Four-Dimensional Computed Tomography for Parathyroid Adenoma Localization: A Pre-Operative Imaging Protocol

Area of Science:

• Endocrinology
• Radiology
• Surgical Oncology

Background:

• Primary hyperparathyroidism (PHPT) affects nearly 1% of the population, with surgery as the primary treatment.
• 4D computed tomography (CT) is a valuable tool for parathyroid adenoma localization.
• The comparative role of 4D CT against ultrasonography (USG) and SPECT/CT (SES) in PHPT requires definition.

Purpose of the Study:

• To evaluate the effectiveness of 4D CT as a second-line imaging modality for parathyroid adenoma localization in PHPT patients.
• To compare the diagnostic performance of 4D CT with first-line imaging techniques (USG and SES).
• To propose an optimized imaging algorithm for PHPT diagnosis.

Main Methods:

• Retrospective review of 84 PHPT patients who underwent parathyroidectomy between 2014 and 2019.
• Analysis of 4D CT imaging outcomes following unsuccessful first-line USG or SES.
• Comparison of localization accuracy, sensitivity, and specificity across imaging modalities.

Main Results:

• 4D CT correctly localized parathyroid adenomas to the quadrant in 64% and laterality in 75% of cases.
• Ultrasonography showed significantly lower adenoma localization rates in obese patients (33.4%) compared to non-obese patients (67.5%).
• 4D CT demonstrated 86% sensitivity and 87% specificity for detecting multigland disease.

Conclusions:

• 4D CT offers high accuracy in parathyroid adenoma localization but involves radiation exposure.
• Recommended imaging algorithm: USG as first-line, followed by 4D CT for specific indications (age >40, high BMI, revision surgery).
• This approach balances diagnostic efficacy with radiation safety in PHPT management.