the recent development in cross sectional imaging and advanced radiological techniques is an asset in recognising the anomalies of ivc & its tributaries as an incidental finding in asymptomatic patients . the clinical presentation of the patients varies from lower extremity varicose veins , stasis and dermatitis including idiopathic , recurrent deep venous thrombosis since adolescence . the other major clinical complication of this condition may present as retroperitoneal hemorrhage as a result of ruptured collateral vessels or mass effect of the paraspinal collateral circulation . the absence of the infra - renal ivc and the right renal vein is the most severe and infrequent abnormality in anomalies of ivc . awareness of this condition is vital , especially if these individuals are subjected to undergo cardiac procedures via femoral vein access . moreover , an accidental ligation of the right renal collateral may deprive the functions of right kidney . a man in his mid 30 s was referred with complaints of right lower limb pain , swelling , varicose veins with a venous ulcer . he had a past history of perinatal transfusion for erythroblastosis foetalis during his childhood . he has been suffering from right lower limb varices since his childhood and was treated for recurrent episodes of deep venous thrombosis . physical examination revealed multiple large varicose dilatations in right lower limb , collaterals seen in the right anterior and lateral wall of the abdomen . contrast enhanced abdominal computed tomography rendered the hypoplastic renal segment of ivc along with the absence of infra - renal ivc . the absence of the right common iliac vein , right external & internal iliac veins and right proximal common femoral vein was also seen . left external & internal iliac veins drains into the retroperitoneal collaterals due to absence of left common iliac vein . coronal mpr ct image shows hepatic veins ( arrow heads ) seen draining into the intra - hepatic segment of ivc ( arrow ) dilated and tortuous azygous & hemiazygous veins ( fig . coronal mpr ct image shows grossly dilated azygous vein ( arrow ) and hemiazygous vein ( arrow heads ) axial ct image shows collateralization of paraspinal veins ( arrows ) fig 4 . coronal mpr ct image shows massive varices of superficial collateral veins at the abdominal wall . coronal mpr ct image shows a long left renal vein seen draining into the intra - hepatic segment of ivc . 6 coronal mpr ct image shows a right renal collateral vessel draining into hypoplastic segment of ivc . the right renal vein is absent represented by long tortuous collateral draining into hypoplastic segment of ivc ( fig . 6 ) and multiple collaterals draining into the retroperitoneal venous plexus ( fig . 7 ) . the right great saphenous vein exhibits drainage into the distal part of right common femoral vein ( fig . the renal function tests including blood urea , nitrogen and creatinine levels were in normal limits . a concise review of the embryogenesis is recommended to better understand the possible causes of the anomalies of ivc . phillips ( 1 ) has summarised the work of early investigators in a comprehensive manner . the normal inferior vena cava is composed of four segments : hepatic , supra - renal , renal , and infra - renal . the proximal right vitelline vein gives rise to the hepatic sinusoids that derives the hepatic segment . the post - hepatic ivc develops between the sixth and eighth weeks of embryonic life as a composite structure formed from the continuous appearance and regression of three paired embryonic veins , the posterior cardinal , the subcardinal , and the supracardinal veins . the supra - renal segment develops from the right subcardinal vein and the infra - renal segment develops from the right supracardinal vein . persistence of the right postcardinal vein with regression of the supracardinal vein results in the well - known anomaly retrocaval ureter ( 1 ) . the absence of infra - renal ivc is a rare anomaly ( 2 ) . in this anomaly , the developmental insult involves the supracardinal system ( 2 ) . in this patient , neither the right postcardinal vein nor the supracardinal vein persisted . darchambeau ( 3 ) and milner ( 4 ) have proposed that the absence of the infra - renal ivc results from intrauterine or perinatal thrombosis of the ivc and is not of embryonic origin . ( 5 ) , who reported a series of 10 patients with renal vein thrombosis . seven were found during the perinatal period . swaiman et al ( 6 ) suggested that due to the fact that supracardinal veins form last , the supra - renal and renal ivc may form normally from the subcardinal veins , and the infrarenal segment may not develop because of a later insult to the supracardinal veins . but , as bass et al ( 2 ) pointed out , it is true that this construction does not explain the failure of the postcardinal veins to persist , as occurs in retrocaval ureter . however , anomaly of the ivc has been identified as one of the important causes of deep vein thrombosis ( dvt ) in the lower extremities , involving iliac veins , in young patients . this is strongly evidenced by obernosterer et al ( 7 ) and supported by gayer et al ( 8) . the original work of obernosterer reported 31 of 97 patients with dvt , demonstrated thrombotic occlusion of iliac veins . anomalies were missing inferior vena cava , hypoplastic hepatic segment , and missing renal or infra - renal segments with all the five patients being significantly young . in this patient , in addition to the absence of the infra - renal ivc it is represented as a long tortuous vessel that looks more likely as a collateral vessel rather than the actual renal vein . variations of right renal veins are more common than left renal veins ( 9 ) . janschek et al ( 10 ) reported renal vein variations being more common on the right side ( 23% ) than on the left ( 6.7% ) . but none reported a combined absence of infra - renal segment of inferior vena cava with anomalous right renal vein .
various anomalies of the inferior venacava ( ivc ) have been reported in the past . amongst 
 , the absence of ivc is one of the less frequently reported anomalies . 
 the absence can be complete or partial , confined to the hepatic , supra - renal or infra - renal segment of ivc . 
 it is still a controversy , whether these conditions are true embryonic anomalies or the result of perinatal ivc thrombosis.a man in his mid 30 s presented with absence of the infra - renal ivc and both common iliac veins . the right renal vein is replaced by a long tortuous vessel , similar to the appearance of collateral vessel . 
 he presented with extensive varicose veins on the anterior abdominal wall , severe varices of right leg with ulcer . 
 a coronal multiplanar reconstruction ct imaging was used to document the anomaly.prior knowledge of this anomaly is vital , especially if these individuals are subjected to undergo cardiac procedures via femoral vein access .