Parathyroid Scintigraphy in Primary and Secondary Hyperparathyroidism: Accuracy of Preoperative Localisation Using Combined Imaging Techniques
HT Tam, YH Wong, SK Cheung, WT Ngai, PT Choi
Hong Kong J Radiol 2010;13:59-67
Objective: To evaluate the accuracy of preoperative parathyroid scintigraphy for lesion localisation in primary and secondary hyperparathyroidism.
Methods: The archives of 3 regional Hong Kong hospitals extending over a 12-month period were retrospectively reviewed for parathyroid scintigraphies in subjects who underwent subsequent first-time parathyroidectomy. Scintigraphic techniques comprised early- and late-phase 99mTc-sestamibi planar imaging (100% of studies), emission computed tomography (97%), and supplementary 99mTc-pertechnetate thyroid imaging (13%). Images were re-interpreted by applying a scoring scale to different lesional locations. Accuracies were determined by operative and histological findings.
Results: This series was based on 19 patients with primary hyperparathyroidismlesions (23 lesions) and 19 with secondary hyperparathyroidism associated with chronic renal failure (70 lesions). The frequencies of primary lesions in left upper, left lower, right upper, right lower, and ectopic positions were 13%, 30%, 9%, 44%, and 4% respectively; corresponding figures for secondary lesions were 24%, 24%, 26%, 23%, and 3%. The sensitivity, specificity, positive predictive, and negative predictive values of scintigraphy for locating primary lesions were 91%, 99%, 96%, and 97% respectively; and for secondary lesions corresponding figures were 74%, 84%, 93%, and 54%. The corresponding overall results for all lesions were 79%, 95%, 94%, and 82%.
Conclusions: Preoperative scintigraphy for localising hyperfunctioning parathyroids has a better accuracy in primary than secondary hyperparathyroidism (97% vs. 77%). Primary lesions have a preponderance for lower positions (74%) and may be subjected to scintigraphy-guided minimally invasive parathyroidectomy. The lower sensitivity (74%) and negative predictive value (54%) for secondary lesions render scintigraphy less helpful in secondary hyperparathyroidism, except on rare occasions to locate ectopic lesions.
中文摘要
原發性及繼發性甲狀旁腺機能亢進症的核素顯像：使用綜合影像技術作術前定位檢查的準確度
譚曉東、黃月紅、張盛基、魏偉達、蔡柏達
目的：評估甲狀旁腺核素顯像對原發性及繼發性甲狀旁腺機能亢進症作術前病變定位檢查的準確程度。
方法：回顧香港三間地區醫院在12個月的研究期內首次進行甲狀旁腺切除的患者的核素顯像圖。核素顯像包括早期及晚期99mTc-sestamibi平面成像術（100%），發射電腦斷層攝影術（97%），和補充性99mTc-pertechnetate甲狀腺顯像術（13%）。利用評分表再次替不同病變位置的影像重新闡釋，然後對比手術結果及病理學結果來計算攝影術對病變定位的準確度。
結果：研究包括19名原發性甲狀旁腺機能亢進症患者（共23個病灶），另有19名並發慢性腎衰竭的繼發性甲狀旁腺機能亢進症患者（共70個病灶）。累及腺體的位置分為左上、左下、右上、右下和異位，原發性病變發生在這些位置的比率分別為13%、30%、9%、44%和4%，而繼發性病變發生在
這些位置的比率分別為24%、24%、26%、23%和3%。核素顯像對原發性病變定位的敏感性、特異性、陽性預測率和陰性預測率分別為91%、99%、96%和97%；對於繼發性病變分別為74%、84%、93%和54%；總結果分別為79%、95%、94%和82%。
結論：對於甲狀旁腺機能亢進症的病變定位，術前核素顯像對原發性病變的準確度比繼發性的高（97%比77%）。大部分原發性病變出現在腺體下部的位置（74%），可由核素顯像引導微創甲狀旁腺切除術進行治療。由於核素顯像對繼發性甲狀旁腺機能亢進症的敏感性（74%）和陰性預測率（54%）都偏低，對定位幫助不如原發性病變，但它偶爾也可對異位病變作定位。