Inferior vena cava anomalies and variations: imaging and rare clinical findings

Abstract

Purpose: The aim of this paper is to summarize imaging findings of some frequent and infrequent inferior vena cava (IVC) anomalies and variations.

Conclusions: IVC anomalies should be suspected in patients presenting with pulmonary emboli, chronic pain, and deep vein thrombosis. To correctly characterize and classify IVC anomalies and variations is of crucial importance for proper planning of surgical interventions and thus for avoiding serious complications.

Key points: • IVC anomalies should be suspected in patients with pulmonary emboli, pain, and venous thrombosis. • Awareness of IVC anomalies and variations is crucial for clinical and surgical procedures. • Unawareness of these anomalies may lead to severe and deadly complications.

Keywords: IVC; Inferior vena cava anomalies; Inferior vena cava variations; Magnetic resonance imaging; Multidetector row computed tomography.

Fig. 1

a Coronal maximum-intensity-projection (MIP) MDCT image showing elongated and tortuous suprarenal IVC segment (open arrow) progressing with intrahepatic IVC segment b Axial MDCT image showing concurrent CA (asterisk)/CHA (arrow) at the base of the heart c Coronal MDCT image showing CHA draining into CA approximately at the level of thoracal 6 (T6) (arrow) d Coronal MDCT image showing retrocrural shunts (arrows) secondary to IVC agenesis

Fig. 2

a Coronal MIP MDCT image showing an appearance of complete thrombosis of the infrarenal portion of IVC (on the right (arrow) and tortuous appearance of gonadal vein (median pathway) (on the left) (asterisk) b Coronal MIP MDCT image showing enlarged inferior hemorrhoidal vein (portal pathway) (arrow) c Sagittal MIP MDCT image showing ascending lumbar veins with an appearance of pseudomasses at the level of lumbar vertebra (deep pathway) (arrow) d Coronal MPR MRI image showing infrarenal IVC agenesis (arrow) (e) Coronal MPR MRI image showing enlarged epigastric vein (superficial pathway) (arrow)

Fig. 3

Illustration of findings of infrarenal IVC agenesis with collateral pathways including superficial (epigastric vein, internal mammarian veins, thoracoabdominal veins, lateral thoracic vein and axillary vein), portal (inferior haemorrhoidal vein (IHV), paraumbilical veins (PUV), inferior mesenteric vein (IMV)), deep (ascending lumbar vein, continuous azygos vein (CA), continuous hemiazygos vein (CHA)), and median collateral pathways (gonadal vein). (RA: right atrium; A: aorta; SVC: superior vena cava; RRV and LRV: right and left renal veins, respectively; D: diaphragm)

Fig. 4

a Coronal MIP MDCT image showing CHA draining into CA at the level of T8-9 (arrow) b Axial MIP MDCT image showing CHA draining into CA at the level of T8-9(arrow)

Fig. 5

a Coronal MIP MDCT image showing left IVC (arrow) associated with dilated right gonadal vein (on the right) (asterisk) b Coronal MIP MDCT image showing RRV (small arrow) draining into the retroaortic left IVC (large arrow) in the paravertebral area, the dilated right gonadal vein is marked with an asterix

Fig. 6

a Coronal MPR MDCT image showing enlarged inferior mesenteric vein (arrow) draining into the portal vein (asterisk) b Axial MDCT image showing RRV (arrow) draining into the left IVC (asterix) anterior to the aorta

Fig. 7

Illustration of findings of left IVC (LIVC) with continuous azygos (CA) and hemiazygos (CHA) veins. Note drainage of a dilated gonadal vein (GV) to the right renal vein (median collateral pathway). Ascending lumbar veins (deep pathway) are draining into CA and CHA. (RA: right atrium; A: aorta; SVC: superior vena cava; RRV and LRV: right and left renal veins, respectively; CIV: common iliac veins; D: diaphragm)

Fig. 8

a Coronal MIP MDCT image showing parallel elongated segments of CHA(white arrow) and CA (black arrow) with concurrent right (asterix) and left IVC (arrow head) in the infrarenal segment b Axial MIP MDCT image showing left IVC (arrow head) draining into the LRV (white arrow)and the right IVC (black arrow) into the RRV (black asterix) at the renal level c Coronal MIP MDCT image showing hemiazygos vein (white arrow) joining azygos (White asterix) at the level of T6 and its progress

Fig. 9

a Coronal MIP MDCT image showing concurrent appearance of right (arrow) and left IVC in the infrarenal segment (asterix) b Coronal MIP MDCT image showing left IVC joining the right IVC (arrow) at the renal level and right IVC draining into the right atrium following the intrahepatic segment (asterix)

Fig. 10

Illustration of findings of double IVC. Note that the right renal vein (RRV) and left renal vein (LRV) drain to the right inferior vena cava (RIVC) and the left inferior vena cava (LIVC), respectively. The continuous hemiazygos vein (CHA) joins the continuous azygos vein (CA) suprediaphragmatically. Ascending lumbar veins drain to the CA and the CHA (deep collateral pathway). (RA: right atrium; A: aorta; SVC: superior vena cava; CIV: common iliac vein; D: diaphragm)

Fig. 11

a Coronal MDCT image showing interruption of the IVC and its continuation with azygos vein (arrow); aorta is marked with an asterix b Coronal MPR MDCT image showing normal IVC (on the right) (asterix) with associated splenosis (arrows); aorta is marked with a small white circle c Axial MDCT image showing retroaortic LRV joining the right IVC (arrow)

Fig. 12

Illustration of findings of interrupted IVC (RIVC) and its continuation with azygos vein (CA). Right renal vein (RRV) and retroaortic left renal vein (LRV) drain to CA (RA: right atrium; A: aorta; SVC: superior vena cava; CIV: common iliac vein; D: diaphragm)

Fig. 13

a Axial MDCT image showing retroaortic LRV Type I joining the IVC b Coronal MDCT image showing left retroaortic vein joining the IVC (black arrow)

Fig. 14

a Coronal MDCT MPR image showing accessory CHA progressing in the left paramedian area (arrow) b Sagittal MDCT MPR image showing accessory CHA (arrow) c Axial MDCT MPR image showing the segment of accessory CHA (arrow) joining the brachiocephalic trunk (asterix)