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Absence of the infrarenal inferior vena cava with preservation of the suprarenal segment as revealed by CT and MR venography.

C omplete absence of the infrarenal (postrenal) segment of the inferior vena cava (IVC) is a rare anomaly. To our knowledge. 14 cases proven by imaging have been described in the English Ianguage medical literature since 1957 [ 1-7]. Of these, only one report also described persistence of the suprarenal (prerenal) segment [11. Unlike the more common azygous continuation of the IVC, which can be found incidentally in asymptomatic patients [2], complete absence of the infrarenal IVC may be associated with significant clinical manifestations. We believe this to be the second reported case of absence of the infrarenal segment of the IVC with preservation of the suprarenal segment to be shown by diagnostic imaging and the first depicted by MR venography.