非对比增强CT对临床疑诊急性阑尾炎的诊断准确性（附74例分析）

目的评价非对比增强CT对1临床疑诊急性阑尾炎的诊断准确性。方法74例临床疑诊急性阑尾炎患者均经非对比增强的腹盆部（从L1椎体水平至耻骨联合上缘）螺旋CcT扫描。用于诊断急性阑尾炎的标准为阑尾直径大于6mm和阑尾周围脂肪的炎性改变。最终的CT诊断经手术或临床随访证实。结果74例临床疑诊急性阑尾炎患者中，CT诊断25例真阳性，42例真阴性，4例假阴性和3例假阳性，敏感性为86．2％，特异性为93．3％，准确性为90．5％，阳性预测值为89．3％，阴性预测值为91．3％。结论非对比增强CT对诊断或排除急性阑尾炎具有较高的准确性，并能大幅度地降低阴性阑尾的切除率和不必要的延期观察。

Diagnostic accuracy of noncontrast-enhanced CT for clinically suspected acute appendicitis;an analysis of 74 cases

Objective To evaluate the diagnostic accuracy of noneontrast-enhanced CT for clinically suspected acute appendicitis. Methods Seventy-four patients with clinically suspected acute appendicitis underwent noncnntrast-enhaneed abdominopelvic （from L1 vertebral body level to upper rim of pubic symphysis） CT scans. The criteria used to diagnose acute appendicitis were an appendieeal diameter of more than 6 mm and inflammatory changes in the periappendieeal fat. The final CT diagnosis was demonstrated by surgery or clinical follow-up. Results Of the 74 patients with clinically suspected acute appendicitis, CT diagnosed 25 true positives, 42 true negatives, 4 false negatives and 3 false positives, resulting in a sensitivity of 86.2 percent, specificity of 93.3 percent, aeeuray of 90.5 percent, positive predictive value of 89.2 percent, and negative predictive value of 91.3 percent. Conclusion Noneontrast-enhanced CT is highly accurate in diagnosing or ruling out acute appendicitis and may substantially decrease the negative appendectomy rate as well as unnecessary delayed observation.