Manjiri K. Dighe MD, Presenter: Research Grant, General Electric Company

Jeff Thiel, Abstract Co-Author: Nothing to Disclose

Daniel S. Hippe MS, Abstract Co-Author: Research Grant, Koninklijke Philips NV Research Grant, General Electric Company

To assess the difference in measurement of stiffness values within a thyroid nodule using Shear-Wave elastography with various regions of interest methods.

After IRB approval, elastograms were obtained by Shear-wave elastography from 77 individuals, with a total of 88 thyroid nodules. Elastography data was acquired without any external compression using the Supersonics Aixplorer machine. 1 reader blinded to the cytopathology or the final histopathology results was asked to draw regions of interest (ROIs) in the nodule. These included a 3mm ROI on the stiffest part of the nodule as seen on the elastogram image (3mm), ROI covering the whole nodule (WN), ROI covering the whole nodule and the margin of the nodule (WNM) and a circular ROI over the edge of the nodule (EN). The stiffness values were recorded for each of these measurements. Each nodule had multiple elastography images taken and an average value of the measurements (mean and max) for each nodule was calculated for various methods of measurement (3mm, WN, WNM and EN). Results were compared between the FNA + surgery and only surgery group as shown in the table

In the FNA + surgery group, the area under the curves (AUC) were similar for the various methods of measurement for both the mean and max kPa values. For the surgery only group, whole nodule ROI and whole nodule and the margin of the nodule ROI had marginally better AUCs compared to the 3mm ROI and the edge ROI.

Our study indicates that measuring the stiffness in the whole nodule would be better than measuring the stiffest area since the variability in measurement would be less. This is likely because the reproducibility of measuring the ROI in the whole nodule would be better than picking out the stiffest area in the nodule.

Decreasing the variability in measuring the stiffness within a nodule in thyroid elastography is important since the results would be much more accurate and more reproducible.

Dighe, M, Thiel, J, Hippe, D, Methods of Measurement of Stiffness Value within a Thyroid Nodule on Shearwave Elastography.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012417.html