Acoustic radiation force impulse imaging for evaluation of the thyroid gland.

Objectives: To study acoustic radiation force impulse (ARFI) imaging as a new quantitative and noninvasive tool for evaluating thyroid nodules and to compare ARFI imaging with other tools for studying thyroid nodules: sonography, real-time elastography, and fine-needle aspiration biopsy.

Methods: We conducted a prospective study from June 2011 to June 2012, which analyzed 157 thyroid nodules (129 benign and 28 malignant) using the ARFI technique and a 9-MHz probe. Shear wave velocities (SWVs) were obtained while the patients held their breath to avoid respiratory movement artifacts.

Interobserver agreement for thyroid elastography: value of the quality factor.

Objectives: The purpose of our study was to investigate interobserver agreement for thyroid ultrasound elastography and to analyze the reproducibility of real-time freehand elastography in thyroid nodules.

Methods: A prospective nonrandomized double-blind study was conducted between September 2008 and June 2010. Real-time elastography of 89 thyroid nodules was performed by two radiologists, with the first radiologist evaluating each thyroid nodule 5 minutes before the second.