الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Ultrasound is considered the imaging modality of choice to examine the thyroid gland. The Committee of the American College of Radiology (ACR) published a white paper about Thyroid Imaging Reporting and Data System (TIRADS) which is considered a scoring system for classifying thyroid nodules upon their ultrasonographic features. characterization of thyroid nodules not only depends on single sonographic finding, but it depends on all sonographic feature regarding its composition, echogenicity, margin, orientation and presence or absence of echogenic foci; to identify the high risk of malignancy. Recently, magnetic resonance imaging (MRI) has gained importance in the detecting and classifying of thyroid nodules through the application of diffusion-weighted MRI (DWI) which is an important diagnostic tool for assessing in vivo tumor characterization. Structural changes of malignancies or benign thyroid tissue can be evaluated with the apparent diffusion coefficient (ADC), which is an objective parameter of the tissue-specific diffusion capacity of a biologic tissue. Ultrasound guided fine needle aspiration (FNA) cytology plays a master role in detecting the histopathological type of thyroid nodules. However, it is relatively expensive. So, TIRADS was designed to identify nodules with high risk of malignancy to limit the unneeded FNAs. The aim of this study was to evaluate the role of ultrasound and diffusion weighted magnetic resonance imaging in differentiation of benign & malignant thyroid nodules.
This study was conducted on 30 patients with thyroid nodules with age range from 18 to 75 years and mean age was 44.57 ± 14.84 years. Twenty-eight patients were females (93.3 %) and two were males (6.7 %). They were subjected to neck ultrasound examination, MR imaging with DWI and correlation to histopathological results of thyroidectomy specimen & fine needle aspiration for all cases. There were 19 benign nodules and 11 malignant nodules.