図１〜図４で肝臓と脾臓周囲に腹水（※）があるが，量としては500〜600ml 程度で，図９でIVCは大動脈より大きめだから循環血液量不足はない．図１〜図３の△は右門脈前区域枝（rapv）の連続で，図９〜図１２の△は右門脈後区域枝（rppv）の枝であり，出血量と図９のIVCの大きさを考慮すればextravasationではないと考えるが，その判断にはdouble phase造影CTがほしいところである．図１〜図１２の肝右葉の大部分を占め，低吸収値を呈する▲は血流のない肝組織であり，造影される肝組織とは明瞭に境界される．ややdensityの高い部分は血腫を形成していると思われ，外傷性肝壊死と診断する．図A〜図Dの5日後のCTで，血流のない部分にガスが発生し（↑）肝壊死を裏付ける所見である．Hbは15.3g/dlから最低11.6g/dlまでの低下にとどまった．第10病日に総ビリルビン値が11.9mg/dlまで上昇し続けたので肝右葉部分切除を行った．病理：liver necrosis．

文献考察：外傷性肝壊死
Hatten MT, Hamrick-Turner JE.
Segmental hepatic necrosis after blunt abdominal trauma: CT findings.
AJR Am J Roentgenol. 1996 Sep;167(3):769-70. PMID: 8751697
追記：16歳男性，腹部鈍的外傷による肝左葉損傷があり，CTで外側区域が境界鮮明な低吸収域を示した．5日目に腹痛を訴え，ビリルビンが2．5mg/dlと上昇し，CTで左葉外側区域にガス発生を認め，手術で同部の肝壊死を認めた．ガス発生機序については言及されていない．

Dig Surg. 2000;17(6):595-601.
Traumatic and postoperative ischemic liver necrosis: causes, risk factors and treatment.
Rokke O, Nesvik I, Sondenaa K.

BACKGROUND: To study the cause and outcome of ischemic liver necrosis and suggest treatment of these patients. METHODS: Retrospective study of 13 patients with ischemic liver necrosis treated at our departments from 1990 until 1997. RESULTS: Ischemic liver necrosis was caused by general hypoxia (n = 1) or acute arterial occlusion (n = 12) of the celiac and superior mesenteric artery (SMA, n = 3), proper hepatic artery (PHA, n = 1), right hepatic artery (RHA, n = 2), left hepatic artery (LHA, n = 2) and intrahepatic vessels (n = 4). Six of the cases were related to surgical procedures, 5 of these (38%) were unintended arterial injuries after biliary surgery. Ten patients (77%) had risk factors contributing to the development of liver necrosis: septicemia (n = 4), jaundice and septicemia (n = 2), shock and hypoxia (n = 3) and alcoholic cirrhosis (n = 1). Five patients (38%) needed resection of the liver necrosis due to infected necrosis. Three patients (23%) died; two of these had celiac/SMA occlusion. One died due to complete gastrointestinal ischemia and severe lactacidosis, two died of multiorgan failure after bile leakage and septicemia. CONCLUSION: Ischemic liver necrosis is mainly caused by arterial occlusion due to arteriosclerosis, arterial transection during biliary surgery or blunt liver trauma, and seldom occurs without additional risk factors. 50% of the patients develop infected necrosis and need liver resection. Patients with sterile necrosis may recover without surgical procedures of the liver. The mortality in patients with central (celiac/SMA) and peripheral (CHA, PHA, RHA, LHA, intrahepatic branches) occlusions was 67% (2/3) and 11% (1/9), respectively. PMID: 11155005