| Background and Objective:The disease of thyroid nodule is very common. It is important to early make a diagnosis and give treatment and avoid excessive treatment. The ultrasound is the preferred imaging method of diagnosing the disease of thyroid nodule. By observing the characteristic of each ultrasonogram of the nodules to determine the properties of nodules. This study will assign the features of ultrasonogram of thyroid nodules, the quantitative evaluation method is used to quantitatively analyze the diagnostic value of conventional ultrasound to the benign and malignant diagnosis of thyroid nodule.The elastography is one of the emerging technologies of ultrasound, it evaluates the property of nodules through measuring the hardness of focus of infection. This study introduces the quantitative evaluation method of elastic imaging technology(shear wave elastography) and the semi-quantitative evaluation method of elastic imaging technology(strain rate ratio method) to analyze the diagnostic value of both in differential diagnosis for the properties of thyroid nodule. At the same time, through the combination of conventional ultrasound and elastography technology to discusses the differential diagnosis value of double modal diagnostic method to benign and malignant diagnosis of thyroid nodule. And on the basis of aboveresearch to analyze the effect of nodular calcification to the shear wave elastography.Methods:A total of 108 focal lesions were identified in the study group.Firstly, using TOSHIBA Aplio XG(with a 8~14 MHz linear probe) color Doppler ultrasound diagnostic apparatus, color duppler ultrasound characteristics of nodules were observed. The ultrasound was performed to assess the echogenicity and echostructure of the lesions, their margin, the halo sign, the height/width ratio(H/W ratio),the presence of calcifications and the vascularization pattern. Secondly, the elastography characteristics of SR imaging was analyzed. Then using Aixplorer( Super Sonic, Aix-en-Provence),with a 4-15 MHz linear probe, the characteristics of SWE imaging were retrospectively analyzed. This was followed by an analysis of maximum and mean Young`s(E)modulus values for thyroid nodules. Compared with Histopathological result as the gold standard, sensitivity(SEN), specificity(SPE) and the accuracy(ACC) were calculated for color Doppler ultrasound and two kinds of ultrasound elasticity imaging alone,ingcluding Shear wave elastography(SWE) and Strain Ratio(SR), and the combination of color Doppler ultrasound with two kinds of ultrasound elastography imaging in differential of benign and malignant thyroid nodules. Then another 108 patients were examined by using shear wave elastography(SWE) to investigate the impact of calcification on differential diagnosis of thyroid nodule.Results:1.There were 40 benign nodules and 68 malignant nodules.2.108 thyroid nodules underwent conventional ultrasound examination,confirmed by the postoperative pathological results, 40 nodules are benign and 68 nodules are malignant. Drawing ROC curve for conventional ultrasound, the area under the curve was 0.798.Considering the score 3 as the best diagnostic standard,the sensitivity is70.6%,the specificity is 82.5%, and the accuracy is 75.0%.3.108 thyroid nodules underwent SWE examination, confirmed by thepostoperative pathological results, 40 nodules are benign and 68 nodules are malignant, the average Young`s modulus values of the benign group was 28.5 ±14.39 Kpa, and the average Young`s nodulus values of the malignant group was54.93 ± 15.48 Kpa. There was significant difference between them. According to1-specifility as the abscissa and sensitivity as ordinate, drawing ROC curve for conventional ultrasound, the area under the curve was 0.810.Considering the Young`s modulus value of 33.03 Kpa as the best diagnostic standard, the sensitivity is75.0%,the specificity is 85.0%, and the accuracy is 78.7%. The greater the Young`s modulus value is,the greater the likelihood of malignant nodules.4.Position the reference ROI in normal parenchyma in the same depth as the examined nodule. 108 thyroid nodules underwent SR examination, confirmed by the postoperative pathological results, 40 nodules are benign and 68 nodules are malignant, the average value of the benign group was 2.32±2.15,and the average value of the malignant group was 8.96±4.57. There was significant difference between them. According to 1-specifility as the abscissa and sensitivity as ordinate,drawing ROC curve for conventional ultrasound, the area under the curve was0.759.Considering the value of 3.35 as the best diagnostic standard, the sensitivity is73.5%,the specificity is77.5%, and the accuracy is 75.0%. The greater the value is,the greater the likelihood of malignant nodules.5.The combination of conventional ultrasound with SWE has higher sensitivity,specificity and accuracy. Its sensitivity is 85.3%, and the specificity is 87.5%, the accuracy is 86.1%. Drawing ROC curve for conventional ultrasound with SWE, the area under the curve was 0.872.When conventional ultrasound combined with SR,the sensitivity is 76.5%, and the specificity is 82.5%, the accuracy is 78.7%.Drawing ROC curve for conventional ultrasound with SR, the area under the curve was 0.817.6.The average Young`s modulus values of the benign group which without calification was 29.37±16.77 Kpa,and the average Young`s nodulus values of the malignant group which without calification was 46.92 ± 15.41 Kpa. There was significant difference between them. According to 1-specifility as the abscissa and sensitivity as ordinate, drawing ROC curve for conventional ultrasound, the areaunder the curve was 0.825. Considering the Young`s modulus value of 30.43 Kpa as the best diagnostic standard, the sensitivity is 93.2%,the specificity is 81.2%, and the accuracy is 84.8%. The average Young`s modulus values of the benign group which with calification was 48.2±8.74 Kpa,and the average Young`s nodulus values of the malignant group which without calification was 61.2 ± 10.49 Kpa. There was no significant difference between them. According to 1-specifility as the abscissa and sensitivity as ordinate, drawing ROC curve for conventional ultrasound, the area under the curve was 0.551.Conclusion:1.Conventional ultrasound examination had important diagnostic value in thyroid nodules.2.Various ultrasound elasticity imaging methods are helpful to antidiastole benign and malignant thyroid nodules. If color Doppler ultrasound combined with elastography(SWE,SR), the diagnostic consistency with pathological result is marked improved compared with color Doppler ultrasound or elasticity imaging alone.3.In no calcification group, SWE is more meaningful in the differential diagnosis of benign and malignant thyroid nodules. |
PDF Full Text Request