Comparing reference points in strain elastography for predicting autoimmune thyroiditis

Area of Science:

• Radiology
• Thyroid Imaging
• Diagnostic Ultrasound

Background:

• Chronic autoimmune thyroiditis is associated with increased thyroid stiffness.
• Sternocleidomastoid (SCM) or strap muscles have been used as reference points in strain elastography.
• The choice of reference point may impact diagnostic accuracy.

Purpose of the Study:

• To compare the diagnostic performance of strain elastography for autoimmune thyroiditis using different reference points.
• To evaluate the influence of sternocleidomastoid (SCM) muscle versus trachea as reference points.
• To determine the optimal reference point for assessing thyroid stiffness in autoimmune thyroiditis.

Main Methods:

• Strain elastography was performed on non-tumor-bearing thyroid parenchyma in patients scheduled for thyroidectomy.
• The strain ratio was calculated using either the adjacent sternocleidomastoid (SCM) muscle or the trachea as the reference point.
• Pathological results served as the gold standard for diagnosis.

Main Results:

• Autoimmune thyroiditis was diagnosed in 39 out of 174 patients (22%).
• The strain ratio using the trachea as a reference, along with thyroid antibodies, independently predicted thyroiditis.
• The area under the ROC curve was significantly higher when using the trachea (0.854) compared to the SCM (0.611).

Conclusions:

• The choice of reference point in strain elastography critically affects the prediction of autoimmune thyroiditis.
• Utilizing the trachea as a reference point significantly enhances the diagnostic performance of strain elastography for autoimmune thyroiditis.
• Diagnostic accuracy was not influenced by patient age or body habitus.