledgement

The authors thank Eun Joo Lee of Seoul, South Korea, for her contribution through her illustration (Fig. 1).

References

  1. Demos TC, Posniak HV, Pierce KL, Olson MC, Muscato M. Venous anomalies of the thorax. AJR Am J Roentgenol 2004;182:1139-1150
  2. Tatar I, Denk CC, Celik HH, Oto A, Karaosmanoglu DA, Ozdemir BM, et al. Anatomy of the azygos vein examined by computerized tomography imaging. Saudi Med J 2008;29:1585-1588
  3. Dudiak CM, Olson MC, Posniak HV. CT evaluation of congenital and acquired abnormalities of the azygos system. Radiographics 1991;11:233-246
  4. Shin DS, Sandstrom CK, Ingraham CR, Monroe EJ, Johnson GE. The inferior vena cava: a pictorial review of embryology, anatomy, pathology, and interventions. Abdom Radiol (NY) 2019;44:2511-2527
  5. Piciucchi S, Barone D, Sanna S, Dubini A, Goodman LR, Oboldi D, et al. The azygos vein pathway: an overview from anatomical variations to pathological changes. Insights Imaging 2014;5:619-628
  6. Ball JB Jr, Proto AV. The variable appearance of the left superior intercostal vein. Radiology 1982;144:445-452
  7. Frober R, Eichhorn KH, Schleussner E, Schlembach D. Heterotaxy syndrome: an embryologic study. Ann Clin Lab Res 2016;4:1
  8. Arslan G, Cubuk M, Ozkaynak C, Sindel T, Luleci E. Absence of the azygos vein. Clin Imaging 2000;24:157-158
  9. Milne EN, Pistolesi M, Miniati M, Giuntini C. The vascular pedicle of the heart and the vena azygos. Part I: the normal subject. Radiology 1984;152:1-8
  10. Blanchard DG, Sobel JL, Hope J, Raisinghani A, Keramati S, DeMaria AN. Infrahepatic interruption of the inferior vena cava with azygos continuation: a potential mimicker of aortic pathology. J Am Soc Echocardiogr 1998;11:1078-1083
  11. Vaughan TJ, Hawkins IF Jr, Elliott LP. Diagnosis of polysplenia syndrome. Radiology 1971;101:511-518
  12. Applegate KE, Goske MJ, Pierce G, Murphy D. Situs revisited: imaging of the heterotaxy syndrome. Radiographics 1999;19:837-852; discussion 853-854
  13. Del Prete A, Cavaliere C, Di Pietto F, De Ritis R. Situs inversus with levocardia, infrahepatic interruption of the inferior vena cava, and azygos continuation: a case report. Surg Radiol Anat 2016;38:369-371
  14. Mata J, Caceres J, Alegret X, Coscojuela P, De Marcos JA. Imaging of the azygos lobe: normal anatomy and variations. AJR Am J Roentgenol 1991;156:931-937
  15. Akhtar J, Lal A, Martin KB, Popkin J. Azygos lobe: a rare cause of right paratracheal opacity. Respir Med Case Rep 2018;23:136-137
  16. Ndiaye A, Ndiaye NB, Ndiaye A, Diop M, Ndoye JM, Dia A. The azygos lobe: an unusual anatomical observation with pathological and surgical implications. Anat Sci Int 2012;87:174-178
  17. Ko SF, Huang CC, Lin JW, Lu HI, Kung CT, Ng SH, et al. Imaging features and outcomes in 10 cases of idiopathic azygos vein aneurysm. Ann Thorac Surg 2014;97:873-878
  18. Savu C, Melinte A, Balescu I, Bacalbasa N. Azygos vein aneurysm mimicking a mediastinal mass. In Vivo 2020;34:2135-2140
  19. Tujo CA, Jesinger RA. Azygous vein aneurysm (AVA): a case report. J Clin Diagn Res 2017;11:TD03-TD05
  20. Yang JY, Kim DH, Lee JH, Suk EH. Evaluating a thrombosed azygous vein aneurysm combined with pulmonary arterial thromboembolism by ECG-gated multidetector CT: a case report. Korean J Radiol 2011;12:754-756
  21. Pillai AK, Andring B, Patel A, Trimmer C, Kalva SP. Portal hypertension: a review of portosystemic collateral pathways and endovascular interventions. Clin Radiol 2015;70:1047-1059
  22. Gebrael J, Yu H, Hyslop WB. Spontaneous portoazygos shunt in a patient with portal hypertension. J Radiol Case Rep 2013;7:32-36
  23. Cho OK, Koo JH, Kim YS, Rhim HC, Koh BH, Seo HS. Collateral pathways in Budd-Chiari syndrome: CT and venographic correlation. AJR Am J Roentgenol 1996;167:1163-1167
  24. Cai SF, Gai YH, Liu QW. Computed tomography angiography manifestations of collateral circulations in Budd-Chiari syndrome. Exp Ther Med 2015;9:399-404
  25. Erden A. Budd-Chiari syndrome: a review of imaging findings. Eur J Radiol 2007;61:44-56
  26. Dahan H, Arrive L, Monnier-Cholley L, Le Hir P, Zins M, Tubiana JM. Cavoportal collateral pathways in vena cava obstruction: imaging features. AJR Am J Roentgenol 1998;171:1405-1411
  27. Kapur S, Paik E, Rezaei A, Vu DN. Where there is blood, there is a way: unusual collateral vessels in superior and inferior vena cava obstruction. Radiographics 2010;30:67-78
  28. Berk RN. Dilatation of the left superior intercostal vein in the plain-film diagnosis of chronic superior vena caval obstruction. Radiology 1964;83:419-423
  29. Picascia O, Fiorini V, Vitale G, Quassone P, Scognamiglio M, Ferrandino G, et al. Iatrogenic superior vena cava syndrome with concomitant deep vein thrombosis of azygos and hemiazygos veins. Radiol Case Rep 2021;16:1895-1898
  30. Smillie RP, Shetty M, Boyer AC, Madrazo B, Jafri SZ. Imaging evaluation of the inferior vena cava. Radiographics 2015;35:578-592
  31. Vallakati A, Chandra PA, Frankel R, Shani J. Intra-atrial tumor thrombi secondary to hepatocellular carcinoma responding to chemotherapy. N Am J Med Sci 2011;3:435-437