Role of Ultrasound and Magnetic Resonance Imaging in Assessment of Thyroid Nodules

Background:Thyroid nodules are very commonly observed on thyroid imaging. A minority of thyroid nodules is malignant; even so, many invasive diagnostic procedures are performed to discriminate between benign and malignant nodules.The aim of this work was to determine the great role of Ultrasonography and Magnetic Resonance Imaging in assessment of thyroid nodules and to reduce cost-effectiveness by decreasing number of unnecessary fine needle aspiration cytology (FNAC).Methods: All patients in the study were subjected to full history taking and clinical examination. Gray-scale Ultrasound and color Doppler examination were done to all patients. The nodules were classified into TIRADS categories. According to TIRADS categories, they were classified into group (A) and group (B).Results:12patients with 16 nodules were subjected to MRI examination. 11 nodules showed free diffusion with higher ADC values and 5 nodules showed restricted diffusion with lower ADC values. On comparison with histopathological examination, most of the nodules with restricted diffusion and lower ADC values were proven to be malignant. So DWI-MRI has high sensitivity (91.7%) and specificity (100%) in differentiating benign and malignant thyroid nodules.Conclusion: DW-MR imaging has a useful role in the evaluation of the thyroid nodules and post thyroidectomy recurrent nodules providing a good determining tool by the measurement of the ADC value. Contrast enhancement could provide complementary data for differentiation.