Hwang Sang Hyun, Rhee Yumie, Yun Mijin, Yoon Jung Hyun, Lee Jeong Won, Cho Arthur
Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722 South Korea.
Department of Internal Medicine, Severance Hospital, Endocrine Research Institute, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722 South Korea.
Nucl Med Mol Imaging. 2017 Mar;51(1):32-39. doi: 10.1007/s13139-016-0438-5. Epub 2016 Jul 28.
Parathyroid adenoma detection with dual-phase Tc-sestamibi (MIBI) scintigraphy depends on differential MIBI washout from thyroid. However, autoimmune thyroid disease (AITD) may cause MIBI to be retained in the thyroid gland and reduce parathyroid detection. We evaluated the impact of AITD on MIBI thyroid retention and additional benefit of SPECT/CT in these patients.
Dual phase planar MIBI and SPECT/CT was performed on 82 patients. SPECT/CT was performed immediately after delayed planar scan. Thyroid density (Hounsfield unit, CT-HU) and size were measured on CT component of SPECT/CT. MIBI uptake in early scans and retention in delayed scans were visually graded and correlated with clinical factors and CT findings. Finally, planar and SPECT/CT findings were compared for parathyroid lesion visualization according to thyroid MIBI retention.
In early scan, multivariate analysis showed only thyroid size predicted early uptake. In delayed scan, multivariate analysis showed higher visual grade in early scan, lower CT-HU or AITD were significant predictors for delayed thyroid parenchymal retention. Overall, ten more parathyroid lesions were visualized on SPECT/CT compared to planar scans (57 vs. 47, = 0.002). SPECT/CT was especially more useful in patients with thyroidal MIBI retention, as eight out of the ten additional lesions detected were found in patients with thyroid MIBI retention.
AITD is an important factor for MIBI thyroid parenchymal retention on delayed scans, and may impede parathyroid lesion detection. Patients with MIBI retention in the thyroid parenchyma on delayed scans are likely to benefit from an additional SPECT/CT.
双期锝-司他美比（MIBI）闪烁扫描检测甲状旁腺腺瘤依赖于甲状腺对MIBI的不同清除情况。然而，自身免疫性甲状腺疾病（AITD）可能导致MIBI在甲状腺内滞留，从而降低甲状旁腺的检出率。我们评估了AITD对MIBI甲状腺滞留的影响以及SPECT/CT在这些患者中的额外益处。
对82例患者进行双期平面MIBI和SPECT/CT检查。延迟平面扫描后立即进行SPECT/CT检查。在SPECT/CT的CT部分测量甲状腺密度（亨氏单位，CT-HU）和大小。对早期扫描中的MIBI摄取和延迟扫描中的滞留情况进行视觉分级，并与临床因素和CT结果相关联。最后，根据甲状腺MIBI滞留情况，比较平面和SPECT/CT检查对甲状旁腺病变的显示情况。
在早期扫描中，多因素分析显示只有甲状腺大小可预测早期摄取。在延迟扫描中，多因素分析显示早期扫描中视觉分级较高、CT-HU较低或患有AITD是甲状腺实质延迟滞留的重要预测因素。总体而言，与平面扫描相比，SPECT/CT多显示出10个甲状旁腺病变（57个对47个，P = 0.002）。SPECT/CT在甲状腺MIBI滞留的患者中尤其有用，因为在额外检测到的10个病变中有8个是在甲状腺MIBI滞留的患者中发现的。
AITD是延迟扫描中MIBI甲状腺实质滞留的重要因素，可能会妨碍甲状旁腺病变的检测。延迟扫描中甲状腺实质内有MIBI滞留的患者可能会从额外的SPECT/CT检查中获益。
