Parathyroid localization with modified 4D-computed tomography and ultrasonography for patients with primary hyperparathyroidism.

Objectives: In this article, we report our decade-long experience in using modified 4D-computed tomography in combination with ultrasonography (Mod 4D-CT/US) to localize abnormal parathyroid glands in patients with primary hyperparathyroidism.

Study Design: Retrospective medical record review at a university-based academic medical center.

Methods: Patients with primary hyperparathyroidism who underwent a Mod 4D-CT/US and parathyroidectomy between January 1998 and May 2009 were included in the study. Results from preoperative localization studies were compared with operative findings, pathologic data, and biochemical measurements to assess the sensitivity and specificity as well as the positive and negative predictive values of Mod 4D-CT/US.

Results: Mod 4D-CT/US demonstrated 94% sensitivity and 96% specificity when these imaging studies were used to lateralize the hyperfunctioning parathyroid glands to one side of the neck. In regard to localizing abnormal parathyroid glands to a specific quadrant of the neck (i.e., right-left; superior-inferior), the sensitivity and specificity of Mod 4D-CT/US was 82% and 93%, respectively. Mod 4D-CT/US had a 92% positive predictive value for single-gland disease and 75% for multigland disease. The negative predictive value for single and multigland disease (MGD) were 73% and 92%, respectively.

Conclusions: Mod 4D-CT/US provides excellent sensitivity and specificity in terms of localizing abnormal parathyroid glands to the correct side and quadrant in patients with primary hyperparathyroidism, and it correctly identifies many patients with MGD.