| ObjectiveTo investigate the differential diagnosis value of magnetic resonance imaging（MRI）between Graves disease with hyperthyroidism and early Hashimoto’s thyroiditis.Materials and methodsThe participants were chosen consecutively at the endocrine outpatient of Shandong Provincial Hospital between December 2015 and January 2017.A total of 15 patients with Graves disease were compared with 12 patients with early Hashimoto’s thyroiditis and ten healthy control subjects.The participants underwent axial DWI scan of different b values（the b value were 150,300,550 separately）and axial FS-T2WI scan.The ADCvalues of DWI and the ratio of signal intensity between thyroid gland and paravertebral muscle in fat suppression T2 weighted imaging（FS-T2WI）were measured.The ADC values and the ratio of signal intensity was acquired by measuring average value of three times.The statistical analysis of data was done using SPSS program（Statistical Package of Social Science）version 19.0.To compare between the three groups,one-way analysis of variance test was used.A P value of≤0.05 was considered to be statistically significant.The receiver operating characteristic curve was drawn to detect threshold value for ADC value used to the patients with early Hashimoto’s thyroiditis and then calculated the area under ROC curve,sensibility and specificity.Results（1）The ADC value decreased with the increase of b value in the same group;（2）There was significant difference in ADC value between different groups with the same b value（P<0.05）;（3）When b value is 550,the ADC value showed more difference significantly than the ADC values of the other two b values.（4）There are difference signisifant in the ratio of signal intensity between thyroid gland and paravertebral muscle in fat suppression T2 weighted imaging during different groupes.However,the statistically difference is not significant between the patients with Graves disease and hyperthyroidism and the patients with early Hashimoto’s thyroiditis.（5）In the group of early Hashimoto thyroiditis,when b=150,ADC=1.88×10-3mm2/s,the area under ROC curve,sensitivity and specificity were 81.8%,100%,81.8%,respecti vely;when b=300,ADC=1.60×10-3mm2/s,the area under ROC curve,sensitivity and specificity respectively.81.8%,100%,81.8%;when b=550,ADC=1.30×10-3mm2/s,the area under ROC curve,sensitivity and specificity were 90.9%,100%,90.9%respectively.Conclusions（1）The ADC values of different b values and the ratio of signal intensity alterations were specific in the patients with Graves disease wih hyperthyroidism and the patients with early Hashimoto’s thyroiditis（2）The sensitivity and specificity is significantive in the quantitative analysis of DWI for the patients with early Hashimoto’s thyroiditis.Especially,when b=500,ADC<1.66×10-3mm2/s,The application valuemore is more prominent;（3）There is meaningless for the ratio of signal intensity in the identification between he patients with Graves disease with hyperthyroidism and the patients with early Hashimoto’s thyroiditis. |
