Advanced

AJNR - American Journal of Neuroradiology

Published ahead of print on November 26, 2007
doi: 10.3174/ajnr.A0849

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: ajnr.A0849v1 29/3/563    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Razek, A.A.K. A. Articles by Nada, N. Search for Related Content PubMed PubMed Citation Articles by Razek, A.A.K. A. Articles by Nada, N.

American Journal of Neuroradiology 29:563-568, March 2008
© 2008 American Society of Neuroradiology

HEAD & NECK

Role of Apparent Diffusion Coefficient Values in Differentiation Between Malignant and Benign Solitary Thyroid Nodules

A.A.K. Abdel Razek^a, A.G. Sadek^a, O.R. Kombar^a, T.E. Elmahdy^b and N. Nada^c

^a Department of Diagnostic Radiology, Mansoura Faculty of Medicine, Mansoura, Egypt
^b Department of Endocrine Surgery, Mansoura Faculty of Medicine, Mansoura, Egypt
^c Department of Pathology, Mansoura Faculty of Medicine, Mansoura, Egypt

Please address correspondence to Ahmed Abdel Khalek Abdel Razek, MD, Diagnostic Radiology Department, Mansoura Faculty of Medicine, 62 El Nokrasi St, Mansoura, Egypt; e-mail: arazek{at}mans.eun.eg

BACKGROUND AND PURPOSE: Accurate imaging characterization of a solitary thyroid nodule has been clearly problematic. The purpose of this study was to evaluate the role of the apparent diffusion coefficient (ADC) values in the differentiation between malignant and benign solitary thyroid nodules.

MATERIALS AND METHODS: A prospective study was conducted in 67 consecutive patients with solitary thyroid nodules who underwent diffusion MR imaging of the thyroid gland. Diffusion-weighted MR images were acquired with b factors of 0, 250, and 500 s/mm² by using single-shot echo-planar imaging. ADC maps were reconstructed. The ADC values of the solitary thyroid nodules were calculated and correlated with the results of histopathologic examination. Statistical analysis was performed.

RESULTS: The mean ADC value of malignant solitary thyroid nodules was 0.73 ± 0.19 x 10^–3 mm²/s and of benign nodules was 1.8 ± 0.27 x 10^–3 mm²/s. The mean ADC values of malignant nodules were significantly lower than those of benign ones (P = .0001). There were no significant differences between the mean ADC values of various malignant thyroid nodules, but there were significant differences between the subtypes of benign thyroid nodules (P = .0001). An ADC value of 0.98 x 10^–3 mm²/s was proved as a cutoff value differentiating between benign and malignant nodules, with 97.5%, 91.7%, and 98.9% sensitivity, specificity, and accuracy, respectively.

CONCLUSION: The ADC value is a new promising noninvasive imaging approach used for differentiating malignant from benign solitary thyroid nodules.