乳腺电阻抗扫描成像数值分析

Numerical analysis of electrical impedance scanning imaging of breast

针对已有的电阻抗扫描成像分析模型与临床实际情况存在较大差异的问题,结合女性乳房结构、中国女性乳房实际大小、电参数及检测探头结构,构造了一个更加接近于实际情形的电阻抗扫描成像模型.采用有限元方法求解模型的静态电场方程并结合方差分析(Yates方法)对电阻抗扫描成像的相关参数进行统计分析.结果表明,当乳房中存在癌灶时,由于癌灶组织与周围正常组织在电参数上存在差异,乳房表面电流会存在相应的扰动.电流扰动程度受乳房大小、癌灶深度、大小以及周围组织电导参数及其交互因素的影响.如能通过测量夹具控制乳房大小,减少癌灶深度,可进一步提高电阻抗扫描成像的乳腺癌检测性能.

The existing models for analyzing electrical impedance scanning imaging （EISI） may pro- duce results significantly different from real clinic findings. According to women＇s breast structure, Chinese women＇s breast size, electric parameters of breast, and the structure of EISI probe, an im- proved EISI model is presented. Statistic analysis of EISI parameters is presented by the finite ele- ment method （ solving quasi-static equation of the imaging model） and the Yates method （ analysis of variance）. Results indicate that the measured current at breast surface can display corresponding disturbance when there is cancerous lesion within breast due to different conductance in breast cancer- ous tissue and surrounding normal tissue. Degree of current disturbance is related with the breast size, the depth and radius of cancerous lesion, the conductance of surrounding tissue of cancerous lesion, and the interaction between above parameters. If the breast size and the depth of cancerous lesion can be decreased by measurement jig, the detection performance of breast cancer can be improved.