PROSPECTIVE ANATOMIC STUDY OF THE INFERIOR VENA-CAVA AND RENAL VEINS - COMPARISON OF SELECTIVE RENAL VENOGRAPHY WITH CAVOGRAPHY AND RELEVANCE IN FILTER PLACEMENT

PURPOSE: To compare the sensitivity of selective renal venography with that of cavography in the detection of variant anatomic structures of the renal vein that may affect the placement of inferior vena caval ( IVC) filters and to define IVC dimensions. PATIENTS AND METHODS: Flush cavography, selective bilateral renal venography, and bilateral iliac venography were performed in 108 patients referred for IVC filter pla cement or vena cavography. Infrarenal IVC length and width were determ ined with a sizing catheter during cavography, Anomalies were consider ed significant if they altered placement or selection of the vena cava l filter or if they represented a potential collateral pathway for clo t to bypass a filter.RESULTS: Variant anatomic structures in the renal vein were found in 11% of patients with cavography and in 37% of pati ents with selective renal vein injection, Detected anomalies included circumaortic veins (n = 11), multiple veins (n = 25), retroaortic vein s (n = 2), and a partially duplicated IVC (n = 1), Selective venograph y depicted anomalies not suspected at standard cavography in 28 cases (26%); in 20 cases (18% of population) they were significant, The aver age infrarenal width was 20 mm on the anteroposterior view and was 17 mm on the lateral projection. CONCLUSION: IVC anomalies are common, an d selective renal venography can depict significant anomalies in renal vein anatomic structures not shown at standard cavography.