Unusual coexistence of double inferior vena cava with nutcracker syndrome-a case report and review of the literature.

Knowledge of vessel anomalies is significant for all specialists in clinical practice and may prevent serious complications following medical interventions. Here, the rare coexistence of a duplicated inferior vena cava (IVC) and nutcracker syndrome in a 42-year-old female patient with atypical abdominal pain is presented, using two complementary radiological techniques (colour Doppler ultrasonography and computed tomography angiography). The right renal vein was found to be compressed when passing between the superior mesenteric artery and the abdominal aorta. The lumen dimensions (width × height) of the right IVC and left IVC at the level of termination were 15.8 × 17.7 mm and 13.4 × 12.4 mm, respectively. Ultrasonography revealed low blood flow in the left IVC that was reversed, and thus blood travelled in the same caudal direction as in the aorta. In the right IVC, however, flow travelled in the cranial direction. The simultaneous existence of a duplicated IVC and nutcracker syndrome is an extremely rare vessel anomaly; nevertheless, this dual presence may result in clinical symptoms and would have an impact on medical operations and even minor medical procedures.