Piga M, Bolasco P, Satta L, Altieri P, Loi G, Nicolosi A, Tarquini A, Mariotti S
Department of Nuclear Medicine, University of Cagliari, Italy.
J Nucl Med. 1996 Apr;37(4):565-9.
Double-phase 99mTc-methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy has been proposed to detect hyperplastic parathyroid tissue, but the clinical usefulness of this technique in secondary hyperparathyroidism is still debated.
Technetium-99m-MIBI parathyroid scintigraphy associated with parathyroid echography and [99mTc]pertechnetate thyroid scans were performed on 38 patients with chronic renal failure (CRF) and secondary hyperparathyroidism. In all patients, serum calcium, phosphorus, FT3, FT4, TSH, calcitonin and intact PTH (iPTH) were determined. Nine patients eventually underwent neck exploration and 28 parathyroid glands were removed.
Thyroid diseases were excluded in all patients. Echography revealed parathyroid enlargement in 22/38 (58%) patients, while MIBI scintigraphy was positive in 28/38 (74%), including 5 ectopic glands. Mean serum iPTH concentration was significantly higher in MIBI-positive glands compared to MIBI-negative glands, but several discrepancies were observed in single patients. A significant positive correlation between serum iPTH and gland size was observed when MIBI-positive, but not MIBI-negative, parathyroids were considered. A paradoxical positive correlation between serum calcium and iPTH concentrations was found in MIBI-positive patients.
Double-phase 99mTc-MIBI scintigraphy is positive in the majority of patients with uremic hyperparathyroidism. Comparison of scintigraphic data with morphological and functional data strongly suggests that 99mTc-MIBI scans do not reveal simple parathyroid enlargement but rather, identify the presence of hyperfunctioning (autonomous) parathyroid tissue suggestive of tertiary hyperparathyroidism.
双相99m锝-甲氧基异丁基异腈（MIBI）甲状旁腺闪烁扫描术已被用于检测增生的甲状旁腺组织，但该技术在继发性甲状旁腺功能亢进中的临床实用性仍存在争议。
对38例慢性肾衰竭（CRF）合并继发性甲状旁腺功能亢进患者进行了99m锝-MIBI甲状旁腺闪烁扫描，并结合甲状旁腺超声检查和[99mTc]高锝酸盐甲状腺扫描。所有患者均测定了血清钙、磷、FT3、FT4、TSH、降钙素和完整甲状旁腺激素（iPTH）。9例患者最终接受了颈部探查，切除了28个甲状旁腺。
所有患者均排除甲状腺疾病。超声检查显示22/38（58%）例患者甲状旁腺增大，而MIBI闪烁扫描阳性者为28/38（74%），其中包括5个异位腺体。与MIBI阴性腺体相比，MIBI阳性腺体的平均血清iPTH浓度显著更高，但在个别患者中观察到了一些差异。当考虑MIBI阳性而非MIBI阴性的甲状旁腺时，血清iPTH与腺体大小之间存在显著正相关。在MIBI阳性患者中发现血清钙与iPTH浓度之间存在矛盾的正相关。
双相99mTc-MIBI闪烁扫描在大多数尿毒症性甲状旁腺功能亢进患者中呈阳性。将闪烁扫描数据与形态学和功能数据进行比较强烈表明，99mTc-MIBI扫描并非显示单纯的甲状旁腺增大，而是识别出提示三发性甲状旁腺功能亢进的功能亢进（自主性）甲状旁腺组织的存在。
