Imaging for primary hyperparathyroidism - an evidence-based analysis

Imaging in patients with primary hyperparathyroidism has been proven difficult. During the last decade, sestamibi scintigraphy and ultrasound (US) have been used with various success. The importance of these procedures has risen since minimal invasive parathyroid (MIP) surgery also has developed, and it is claimed that preoperative localization usually is needed before embarking on such a procedure. We have scanned the most recent literature in this matter in order to identify evidence, using commonly accepted grading, and also concluded a number of recommendations. We found evidence at level III leading to recommendations at grade B, that sestamibi scintigraphy is a recommended first test, but that US by an experienced investigator may be an alternative. MIP may be performed when both tests are concordant, and in case of only one test being positive, unilateral exploration and use of intraoperative PTH measurements are recommended. Bilateral neck exploration is used when both tests are negative. For reoperative procedures, repeat investigations are recommended, but also to use US-guided fine needle aspiration and PTH measurements as well as venous sampling. However, for reoperative procedures, the level of evidence is weaker-level IV, but recommendations still at grade B.