X线、CT和超声对胃肠道穿孔诊断价值的再认识

Reappraisal of the diagnostic value of plain radiography, computed tomography and ultrasonography for gastrointestinal perforation

目的:重新评价X线、CT和超声检查(US)在胃肠道穿孔中的应用价值。方法:根据文献资料定义了X线、CT和US诊断胃肠道穿孔的直接和间接征象。回顾性分析284名经手术证实消化道穿孔患者的所有影像学资料,比较3种影像检查的阳性率、穿孔部位和大小与影像征象的关系。结果:X线摄影、CT和US诊断胃肠道穿孔的阳性率分别为75.9%、92.7%和42.1%。立位X线摄影除见膈下游离气体(73.5%)外,还可见其他气腹征(32.8%);卧位X线摄影可见多种气腹征(68.7%)。CT直接征象的显示率为肠壁中断(22.8%)、腹腔游离气体(86.2%)、肠壁外局限性小气泡(68.3%)。US直接征象即腹腔游离气体的显示率为1.8%。X线征象阳性率与穿孔部位、穿孔大小之间差异具有统计学意义,CT和US征象阳性率则无统计学意义。X线摄影的阳性率优于US(P<0.05),而CT则优于X线摄影(P<0.05)。结论:对疑似胃肠道穿孔患者,X线摄影应为首选影像学检查,同时需提高对各种气腹征象的认识。当X线摄影呈阴性表现时应优先考虑US,或根据临床需要辅助定位时选择CT。

Objective To revaluate the diagnostic value of plain radiography, computed tomography (CT) and ultrasonography (US) for gastrointestinal perforation. Methods The direct or indirect signs of gastrointestinal perforation in plain radiography, CT and US were analyzed according to literatures. The imaging data of 284 patients with gastrointestinal perforation confirmed by surgery were reviewed retrospectively. The positive rates of 3 kinds of examinations, namely plain radiography, CT and US, were compared. The relationships between the positive rates of imaging signs and the sites or sizes of gastrointestinal perforation were analyzed. Results The positive rates of plain radiography, CT and US in the diagnosis of gastrointestinal perforation were 75.9%, 92.7% and 42.1%, respectively. Other pneumoperitoneum signs (32.8%) were observed in orthostatic radiograph besides subphrenic free air (73.5%). Moreover, various pneumoperitoneum signs (68.7%) were observed in supine abdominal radiograph. Focal wall disruption (22.8%), free intraperitoneal air (86.2%) and gas bubbles adjacent to the wall (68.3%) were direct signs of gastrointestinal perforation that can be detected by CT examination. The detection rate of free peritoneal air which was the direct sign of gastrointestinal perforation in US was only 1.8%. For plain radiography, there was statistical significance between the positive rates of imaging signs and the sites or sizes of gastrointestinal perforation. However, for CT and US, no statistical significance was found between the positive rates of imaging signs and sites or sizes of gastrointestinal perforation. The positive rate of CT in the diagnosis of gastrointestinal perforation was the highest, followed by plain radiography and then US (all P<0.05). Conclusion For patients with suspected gastrointestinal perforation, plain radiography should be considered as the first choice for imaging examination. Meanwhile, it is necessary to improve the understanding of various pneumoperitoneum signs. If no signs were showed on the plain radiography, US is a preferable choice, and CT should be selected when the image-guided positioning is required in clinic.