Rossi G, Grassi R, Pinto A, Ragozzino A, Romano L
Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Napoli.
Radiol Med. 1998 May;95(5):474-80.
We retrospectively reviewed the CT findings of the acute abdomen patients examined in the last two years to investigate the frequency of a new CT sign of intestinal infarction, the pneumoretroperitoneum, and its association with other CT findings highly suggestive of this condition.
The CT findings of 60 patients with diagnostic confirmation of intestinal infarction were retrospectively reviewed. CT was performed without (no. = 55) and with (no. = 5) oral administration of contrast material and without (no. = 3) and with (no. = 57) the i.v. injection of nonionic contrast agents in repeated 50 mL boluses. To assess the specificity of this sign, we selected a control group of 400 patients submitted to CT for acute abdomen, but not blunt trauma; 19 of these patients had pneumoretroperitoneum.
Pneumoperitoneum was found in five patients with intestinal infarction; it was an isolated sign in two cases and it was associated with few small perihepatic air bubbles in one case. Finally, it was associated with highly suggestive findings of late intestinal infarction in the other two cases. All cases of pneumoretroperitoneum in the control group had been correctly referred to other diseases by previous plain film and/or CT findings and surgery and/or endoscopy confirmed this diagnosis.
Pneumoretroperitoneum has been described as a complication of different benign or severe disorders; prompt recognition of its origin is essential since surgical and/or septic conditions may be involved. However, if the patient's history is negative for abdominal trauma, gastroduodenal ulcer or sepsis, pneumoretroperitoneum is generally cured with conservative treatment. Intestinal infarction or severe ischemia, a usually surgical conditions, should be considered among the different causes of pneumoretroperitoneum alone or associated with pneumoperitoneum or with highly suggestive late findings of infarction such as portal venous gas or pneumatosis intestinalis. This sign had a non-negligible incidence in intestinal infarction in our review (8.5%), but it should be known of and sought with specific window setting to enhance gas depiction on CT images to avoid false negatives.
我们回顾性分析了过去两年中接受检查的急腹症患者的CT表现，以研究肠梗死新的CT征象——腹膜后积气的出现频率，及其与其他高度提示该病症的CT表现之间的关联。
回顾性分析60例经诊断证实为肠梗死患者的CT表现。5名患者口服对比剂后进行CT检查（共5例），55名患者未口服对比剂；3名患者静脉注射非离子型对比剂后进行CT检查（共57例），每次静脉推注50ml。为评估该征象的特异性，我们选择了400例因急腹症接受CT检查但未受钝性创伤的患者作为对照组；其中19例患者存在腹膜后积气。
5例肠梗死患者发现有气腹；2例为孤立征象，1例伴有少量肝周小气泡。最后，另外2例与晚期肠梗死的高度提示性表现相关。对照组中所有腹膜后积气病例均根据先前的平片和/或CT表现正确诊断为其他疾病，手术和/或内镜检查证实了这一诊断。
腹膜后积气已被描述为不同良性或严重疾病的并发症；由于可能涉及手术和/或感染情况，迅速识别其来源至关重要。然而，如果患者无腹部创伤、胃十二指肠溃疡或败血症病史，腹膜后积气通常采用保守治疗。在腹膜后积气单独出现或与气腹或梗死的高度提示性晚期表现（如门静脉积气或肠壁积气）相关的不同病因中，应考虑肠梗死或严重缺血，这通常是需要手术治疗的情况。在我们的研究中，该征象在肠梗死中的发生率不可忽视（8.5%），但应了解并通过特定的窗口设置寻找该征象，以增强CT图像上气体的显示，避免漏诊。
