Parathyroid Adenoma Orientation for Gland Embryologic Origin on Ultrasonography

Area of Science:

• Endocrinology
• Surgical Oncology
• Diagnostic Imaging

Background:

• Accurate preoperative localization of parathyroid adenomas (PTAs) is crucial for successful targeted parathyroidectomy in primary hyperparathyroidism.
• Current localization methods may have limitations, necessitating improved techniques for predicting gland origin.

Purpose of the Study:

• To evaluate the utility of sagittal ultrasonography (US) in predicting the embryologic origin of PTAs based on the angle between the adenoma's long axis and strap musculature.
• To assess the effectiveness of US-based measurements in guiding surgical localization for parathyroidectomy.

Main Methods:

• Diagnostic study utilizing data from the Stanford Research Repository (January 2009 - October 2021).
• Inclusion criteria: patients aged ≥18 years with primary hyperparathyroidism, clear sagittal US view of PTA, and confirmed gland of origin intraoperatively and pathologically.
• Measurement of the angle between the PTA's long axis and strap musculature on sagittal US; analysis of the relationship between PTA and posterior carotid artery border on transverse US.

Main Results:

• Of 442 adenomas, 314 had measurable angles. An optimized angle of 94° demonstrated 74% sensitivity and 72% specificity for differentiating superior from inferior PTAs.
• Using a 90° breakpoint, angulation analysis achieved 72.9% accuracy in determining PTA origin.
• Transverse US analysis using the posterior carotid artery border showed 66.9% accuracy in predicting gland origin.

Conclusions:

• Sagittal US angulation of PTAs is a valuable tool for predicting gland origin and guiding targeted parathyroidectomy.
• Transverse US assessment of the PTA-carotid artery relationship offers an additional method for predicting gland origin.
• These US-based techniques are easily applicable and can complement other imaging modalities for improved surgical planning.