Manjiri K. Dighe MD, Presenter: Nothing to Disclose

Si Luo MEng, Abstract Co-Author: Nothing to Disclose

C. Diana Jordan MD, Abstract Co-Author: Nothing to Disclose

Yongmin Kim PhD, Abstract Co-Author: Nothing to Disclose

To evaluate utility of thyroid elastography using in-vivo compression in differential diagnosis of small <1 cm thyroid nodules.

A study was conducted, after HSD approval, at our institution to perform elastography in all thyroid FNA patients. Elastography data were acquired with in-vivo compression using the Hitachi EUB-5500 machine prior to the FNA. Elastography images were generated off-line. A metric, called elasticity contrast index (ECI), was computed to quantify the elasticity contrast between the nodule and its surrounding normal tissue. A total of 37 nodules smaller than 1 cm in the transverse dimension were included. One patient had 2 nodules that were smaller than 1 cm. Retrospective analysis was performed on these 37 small nodules and elastography results were compared to FNA and/or histopathology results.

For all cases, thyroid nodule(s) could be distinguished from the surroundings in elasticity images. One nodule was excluded due to inadequate FNA results. A total of 8 malignant lesions were seen in the study population with the rest (28) being benign. Using a cut-off of 3.6, ECI was able to diagnose all malignant lesions. 11 benign lesions had an ECI = or > 3.6 while 17 benign lesions had ECI < 3.6. The ECI cut-off of 3.6 yielded a sensitivity of 100% and specificity of 60.71% (p = 0.0002).

Our study indicates that thyroid elastography using in-vivo compression is effective in differential diagnosis of small <1 cm thyroid nodules. In addition, using thyroid elastography with internal compression, 47% of FNA on small < 1cm nodules could be avoided leading to more efficient utilization of health care resources.

Thyroid elastography using in-vivo compression shows promise in diagnosing small < 1cm malignant lesions non-invasively or avoiding biopsy in benign lesions.

Dighe, M, Luo, S, Jordan, C, Kim, Y, Efficacy of Thyroid Elastography in Differential Diagnosis of Small <1 cm Thyroid Nodules.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9004202.html