Presentations

Abstract

Introduction:

Parathyroid adenomas are common causes of primary hyperparathyroidism. Preoperative localization of these adenomas is crucial for surgical planning and successful removal. Parathyroid four- dimensional CT (4D CT) is becoming increasingly popular for the diagnosis and localization of parathyroid adenomas. 4D CT harnesses time as the fourth dimension, enabling precise identification and localization of parathyroid adenomas.

Case Information:

We present the case of an 80-year-old female with a past medical history of chronic kidney disease and diabetes mellitus. During routine lab work, her serum calcium was found to be elevated at 11.9 mEq/L. Further workup revealed a serum parathyroid hormone level of 383.4 pg/ml, compatible with primary hyperparathyroidism. A planar scintigraphic sestamibi scan revealed abnormal radiopharmaceutical activity in the region of the left superior parathyroid, suggesting the possibility of parathyroid adenoma versus parathyroid hyperplasia. A 4D CT scan of the neck demonstrated a discrete 1 x 1 x 2 cm nodule along the posterior margin of the left upper pole thyroid with rapid enhancement and rapid washout-characteristics consistent with parathyroid adenoma. Surgical parathyroidectomy was carried out of the left superior, left inferior and right inferior parathyroid glands was performed. Pathology of the left superior parathyroid confirmed tissue diagnosis of parathyroid adenoma.

Discussion:

Traditional imaging techniques have limitations in accurately identifying the location of parathyroid adenomas. 4D CT scan is a reliable tool for the localization of parathyroid adenomas. This advanced imaging technique combines the advantages of computed tomography (CT) scans with dynamic imaging over time, enabling precise visualization of the parathyroid adenoma's vascular supply, its relationship with adjacent structures, and its functional characteristics. An additional benefit is the capability to locate ectopic adenomas in the neck and chest. From a surgical perspective, precise localization can potentially enable the use of smaller incisions and avoid the necessity to examine each parathyroid individually. On 4D CT imaging, parathyroid adenomas typically exhibit distinct characteristics. They often appear as discrete nodules adjacent to or within the thyroid gland, with rapid enhancement upon contrast administration and subsequent rapid washout. These dynamic imaging features, involving both quick uptake and clearance of contrast, aid in the precise identification and localization of parathyroid adenomas, contributing to improved diagnosis and surgical planning.

Conclusion:

This case underscores the value of 4D CT in accurately diagnosing and pinpointing the location of parathyroid adenomas.