Abstract:

Objective To assess the value of reduced field-of-view intravoxel incoherent motion（IVIM） diffusion-weighted imaging for differentiating benign from malignant thyroid nodules. Methods The IVIM technique was used to visualize 75 thyroid nodules in 48 patients and determine benign or malignant status. These findings were compared with pathology results. Standard，Slow and Fast ADC values as well as f values were compared for the two groups. Receiver operating characteristic（ROC） curves were generated to determine diagnostic thresholds. Results  Benign nodules showed significantly higher values than malignant nodules for Standard ADC（1.90±0.45 vs 1.15±0.21×10^-3 mm²/s） and for Slow ADC（1.63±0.06 vs 0.96±0.23×10^-3 mm²/s） and marginally（non-significantly） lower values for Fast ADC（153.44±104.58 vs 172.25±106.97×10^-3 mm²/s） and for f value（20.95±9.04 vs 22.94±8.60%）. The area under the ROC curve was for 0.961 for standard ADC，which showed a sensitivity of 89.47% and specificity of 100%. The corresponding area for Slow ADC was 0.936，sensitivity was 89.47% and specificity was 96.43%. Conclusion Reduced field-of-view IVIM diffusion-weighted imaging has diagnostic potential for differentiating benign and malignant thyroid nodules.

Key words: Thyroid neoplasms, Reduced field-of-view, Diffusion-weighted imaging, Intravoxel incoherent motion, Differentiation diagnosis