Impact of manual operations of Ultrasound Elastography on differentiating between benign and malignant breast masses

• Main Authors: Chia-Ying Hsieh, 謝佳穎
• Other Authors: E-Fong Kao
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/6z5e2e

碩士 === 高雄醫學大學 === 醫學影像暨放射科學系碩士班 === 103 === The breast ultrasound gray-scale image is evaluated according to the shape, margin, echo pattern, posterior acoustic features and calcification of the lesion, so as to distinguish whether the lesion is benign or malignant. Its sensitivity of detecting breast tumor is high, but the specificity is much lower, which causes the patients to have many unnecessary biopsies. As the benign or malignant breast lesion is highly correlated with the hardness of the tissues, the breast elastography has emerged in recent years to assist in improving the specificity of the breast tumor detection. However, the results of the Radiological diagnosis Department in a regional teaching hospital in southern Taiwan, which introduced the breast ultrasound elastography in 2013, show that the diagnostic effects were not as good as expected. The inspection of the breast ultrasound elastography depends heavily on the operating methods of the users, so this study conducts a series of examinations on the correlation between different operating methods of the breast ultrasound elastography and the discrimination of benign and malignant breast masses. The study comprises two parts: the first part chiefly discusses the correlation between different ROIs (region of interest) of manually selected lesions and the differential diagnosis of benign or malignant lesions and the second part studies the impact of the pressurized field of view (FOV) on the differential diagnosis of benign or malignant lesions. The first part collected 35 lesions from 32 patients, while the second part collected 63 lesions from 59 patients. All lesions include both the elastography and biopsies, and the data analysis used the results of biopsies as the standard to evaluate the efficiency of the elastography in discriminating benign or malignant masses. And the discrimination is represented by the area (Az) under the receiver operating characteristic (ROC) curve. The first part of the study compared the manual methods of selecting ROIs (region of interest) and the results show that there were no significant differences (p =1) between the hardest part and the greatest area of the selected lesions. The second part of the study compared the impact of the pressurized FOV on the discrimination of benign or malignant lesions and the results show that Az was 0.651 when there was no specifically restricted pressurized FOV and Az was 0.855 when the restricted pressurized FOV didn’t include the lung. When the pressurized FOV didn’t include the lung, the discrimination of the elastography on benign or malignant tumors can be improved effectively. The study investigates the influence of different operating methods of breast ultrasound elastography on the discrimination of benign or malignant breast masses. The results show that there were no significant differences between the hardest part and the greatest area of the selected lesions and the pressurized FOV excluding the lung would improve the discrimination of the elastography on benign or malignant tumors. The study results help to decrease the error of manual operation, provide the standards for clinical ultrasound operating personnel to analyze the elastography of the lesions and further improve the diagnostic accuracy of breast ultrasound elastography.