図６〜図１８で下行結腸(D）と▲の空腸は壁の造影効果を認めるからviableで，以外の腸管は造影効果がないか極めて弱く虚血状態にあると思われる．図１〜図８で図６の横行結腸（T1）までは良好な壁の造影効果を認めるが，図６のT2から右側は造影効果が減弱する．SMAは図９で造影されなくなり（↑），心房細動があることからSMA塞栓症である．図Aの血管造影でSMAの血流途絶を認めた（↑）．ウロキナーゼを動注したが効果が無いため，術前から塩酸パパベリンの持続動注を開始し手術を施行した．回腸約200cmと上行結腸中央部まで壊死に陥っており切除したが，小腸はTreitz靱帯から110cmがviableで，術前から塩酸パパベリンを持続動注を行った効果（viableかnonviableか不明なボーダーラインの腸管がviableとなる）が認められたと思われる症例である．

参考症例（上腸間膜動脈塞栓症）：59歳男性．1ヶ月前に不整脈と糖尿病を指摘された．1時間前に上腹部痛と嘔吐が出現し来院した．腹部はsoft and flatで心窩部に圧痛があるのみ．図５でSMAが造影されなくなり（↑），図２で△は脾梗塞の可能性を示唆し塞栓症である．図１０で▲の小腸と下行結腸(D）以外の腸管は壁の造影効果が弱く虚血状態に陥っている可能性が高い．CT所見を見落とされ，翌日のCT再検査でSMA塞栓症を疑い血管造影が行われ，図AでSMAのかなり中枢側で血流途絶を示している（↑）．手術で全小腸，上行結腸と横行結腸が壊死に陥っていた（図B）．

文献考察1)：MDCTによる急性腸管虚血症の診断率は高い．
Eur Radiol. 2004 Dec;14(12):2347-56. Epub 2004 Sep 17.
Accuracy of multidetector row computed tomography for the diagnosis of acute bowel ischemia in a non-selected study population.
Wiesner W, Hauser A, Steinbrich W.

The diagnostic accuracy of multidetector row computed tomography for the prospective diagnosis of acute bowel ischemia in the daily clinical routine was analyzed. Two hundred ninety-one consecutive patients with an acute or subacute abdomen, examined by MDCT over a time period of 5 months, were included in the study. All original CT diagnoses made during the daily routine by radiological generalists were compared to the final diagnoses made by using all available medical information from endoscopies, surgical interventions, autopsies and follow-up. Finally, all CT examinations of patients with an initial CT diagnosis or a final diagnosis of bowel ischemia were reread by a radiologist specialized in abdominal imaging in order to analyze the CT findings and the reasons for initially false negative or false positive CT readings. Twenty-four patients out of 291 (8.2%) had acute bowel ischemia. The age of affected patients ranged from 50 to 94 years (mean age: 75.7 years). Eleven patients were male, and 13 female. Reasons for acute bowel ischemia were: arterio-occlusive (n=11), non-occlusive (n=5), strangulation (n=2), over-distension (n=3) and radiation (n=3). The prospective sensitivity, specificity, PPV and NPV of MDCT for the diagnosis of acute bowel ischemia in the daily routine were 79.17, 98.51, 90.48 and 98.15%. MDCT reaches a similarly high sensitivity in diagnosing acute bowel as angiography. Furthermore, it has the advantage of being helpful in most of its clinical differential diagnoses and of being less invasive with the consecutive possibility of being used earlier in the diagnostic process with all the resulting positive effects on the patients prognosis. Therefore, nowadays MDCT should probably be used as the first step imaging modality of choice in patients with suspected acute bowel ischemia.PMID: 15378337

文献考察２）：MDCTによる急性腸間膜虚血症の診断はsensitivity 96%，specificity 94%の精度が得られる．
Radiology. 2003 Oct;229(1):91-8. Epub 2003 Aug 27.
Biphasic CT with mesenteric CT angiography in the evaluation of acute mesenteric ischemia: initial experience.
Kirkpatrick ID, Kroeker MA, Greenberg HM.

PURPOSE: To evaluate the sensitivity and specificity of biphasic computed tomography (CT) with mesenteric CT angiography in the diagnosis of acute mesenteric ischemia (AMI). MATERIALS AND METHODS: Sixty-two patients with clinically suspected AMI underwent prospective imaging with biphasic multi-detector row CT. Mesenteric CT angiography was performed with 1.25-mm collimation starting 25 seconds after 140 mL of intravenous contrast agent was administered at a rate of 4 mL/sec, followed by portal venous phase imaging with 5-mm collimation and a 60-70-second delay. CT angiograms were reconstructed with multiplanar (including transverse), maximum intensity projection, and volume-rendered techniques. All scans were evaluated prospectively by two independent radiologists for CT evidence of ischemia. AMI was confirmed with surgical or pathologic proof in 25 of 26 patients. In one patient, AMI was confirmed with clinical findings and serial CT examinations. In patients with AMI, sensitivity and specificity of each CT sign were calculated retrospectively by using patients who did not have intestinal ischemia as a control group. CT criteria that optimized sensitivity and specificity for the diagnosis of AMI were then developed. RESULTS: AMI was diagnosed in 26 patients. The CT angiogram depicted arterial disease in eight patients and altered care in five. A finding of any one of pneumatosis intestinalis, venous gas, superior mesenteric artery occlusion, celiac and inferior mesenteric artery occlusion with distal SMA disease, or arterial embolism was 100% specific but only 73% sensitive. Alternatively, a finding of bowel wall thickening in addition to focal lack of bowel wall enhancement, solid organ infarction, or venous thrombosis was 50% sensitive and 94% specific. By using either of these criteria for the diagnosis, a sensitivity of 96% and a specificity of 94% can be achieved. CONCLUSION: Biphasic CT with mesenteric CT angiography is effective in the diagnosis of AMI. PMID: 12944600（full text）