Acknowledgement
The authors thank Eun Joo Lee of Seoul, South Korea, for her contribution through her illustration (Fig. 1).
References
- Demos TC, Posniak HV, Pierce KL, Olson MC, Muscato M. Venous anomalies of the thorax. AJR Am J Roentgenol 2004;182:1139-1150 https://doi.org/10.2214/ajr.182.5.1821139
- 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
- Dudiak CM, Olson MC, Posniak HV. CT evaluation of congenital and acquired abnormalities of the azygos system. Radiographics 1991;11:233-246 https://doi.org/10.1148/radiographics.11.2.2028062
- 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 https://doi.org/10.1007/s00261-019-01988-3
- 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 https://doi.org/10.1007/s13244-014-0351-3
- Ball JB Jr, Proto AV. The variable appearance of the left superior intercostal vein. Radiology 1982;144:445-452 https://doi.org/10.1148/radiology.144.3.7100455
- Frober R, Eichhorn KH, Schleussner E, Schlembach D. Heterotaxy syndrome: an embryologic study. Ann Clin Lab Res 2016;4:1
- Arslan G, Cubuk M, Ozkaynak C, Sindel T, Luleci E. Absence of the azygos vein. Clin Imaging 2000;24:157-158 https://doi.org/10.1016/S0899-7071(00)00191-1
- 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 https://doi.org/10.1148/radiology.152.1.6729098
- 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 https://doi.org/10.1016/S0894-7317(98)70160-9
- Vaughan TJ, Hawkins IF Jr, Elliott LP. Diagnosis of polysplenia syndrome. Radiology 1971;101:511-518 https://doi.org/10.1148/101.3.511
- Applegate KE, Goske MJ, Pierce G, Murphy D. Situs revisited: imaging of the heterotaxy syndrome. Radiographics 1999;19:837-852; discussion 853-854 https://doi.org/10.1148/radiographics.19.4.g99jl31837
- 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 https://doi.org/10.1007/s00276-015-1454-3
- 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 https://doi.org/10.2214/ajr.156.5.2017954
- 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 https://doi.org/10.1016/j.rmcr.2018.02.001
- 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 https://doi.org/10.1007/s12565-011-0119-5
- 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 https://doi.org/10.1016/j.athoracsur.2013.10.029
- Savu C, Melinte A, Balescu I, Bacalbasa N. Azygos vein aneurysm mimicking a mediastinal mass. In Vivo 2020;34:2135-2140 https://doi.org/10.21873/invivo.12019
- Tujo CA, Jesinger RA. Azygous vein aneurysm (AVA): a case report. J Clin Diagn Res 2017;11:TD03-TD05 https://doi.org/10.7860/JCDR/2017/20945.9421
- 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 https://doi.org/10.3348/kjr.2011.12.6.754
- 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 https://doi.org/10.1016/j.crad.2015.06.077
- Gebrael J, Yu H, Hyslop WB. Spontaneous portoazygos shunt in a patient with portal hypertension. J Radiol Case Rep 2013;7:32-36
- 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 https://doi.org/10.2214/ajr.167.5.8911174
- Cai SF, Gai YH, Liu QW. Computed tomography angiography manifestations of collateral circulations in Budd-Chiari syndrome. Exp Ther Med 2015;9:399-404 https://doi.org/10.3892/etm.2014.2125
- Erden A. Budd-Chiari syndrome: a review of imaging findings. Eur J Radiol 2007;61:44-56 https://doi.org/10.1016/j.ejrad.2006.11.004
- 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 https://doi.org/10.2214/ajr.171.5.9798887
- 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 https://doi.org/10.1148/rg.301095724
- 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 https://doi.org/10.1148/83.3.419
- 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 https://doi.org/10.1016/j.radcr.2021.04.061
- Smillie RP, Shetty M, Boyer AC, Madrazo B, Jafri SZ. Imaging evaluation of the inferior vena cava. Radiographics 2015;35:578-592 https://doi.org/10.1148/rg.352140136
- 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 https://doi.org/10.4297/najms.2011.3435