Diffusion-weight magnetic resonance imaging in the diagnosis of tyroid nodules

Purpose:In order to determine the treatment plan of tyroid nodules, the differentiation of benign-malignant should be made. This differentian cannot be made with the rutin sequences of MRI which is a non invasive inspection method.In our retrospective study, the aim is to compare the histopathological results and DWI in patients who went under rutin neck MRI.Material and Methods:In our examination nodules which were collected from 46 patients, who went under rutin neck MRI with the GE Signa HDx 1.5 T device between the dates 06.01.2010 and 05.06.2011 were evaluated. In the neck MRI, sagital T2, axial T2, axial T1, diffusion b 500 and b 800 sequences were used. By forming ADC maps, ADC measurements were obtained by placing ROI over from the parts of the nodules which were not cystic or hemorrhagicFindings:37 out of 46 nodules were considered as benign whereas 9 were malignant. Mean ADC value for benign nodules was 1.9x10-3 for b 500 factor and 1.3x10-3 for b 800 factor; mean ADC value of malignant nodules was calculated as 1.6x10-3 for b 500 factor and 1.0x10-3 for b 800 factor respectively.In the differentiation of bening and malignant nodules when the cut-off value for ADC 1,1x10-3; the differentiation sensitivity for b 500 factor ADC values was found to be %83,3 and the specifity was %90,0, whereas the sensitivity was %71,4 and the specifity was %89,7 for b 800 factor ADC nodule.Result:Diffusion weighted imaging in tyroid noduls in a method which is considered to be available in short term, needless of contrast material and hav additional benefits to convantional sequences and to diagnosis.Keywords:ADC, Diffusion-weighted magnetic resonance imaging,Tyroid nodüle.