Shear Wave Elastography versus Strain Elastography in Diagnosing Parathyroid Adenomas.

Area of Science:

• Radiology
• Medical Imaging
• Endocrinology

Background:

• Parathyroid adenomas are the most common cause of primary hyperparathyroidism.
• Accurate preoperative localization is crucial for successful surgical management.
• Elastography techniques offer potential for non-invasive tissue characterization.

Purpose of the Study:

• To compare the efficacy of shear wave elastography (SWE) and strain elastography (SE) in identifying parathyroid adenomas.
• To establish quantitative elastographic parameters for differentiating parathyroid adenomas from surrounding tissues.

Main Methods:

• Prospective study of 20 patients with confirmed parathyroid adenomas.
• Conventional ultrasound, 2D SWE, and SE were performed.
• Elasticity index (EI) measured by SWE in parathyroid adenoma, thyroid, and muscle.
• Strain ratio determined by SE comparing parathyroid adenoma to thyroid and muscle tissue.

Main Results:

• SWE showed significantly lower mean EI in parathyroid adenomas (4.74 kPa) compared to thyroid (11.72 kPa) and muscle (16.36 kPa) (p < 0.001).
• An EI cutoff of < 7 kPa demonstrated high accuracy in identifying parathyroid tissue via ROC analysis.
• SE strain ratio did not show a statistically significant correlation with thyroid tissue (p=0.485).

Conclusions:

• Ultrasound elastography, particularly 2D SWE, is a valuable tool for parathyroid adenoma identification.
• A 2D SWE EI cutoff of < 7 kPa is proposed for diagnostic use.
• SE color mapping, without strain ratio, can assist in diagnosis, with parathyroid adenomas correlating to Rago score 1.