Ultrasound elastography using carotid artery pulsation in the differential diagnosis of sonographically indeterminate thyroid nodules

AJR Am J Roentgenol. 2015 Feb;204(2):396-401. doi: 10.2214/AJR.14.12871.


OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of gray-scale ultrasound and a new method of thyroid ultrasound elastography using carotid artery pulsation in the differential diagnosis of sonographically indeterminate thyroid nodules. MATERIALS AND METHODS. A total of 102 thyroid nodules with indeterminate gray-scale ultrasound features from 102 patients (20 males and 82 females; age range, 16-74 years; mean age, 51 years) were included. The gray-scale ultrasound images of each nodule were reviewed and assigned a score from 1 (low) to 5 (high) according to the possibility of malignancy. Ultrasound elastography was performed using carotid pulsation as the compression source. The elasticity contrast index (ECI), which quantifies local strain contrast within a nodule, was automatically calculated. The radiologist reassessed the scores after concurrently reviewing gray-scale ultrasound and elastography. ROC curve analysis was used to evaluate the diagnostic performances of each dataset and to compare the AUC (Az) values of gray-scale ultrasound score alone, ECI alone, and a combined assessment. RESULTS. Significantly more malignant thyroid nodules were hypoechoic than benign nodules (p = 0.014). The ECI was significantly higher in malignant nodules than in benign thyroid nodules. The Az values of each dataset were 0.755 (95% CI, 0.660-0.835) for gray-scale ultrasound score, 0.835 (0.748-0.901) for ECI, and 0.853 (0.769-0.915) for a combined assessment. The Az value for a combined assessment of the gray-scale ultrasound score and the ECI was significantly higher than that for the gray-scale ultrasound score alone (p = 0.022). CONCLUSION. Combined assessment with gray-scale ultrasound and elastography using carotid artery pulsation is helpful for characterizing sonographically indeterminate thyroid nodules as benign or malignant.

Keywords: carotid artery pulsation; elastography; thyroid nodule; thyroid ultrasound.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Carotid Arteries / physiopathology*
  • Diagnosis, Differential
  • Elasticity Imaging Techniques*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Pulsatile Flow*
  • Retrospective Studies
  • Thyroid Nodule / diagnostic imaging*
  • Thyroid Nodule / physiopathology*
  • Young Adult