Comparative Study Of Quantitative MRI And Conventional Ultrasound In The Diagnosis Of Thyroid Nodules

Objective:To investigate the 3.0T magneticresonance imaging?Magnetic resonanceimaging,MRI?and conventional ultrasound imaging?Ultrasound imaging,US?featuresin the inspection in benign and malignant thyroid nodules,analysis of the diagnosis value and clinical appli-cation of MRI?quantitative examination and ultrasonography in diagnosing benign and malignnant thyroid nodules.Materials and Methods:This study included 30 cases of thyroid nodules confirmed by operation or biopsy,which were given diagnosis and treatment of thyroid and breast surgery Shandong provin-cial hospitalfrom 2016/01²017/01,all patients with a total of 40 nodules,including 19benign lesions?maximum diameter range,0.5².8mm;the average diameter[±SD],1.44±0.63mm?and 21malignantlesions?maximum diameter range,0.4-2.5mm;the average diameter[±SD],1.25±0.58mm?,and obtain informed consent from the patient.All patients underwent routine neck scan before treatment using Toshiba-Aplio500 ultrasound diagnostic apparatus,the conventional MRI axial T1WI?axial FS-T2WI and magnetic resonance diffusion weighted imaging?magnetic resonance diffusion weighted imaging,DWI-MRI:b=0?300 s/mm ²?were performed before clinical operation and biopsy.In addition,10 volunteers after informed consent as the normalcontrol group.The signal intensity ratios of lesions in FS-T2WI and TIWI were calculated respectively?Signal intensity ratio,than SIR?,that is to say,the ratio of the average signal intensity of the lesions on FS-T2WI or T1WI and the signal intensity of normal paraspinal muscle tissue at the same level;The threshold value of apparent diffusion coefficient?apparent diffusion coefficient,ADC table?of benign and malignant lesions was calculated by SPSS 20statistical software.The ultrasonographic features of thyroid lesions such as morphology,calcification,margin,echo uniformity,blood flow distribution,lymph node metastasis and distant metastasis were analyzed by a professional physician,The diagnostic results of the patients in routine ultrasound examination were obtained.The T1WI and T2WI signal intensity ratio?SIR?,the image characteristics of benign and malignant lesions of the ADC value and different nodules in MRI were analyzed,determine the best criteria for the diagnosis of benign and malignant nodules in the diagnosis of magnetic resonance.The ROC curves of MRI and US were drawn by SPSS 20 statistical software,and the results of MRI diagnosis and conventional ultrasound were compared.The value of magnetic resonance imaging and conventional ultrasonography in differential diagnosis of benign and malignant thyroid lesions was analyzed.Result:In the experiment,the p value of the T test of the age and the diameter in the benign and malignant lesions was greater than 0.05,In other words,there was no significant difference in the age of onset and the size of benign and malignant nodules.Conventional magnetic resonance imaging showed good anatomical structure of thyroid lesions.The mean SIR value±standard deviation was 0.90±0.11,and the 95%confidence interval was 0.86⁰.95 in the T1WI of malignant nodules;The mean SIR value of benign nodules±standard deviation were 0.92±0.10,95%confidence interval is 0.88⁰.97.P>0.05,the difference was not statistically significant.The mean SIR value±standard deviation was 1.77±0.54,and the 95%confidence interval was 1.58².03 in the FS-T2WI of malignant nodules;The mean SIR value of benign nodules±standard deviation were 3.63±1.17,95%confidence interval is 3.09⁴.17.P<0.05,that is to say,the SIR of benign nodules was significantly higher than that of malignant nodules.The best threshold value is 2.67,the sensitivity,specificity and coin-cidence rate were 95.2%,89.5%and 92.5%,respectively.The mean ADC value of malignant nodules±standard deviation was 1.67±0.32×10^-3mm2/s,and the 95%confidence interval was 1.54¹.83 in the diagnosis of benign and malignant thyroid nodules;The mean ADC value of benign nodules±standard deviation were 2.50±0.28mm2/s,95%confidence interval is 2.37².63mm2/s.P<0.05,the ADC value of benign nodules was significantly higher than that of malignant nodules.The best threshold value is 2.155×10^-3mm2/s,thesensitivity,specificityand coincidence rate were95.2%,89.5%,and 92.5%,respectively.The sensitivity,specificity and coincidence rate were 95.2%,94.7%and 95%in the combined diagnosis of ADC?b=300?and FS-T2WISIR.15 benign lesions were diagnosed by conventional ultrasound,and the other two were malignant in 25 cases.The sensitivity,specificity and coincidence rate were 90.5%,68.4%and 80%,respectively.The sensitivity of ultrasound in the diagnosis is good,and the coincidence rate is high,It is able to identify micro nodule.The AUC values of combined diagnostic,conventional ultrasound,FS-T2WISIR and ADC values?b=300?were 0.950,0.794,0.890,and 0.945,respectively,by ROC curve analysis.The AUC value of quantitative MRI was higher than that of conventional ultrasound,and combined diagnostic is the highest,its AUC value>0.9,It shows that it has high accuracy.and the AUC value of ultrasound showed a certain accuracy between0.7⁰.9.Conclusions:The detection rate of thyroid lesions by conventional ultrasound is high,and the details are clear,it is important to screen the lesions;MRI can display the anatomic structure and location of the lesion,the introduction of quantitative diagnosis makes it possible to differentiate the benign and malignant nodules accurately.The diagnosis effect is excellent,and the clinical application prospect is broad.MRI and ultrasound have some advantages in the diagnosis of benign and malignant thyroid nodules.Quantitative MRI?T2WI signal intensity ratio,ADC value?has a more obvious advantage in the qualitative diagnosis of thyroid nodules.