PURPOSE Routine low dose non-contrast CT of the abdomen and pelvis has been suggested prior to same day completion CT colonography (CTC) to assess for occult perforation at preceding incomplete colonoscopy, before further gaseous insufflation at CTC. The aim of our study is to examine the incidence of clinically significant perforation at low dose CT. We also examine the benefits of low dose pre-scan in assessing adequacy of bowel preparation and identifying any other relevant contraindications to CT colonography. MATERIALS AND METHODS We conducted a retrospective review of all low dose non-contrast CTs performed following failed colonoscopies over a 4-year period (n = 392). We also assessed the adequacy of bowel preparation on a scale of 1-5, in order of increasingly adequate preparation. Incidentally noted bowel pathology and contraindications to CT colonography were also recorded. RESULTS No perforation was identified either prospectively or in the course of our retrospective review. However, 15 patients (3.8%) were found to have potential contraindications to CT colonography, including: acute diverticulitis, acute colitis, and poor bowel preparation. Overall, the bowel preparation was felt to be adequate (≥ 3) in 86% percent of patients. Two patients (0.5%) identified prospectively had their CT colonography postponed due to poor bowel preparation.

中文翻译：

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低剂量非造影CT穿孔的临床显着穿孔发生率及其在不完全结肠镜检查后当日CT结肠造影之前的价值。

目的建议在当天完成CT结肠成像（CTC）之前，对腹部和骨盆进行常规的低剂量非对比CT检查，以评估先前不完全结肠镜检查之前的隐匿性穿孔，然后在CTC进一步气化。我们研究的目的是检查低剂量CT上具有临床意义的穿孔的发生率。我们还检查了低剂量预扫描在评估肠准备是否充分以及确定CT结肠造影术的其他任何禁忌症方面的益处。材料与方法我们对4年内结肠镜检查失败后进行的所有低剂量非对比CT进行了回顾性研究（n = 392）。我们还以1-5的等级评估了肠道准备的充分性，以使准备工作日趋充足。还记录了肠蠕动和CT结肠造影的禁忌症。结果前瞻性或回顾性研究均未发现穿孔。但是，发现15例患者（3.8％）具有CT结肠造影的潜在禁忌症，包括：急性憩室炎，急性结肠炎和肠道准备不良。总体而言，在86％的患者中，肠道准备被认为是足够的（≥3）。由于肠准备不良，前瞻性确定的两名患者（0.5％）的CT结肠造影检查推迟。和肠道准备不佳。总体而言，在86％的患者中，肠道准备被认为是足够的（≥3）。由于肠准备不良，前瞻性确定的两名患者（0.5％）的CT结肠造影检查推迟。和肠道准备不佳。总体而言，在86％的患者中，肠道准备被认为是足够的（≥3）。由于肠准备不良，前瞻性确定的两名患者（0.5％）的CT结肠造影检查推迟。