Vena Cava Duplications

Image 1 - Duplication of inferior vena cava.
This is a not uncommon variation. The left sided IVC (black arrow) most commonly ends in the normal left renal vein.
Image 2 - Duplication of superior vena cava.
This is a rare variation of the SVC. The left sided SVC (white arrow) is draining into the left atrium, thereby bypassing the pulmonary circulation. The right SVC is normal.
References:
1. J. Edward Bass, Michael D. Redwine et al. Spectrum of Congenital Anomalies of the Inferior Vena Cava: Cross-sectional Imaging Findings. RadioGraphics 2000; 20: 639.
2. GM Kellman, MB Alpern, MA Sandler, and BM Craig. Computed tomography of vena caval anomalies with embryologic correlation. RadioGraphics 1988; 8: 533.
Credit: Dr Abhijit Datir
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