The aim of this study was to evaluate the accuracy of multidetector computed tomography (MDCT) in the detection of parathyroid adenoma and hyperplasia in the setting of primary hyperparathyroidism.
Records of 48 patients with biochemically confirmed primary hyperparathyroidism, who underwent preoperative imaging with 16- or 64-slice contrast-enhanced MDCT and subsequent successful parathyroidectomy over a 3-year period, were reviewed. Two radiologists, blinded to the operative and histologic findings, independently evaluated multiplanar computed tomographic images for all patients.
On pathologic examination, 63 abnormal glands were confirmed in 41 female and 7 male patients (mean age, 63 years). Of the 63 abnormal glands, 40 were adenomatous and 23 were hyperplastic. MDCT demonstrated an 88% (95% confidence interval [CI], 77%–99%) positive predictive value for localizing abnormal hyperfunctioning parathyroid glands. The sensitivity of MDCT in detecting single-gland disease was 80% (95% CI, 68%–92%); whereas the specificity for ruling out hyperfunctioning parathyroid tissue, either adenomatous or hyperplastic, was 75% (95% CI, 51%–99%). The sensitivity for exclusively localizing parathyroid hyperplasia was 17% (95% CI, 2%–33%). The parathyroid adenomas were substantially larger and heavier than their hyperplastic counterparts, with an average weight of 1.51 g (range, 0.08–6.00 g) and 0.42 g (range, 0.02–2.0 g) for adenoma and hyperplasia, respectively.
Contrast-enhanced MDCT demonstrated an 88% positive predictive value for localizing adenomatous and hyperplastic parathyroid glands. The poor sensitivity for detection of multigland disease was likely a result of the smaller size and weight of the abnormal hyperplastic glands.