右腎は造影効果を受けず，血流のない状態である．IVC周囲（右腎門部周囲）から対側の腎周囲腔に拡がる大きな後腹膜腔内血腫を認め，右腎茎部血管損傷を強く示唆する．図１と図２の▲は腎実質内に位置し，extravasationではなく周囲の側副路から造影された実質であろう．図６〜図８の△は腎の辺縁に位置し，造影された腎実質かextravasationか不明である．図６でIVCが2つに分かれて下行し（白矢印と↑），図１４でまた合流する．先天異常の部分的なdouble IVCか，どちらかがIVCで他方はextravasationかの判断もdouble phase造影CTが必要である．Extravasationならdelayed phaseで拡散し，変形増大するので鑑別が可能になる．腎茎部血管損傷による出血と壊死に陥った右腎の診断で緊急手術が施行された．右腎動脈が大動脈から分岐する部位で完全断裂しており，腎臓は壊死に陥っていた．

文献考察：腎外傷2467例．
J Trauma. 2001 Feb;50(2):195-200.
Validation of the American Association for the Surgery of Trauma organ injury severity scale for the kidney.
Santucci RA, McAninch JW, Safir M, Mario LA, Service S, Segal MR.

BACKGROUND: We queried an observational database of renal trauma patients to validate the organ injury severity scale (kidney) of the American Association for the Surgery of Trauma (AAST). METHODS: In a retrospective review of our renal trauma database (2,467 patients) with 58 clinical and radiographic patient variables, statistical "classification trees" were used to determine factors predicting need for surgical repair. RESULTS: Scales correlated with the need for surgery (grade I = 0%, grade II = 15%, grade III = 76%, grade IV = 78%, and grade V = 93%) and for nephrectomy (grade I = 0%, grade II = 0%, grade III = 3%, grade IV = 9%, and grade V = 86%). Classification tree analysis (confirmed in 83 additional patients) identified the AAST organ injury severity scale as the most important variable predicting the need for renal repair. CONCLUSION: In a retrospective review of more than 2,500 patients, we determined that the AAST organ injury severity scale correlates with the need for kidney repair or removal. Classification tree analysis confirmed the scale as the prime variable predicting need for surgical repair.PMID: 11242281