ABSTRACT
Objective To analyse the influencing factors diagnosed by the virtual touch tissue quantification (VTQ) technology on the hardness of papillary thyroid carcinoma (PTC).Methods From May 2011 to March 2014,a total of 266 PTCs in 266 patients confirmed by pathology were enrolled in Shanghai Tenth People's Hospital.The shear wave velocity (SWV) values of PTCs were measured by VTQ.PTCs were divided into 2 groups including SWV ≥ 2.87 rn/s and SWV ＜ 2.87 rn/s.The x2 test was used to compare the basic clinical data,ultrasound features and immunohistochemical results between 2 groups.The influencing factors of SWV values of PTCs were analyzed by forward stepwise Logistic regression analysis.Results Of the 266 PTCs,183 were SWV ≥ 2.87 m/s and 83 were SWV ＜ 2.87 m/s.The x2 test showed that the ultrasound features of PTCs such as single or multiple,with or without central lymph node metastasis,location,size,shape,with or without posterior acoustic attenuation,with or without calcification,with or without capsule invasion,whether close to the trachea between the 2 groups were significant different (x2=4.233,4.740,9.910,4.988,4.416,4.737,7.154,8.559,all P ＜ 0.05 or 0.01).Logistic regression analysis demonstrated that nodules were single or multiple,location,with or without posterior acoustic attenuation,with or without calcification,whether close to the trachea were influencing factors of SWV value of PTCs.The regression equation was defined as Y=-2.507 + 0.670X1 (nodules were single or multiple) + 0.800X3 (location of nodules) + 0.851X6 (with or without posterior acoustic attenuation) + 0.628X7 (with or without calcification) + 1.106X9 (whether close to the trachea).Conclusions Multiple nodules,central lymph node metastasis,located isthmus,nodules size ＞ 10 mm,irregular shape,posterior acoustic attenuation,calcification,capsule invasion,close to the trachea were correlated with the diagnosis of PTC by VTQ technology.The more characteristics of nodules appeared,such as multiple nodules,located isthmus,posterior acoustic attenuation,calcification,close to the trachea,the harder PTCs were.
ABSTRACT
Objective To evaluate diagnostic value of the novel virtual touch tissue imaging quantification (VTIQ) technique of acoustic radiation force impulse (ARFI) shear wave elastography in the differential diagnosis between benign and malignant thyroid lesions. Methods From June to July 2014, the imaging data of 82 thyroid lesions in 75 patients proven by fine needle aspiration cytology (FNAC) biopsy on conventional ultrasound and VTIQ were retrospectively analyzed. The thyroid nodules were examined by conventional ultrasound firstly and then the lesions were classified by thyroid imaging report and data system (TI-RADS). The maximum, minimum, median and average of shear wave velocity (SWV) values were obtained from multiple SWV measurement under the VTIQ speed mode. The region of interest (ROI) was determined according to the VTIQ quality mode after the patients holding the breath. According to the FNAC cytology results, ROC curve were plotted to determine the most accurate SWV value and the cut-off value for differential diagnosis. Results According to the FNAC results, grading≥5 level was set as the positive results and FNAC<5 level as the negative results. There were 28 positive nodules and 54 negative nodules in 82 thyroid nodules. The positive rates of TI-RADS classification were consistent with the theoretical results. The SWVmax, SWVmin, SWVmedian, and SWVmean on VTIQ of negative and positive thyroid nodules were (3.2±0.6), (2.2±0.4), (2.7±0.4), (2.6±0.4) m/s, and (4.6±1.7), (3.1±0.8), (3.5±1.0), (3.6±1.1) m/s. There were significant differences between positive and negative thyroid nodules in SWVmax, SWVmin, SWVmedian, and SWVmean on VTIQ (t=3.53, 3.68, 3.32, 3.81, all P<0.01). Based on the area under curve of ROC, the SWVmean value in the nodule was the best value in comparison with other SWV values. The cut-off value of VTIQ mean was 2.9 m/s. According to ROC curve analysis, the sensitivity, specificity and Youden index for VTIQ were 70.6%, 88.5%, 0.59, respectively. Conclusion The study proved that VTIQ elastography technique plays an important role in differential diagnosis of thyroid nodules and the VTIQ SWVmean is the best parameter for differential diagnosis.