原発性上皮小体機能亢進症の術前局在診断における99mTc-methoxy-isobutyl-isonitrileシンチグラフィの有用性について

Abstract

原発性上皮小体機能亢進症により上皮小体腫瘍摘出術を行い病理組織が確認された18例を対象とした.術後反回神経麻痺等の重篤な合併症を併発した症例は認めなかった.病理組織は全例単発の腺腫で過形成, 癌腫は認めなかった.なお全例術後に血清カルシウム及び上皮小体ホルモンの正常化を認めた.摘出した腺は全部で24腺で腺腫が18腺, 正常上皮小体が6腺であった.局在診断成績は腺腫18腺中17腺が91mTc-methoxy-isobutyl-isonitrile(MIBI)シンチグラフィーで描出された.sensitivityは94.4%, positive predictive value (PPV)は94.4%であった.超音波断層検査ではsensitivityは52.9%, PPVは81.8%であり, MRI検査ではsensitivityは80.0%, PPVは92.3%であった

We evaluated the usefulness of 99mTc-methoxy-isobutyl-isonitrile (MIBI) dual phase scintigraphy for detecting hyperfunctioning parathyroid adenoma. We retrospectively reviewed 18 hyperparathyroid patients who received MIBI prior to neck exploration and compared the radiological findings of MIBI with ultrasonography (US) and magnetic resonance imaging (MRI). Fifteen patients were studied with MRI, and 17 patients were examined with US. All patients were found to have a solitary parathyroid adenoma histopathologically. MIBI correctly revealed the location of 17 adenomas among 18 confirmed tumors. In our series, there was one false-positive case that was found to have thyroid adenoma. The diagnostic sensitivity of MIBI MRI and US was 94.4%, 80% and 52.5%, respectively. The positive predictive value (PPV) was 94.4% for MIBI, 81.8% for MRI and 92.3% for US. We conclude that MIBI is useful and accurate for the preoperative localization of adenoma in primary hyperparathyroidism.