A Comparative Analysis of DWI and Ultrasound in Thyroid Nodules

Abstract Background Diffusion weighted imaging and ultrasound are commonly used methods to examine thyroid nodules, but their comparative value is rarely studied. To evaluate the value of diffusion weighted imaging and ultrasound in differentiing benign and malignant thyroid nodules Methods A total of 100 patients with 137 nodules were enrolled. who underwent both diffusion weighted imaging and ultrasound before operation. T1 and T2 signal intensity ratio (SIR) of each thyroid nodule was calculated by measuring the mean signal intensity divided by that of paraspinal muscle. The value of ADC,signal intensity ratio (SIR) of benign and malignant thyroid nodules were analyzed by two independent sample t test. The sensitivity, specificity and accuracy of DWI and ultrasound were compared and analyzed by chi-square test. Results There was no significant difference in signal intensity ratio between benign and malignant thyroid nodules. The ADC value had significant difference. When the threshold value was 1.12 ×10-3 mm2/s, the maximum area under the curve was 0.944,The sensitivity, specificity and accuracy were 84.9%, 92.2% and 87.6% respectively. The sensitivity and specificity of ultrasound diagnosis were 90.1%, 80.4% and 86.9% respectively. Conclusion Ultrasound has high sensitivity in differentiating benign and malignant thyroid nodules, and ADC value has high specificity in differentiating thyroid nodules, but there is no statistical difference in sensitivity and specificity between the two. DWI and Ultrasound have their own advantages in differentiating benign and malignant thyroid nodules.