Center for Amyloidosis and Acute Phase Proteins, University College London Medical School, London, UK.
Br Med Bull. 2013;107:41-56. doi: 10.1093/bmb/ldt021. Epub 2013 Jul 29.
Diagnosis of systemic amyloidosis remains challenging. Histology, the current gold standard for diagnosis of amyloidosis provides limited information on the extent of the disease and is not useful for monitoring. Non-invasive imaging modalities offer an easy way to evaluate whole-body amyloid burden, accurately identify organ involvement, quantify and monitor disease progression and response to treatment.
A literature search was performed using PubMed on the subjects of 'amyloid imaging', 'SAP scintigraphy', 'imaging in cardiac amyloidosis', 'cardiac MRI', 'PET and amyloidosis' and 'nuclear imaging in amyloidosis'.
¹²³I-SAP scintigraphy is the best and the only modality in routine clinical use for assessing the extent and distribution of visceral amyloid deposition in all types of amyloidosis. Echocardiography remains the most important tool for assessing cardiac amyloidosis but cardiac magnetic resonance imaging is becoming increasingly valuable. Bone-seeking tracers like 99mTc-DPD and pyrophosphate are beginning to have a role in imaging transthyretin cardiac amyloidosis.
Specificity of each of the imaging modalities limits the utility of any one imaging method for all types of amyloidosis for all organs. GROWING POINTS AND FURTHER RESEARCH: 99mTc-DPD has a high sensitivity and specificity to cardiac transthyretin amyloid deposits and its role in early diagnosis of this condition is under investigation. Further studies are needed with ¹²³I-mIBG to assess its utility in patients with early cardiac autonomic neuropathy. Positron emission tomography with tracers used for Alzheimer's disease imaging is an area of increasing interest in systemic amyloid imaging.
系统性淀粉样变性的诊断仍然具有挑战性。组织学是目前淀粉样变性诊断的金标准，但只能提供有限的疾病范围信息，且无法用于监测。非侵入性成像方式为评估全身淀粉样负荷提供了一种简便的方法，可以准确识别器官受累情况，定量和监测疾病进展以及对治疗的反应。
使用 PubMed 以“淀粉样蛋白成像”、“SAP 闪烁显像”、“心脏淀粉样变性的影像学”、“心脏 MRI”、“PET 和淀粉样变性”和“淀粉样变性的核成像”为主题进行文献检索。
¹²³I-SAP 闪烁显像术是评估所有类型淀粉样变性中内脏淀粉样沉积程度和分布的最佳且唯一的常规临床应用方法。超声心动图仍然是评估心脏淀粉样变性的最重要工具，但心脏磁共振成像的价值越来越大。放射性核素骨显像剂如 99mTc-DPD 和焦磷酸盐开始在成像转甲状腺素蛋白心脏淀粉样变性中发挥作用。
每种成像方式的特异性限制了任何一种成像方法在所有类型淀粉样变性的所有器官中的应用。
99mTc-DPD 对心脏转甲状腺素蛋白淀粉样沉积物具有高灵敏度和特异性，目前正在研究其在该疾病早期诊断中的作用。¹²³I-mIBG 在评估早期心脏自主神经病变患者中的作用需要进一步研究。用于阿尔茨海默病成像的示踪剂正电子发射断层扫描是系统性淀粉样成像中日益受到关注的领域。
