低剂量CT引导下肺穿刺活检的临床应用价值评估

目的 评估低剂量CT引导下经皮肺穿刺活检的临床应用价值。 方法 将2009年1月至2011年12月来本院行肺部占位性病变穿刺活检的200例患者根据就诊顺序依次进行编号后，用SPSS软件产生随机数字后将单数纳为常规剂量组，双数纳入低剂量组，两组均为100例。低剂量组患者行低剂量CT扫描（30 mA，3 mm重建层厚）并穿刺，常规剂量组行常规剂量CT扫描（150 mA，3 mm重建层厚）并穿刺。两组患者经过常规消毒穿刺，取组织样品送病理检查后，分别比较各组在辐射剂量［指标为CT吸收剂量加权指数（CTDIw）、平均剂量长度乘积（DLP）］、图片质量（对图像的肺窗及纵隔窗分别进行盲法判断，分为1～4分，评分＞2分视作图像可接受，适合穿刺活检）、穿刺成功率及病理检查准确率方面的差异有无统计学意义。 结果 在辐射剂量方面，CTDIw：低剂量组为1.48 mGy, 常规剂量组为7.38 mGy；DLP：低剂量组为（11.52±1.72）mGy×cm，常规剂量组为（67.25±4.69）mGy×cm，两组差异有统计学意义（t=40.46，P＜0.05）；在图片质量方面，两组在图像质量可接受性方面均为100.0%（所有患者评分均＞2分）；常规剂量组和低剂量组穿刺成功率分别为98.0%（98/100）和99.0%（99/100），穿刺成功率差异无统计学意义（校正χ²=0.00，P＞0.05）。关于病理检查诊断准确率及误诊率，低剂量组及常规剂量组分别为82.8%（82/99）、13.7%（13/95）和89.8%（88/98）、8.3%（8/96），经过统计学分析两组差异无统计学意义（χ²_{诊断准确率}=2.02，χ²_误诊率=1.39；P值均＞0.05）。 结论 低剂量CT引导下的经皮肺穿刺活检术在大大降低辐射剂量的同时为肺部占位性病变的明确诊断提供了重要的依据，因此具有高度的临床应用价值，值得大力推广。

Clinical value of percutaneous low-dose computed tomography-guided biopsy

Objective The purpose of this study was to evaluate the clinical value of pulmonary biopsy for lung occupying lesions under low-dose computed tomography（CT）-guidance.Methods From January 1 2009 to December 31 2011,200 consecutive patients with pulmonary occupying lesions prepared for lung biopsy were randomly assigned to either standard dose group or low-dose group that containing 100 patients in each group.Of these patients,100 patients underwent percutaneous needle lung biopsy under low-dose CT guidance（30 mA,3 mm reconstruction thickness）,while the other 100 patients underwent standard CT-guided procedure（150 mA,3 mm reconstruction thickness）.Following steps of sterilization,puncture and biopsy,data from two groups were analyzed statistically including such parameters as radiation dose（CTDIw,DLP）,score of image quality of pulmonary and mediastinal window（range from 1 to 4,2 as acceptance）,successful puncture rate and histological result as well.Results The measured CTDIw（weighted CT dose index） was 1.48 mGy in low-dose CT lung biopsy group and 7.38 mGy in standard dose CT group;mean DLP（dose length product） was（11.52±1.72）mGy×cm and（67.25±4.69）mGy×cm,respectively,indicating significant difference between two groups（t=40.46,P0.05）.Howe-ver,acceptance rate in both groups was 100.0% with no significance（all patients＇ score 2）.Also,there was also no statistical difference on successful puncture rate（correction χ2 value=0.00,P0.05） in standard group（98.0%,98/100） compared to low-dose group（99.0%,99/100）.In addition,accurate diagnosis rate and false diagnosis rate in malignancy were 82.8%（82/99）,13.7%（13/95） in low-dose group and 89.8%（88/98）,8.3%（8/96） in standard group,showing no differences（χ2accuracy=2.02,χ2false=1.39,P0.05）.Conclusion Percu-taneous needle lung biopsy under low-dose CT-guidance which minimizes the radiation dose could provide high diagnostic accuracy for lung space occupying lesions,deserving to be applied comprehensively to clinical practice.