Isolated Thrombosis of Left-sided Vena Cava


Knowledge of vascular anomalies can prevent confusion with pathologic masses. Bilateral vena cava is noted as an incidental finding on CT scans in approximately 0.3% of cases [1]. We have recently encountered a case in which isolated thrombus in the left side of a duplicated system was initially mistaken for adenopathy.

A 62-year-old female presented with atypical right upper quadrant pain. Physical exam, laboratory tests, gallbladder ultrasound, and upper and lower gastrointestinal series were normal. CT of abdomen showed a left paraaortic mass which extended from the renal hilus to the aortic bifurcation (Fig. 1a). Smaller retroperitoneal nodes were also evident. Biopsy of the mass revealed clot and atypical lymphocytes. The patient became less symptomatic with time and without specific treatment. Subsequent scans showed that the "mass" was decreasing in size. Six months after initial presentation a CT scan of abdomen showed a smooth enhancing tubular structure extending from the left renal vein to the bifurcation consistent with a vascular structure, i.e., left-sided vena cava (Fig. 1b).

CT criteria for venous thrombosis have been described: enlargement of the thrombosed vein, a low-density central lumen, and a sharply defined enhancing wall [2]. In our case the central hypodensity was confused with necrosis. Associated smaller retroperitoneal adenopathy also delayed recognition of this thrombosed vascular anomaly, which has not been reported previously.

Jeffrey C. Allard H. Scott Harris

University of Miami School of Medicine PO Box 016960 (R-109) Miami, FL 33101

References

1. Mayo J, Gray R, St. Loius E, Grossman H, McLoughlin M, Wise D. Anomalies of the inferior vena cava. AJR 1983;140:339-345

2. Zerhouni EA, Barth KA, Siegelman SS. Demonstration of venous thrombosis by computed tomography. AJR 1980; 134:753-758











Figure legends«)0»



Figure 1a. There is a 1 cm aortocaval node (thick arrow) and a 2.5 cm left paraaortic structure (thin arrow).

«)@»



Figure 1b. The aortocaval node is smaller and the left paraaotic structure (arrow) is shown to be tubular and enhance homogeneously.«)A»