基于CT扫描模型的胸腔气道测量方法研究  

Research on Measurement Method of Intrathoracic Airways Based on CT Scanning Model

作　　者：谢湘[1,2] 邓振生[1,2] 刘驰[2] 

机构地区：[1]中南大学有色金属成矿预测教育部重点实验室,长沙410083 [2]中南大学地球科学与信息物理学院,长沙410083

出　　处：《中国生物医学工程学报》2012年第3期406-410,共5页Chinese Journal of Biomedical Engineering

摘　　要：基于二维CT图像的胸腔气道高精度测量对肺部疾病的诊断具有重要意义。但是由于CT图像在成像过程中不可避免的模糊,使得气道内外壁无明显边界,导致确定内外壁位置的难度加大,测量误差大。本研究分析了CT扫描数学模型,然后采用优化技术合理设置参数调整模型,并与真实气道灰度轮廓进行最大程度匹配,以实现一定精度范围内气道的精确测量。模型对比实验表明,本方法与目前流行的半高宽法相比具有较高的测量精度和稳定性。将该方法应用于19例慢性阻塞性肺炎(COPD)患者实际胸部CT气道测量实验,测量正确率为96.2%,能较好地满足临床测量要求。Airway geometry measurement of high-precision based on 2D CT images is significant for the diagnosis of lung disease.However,airway wall borders are not able to be well-defined due to inevitably introduced blurring in the CT images,which is likely to raise difficulties of determining inner or outer airway wall locations and result in measurement errors.In this work,firstly,the mathematical model of CT scanning was analyzed;optimized technique was adopted to reasonably set the parameter adjusting model.The parameter model was then matched with the contours of the true gray levels of the airways to the greatest degree to obtain airway geometry measurement within a certain range of accuracy.Comparative experiments of the models showed that results obtained from the established method had higher accuracy and greater stability compared with that of commonly used FWHM.The method was applied to airway measurements of 19 cases of COPD patients,results showed the method had an accuracy of 96.2%,which can basically meet the requirements of clinical measurement.

关 键 词：慢性阻塞性肺炎 高分辨率CT 气道测量 半高全宽法 点扩散函数 

分 类 号：R318[医药卫生—生物医学工程]