Role of Preoperative Diagnostic Imaging Procedures in Secondary Hyperparathyroidism

Parathyroid imaging has been widely used for the identification and localization of abnormal parathyroid adenomas in patients with suspected primary hyperparathyroidism and for preoperative and reoperative localization. However, recently developed methods of functional imaging, like 99mTc-sestamibi parathyroid scan combined with routine anatomic procedures, provide additional quantitative and qualitative information on various types and stages of parathyroid hyperplasia which is the common presentation of secondary hyperparathyroidism. This kind of information could not only prove useful in preoperative diagnosis, but also in the selection of medical or surgical therapeutic alternatives in secondary hyperparathyroidism patients. Our group found a significant correlation between 99mTcsestamibi uptake and parathormone blood levels but no correlation was found with other determinants of hyperparathyroidism. This finding demonstrates that scintigraphy accurately reflects the gland activity independently from other biochemical parameters that could be influencing gland secretion. It is reasonable to assume that better preoperative information will ease the detection of hyperplastic glands and reduce operative time and surgical trauma. This review discusses the role of non-invasive imaging modalities prior to surgery, and also in the clinical management of patients with secondary hyperparathyroidism.