A Unique Use of Intraoperative Digital Specimen Radiography in the Treatment of Primary Hyperparathyroidism

Abstract

Intraoperative evaluation of primary parathyroid specimens historically has been difficult. Frozen section diagnosis is not reliable and time-consuming. A visible rim of compressed normal parathyroid tissue is seen histologically surrounding a parathyroid adenoma and absent in parathyroid hyperplasia. Adjuncts such as radionuclide scanning and intraoperative parathyroid hormone levels help but are indirect methods of evaluation. Intraoperative digital specimen radiography (IDSR) of specimens is a novel technique that was compared with frozen section analysis. The study spanned a 12-month period. Thirty-six patients with primary hyperparathyroidism met eligibility criteria. Resected parathyroid specimens were evaluated with the Bioptics PiXarray100 digital radiograph system and pathologic evaluation. Thirty-nine specimens were evaluated with IDSR, reflecting three patients with multiple glands excised. Thirty patients were pathologically found to have adenomas (83%) and six were hyperplasia (17%). Twenty-seven of 30 adenoma specimens had an IDSR visible rim of compressed tissue (sensitivity 90%) and no hyperplasia specimens had an IDSR visible rim (specificity 100%). Fisher's exact test was significant (P = 0.000). Frozen section correctly diagnosed adenoma in only 16 of 30 specimens (sensitivity 53%). IDSR of parathyroid specimens is a powerful modality in the real-time differentiation of parathyroid adenomas from hyperplasia (sensitivity 90%). This technique is noninferior to the current "gold standard," frozen section (sensitivity 53%). We propose IDSR evaluation of all parathyroid surgical specimens for the immediate diagnosis of adenoma versus hyperplasia.