Department of Diagnostic Radiology, Graduate School of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Kumamoto, Kumamoto, 8608550, Japan.
Department of Diagnostic Medical Imaging, School of Health Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Ann Nucl Med. 2020 Jun;34(6):415-423. doi: 10.1007/s12149-020-01464-9. Epub 2020 Apr 16.
The functional imaging methods widely used for the diagnosis of Lewy body disease (LBD) are I-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropan (FP-CIT) with dopamine transporter single photon emission computed tomography (DAT-SPECT) and I-iodobenzylguanidine (MIBG) myocardial scintigraphy. The aim of this study was to determine whether DAT-SPECT or I-MIBG myocardial scintigraphy should be examined first and to evaluate whether the combined use of DAT-SPECT and MIBG myocardial scintigraphy is superior to using either modality alone for diagnosing suspected LBD.
In this retrospective study, a total of 117 patients suspected of having LBD underwent DAT-SPECT imaging followed by MIBG myocardial scintigraphy. The delayed heart-to-mediastinum (H/M) ratio of MIBG scintigraphy, and the specific binding ratio (SBR) of DAT-SPECT imaging, and Combined index (defined as SBR mean × H/M in the delayed phase) were used as semi-quantitative measures. The diagnostic ability was evaluated using these indexes.
The sensitivity, specificity, and accuracy of diagnosing Lewy body disease were 59.6%, 71.4%, and 67.5% by SBR mean of DAT-SPECT, 85.1%, 91.4%, and 88.9% by delayed H/M ratio of MIBG myocardial scintigraphy, 76.6%, 74.3%, and 75.2% by Combined index, respectively.
In the diagnosis of LBD, DAT-SPECT, MIBG myocardial scintigraphy, and Combined index may be reliable indices. In particular, MIBG myocardial scintigraphy was the specific modality for LBD diagnosis. Understanding the effectiveness and limits of DAT-SPECT and MIBG myocardial scintigraphy and using both properly will lead to a more accurate diagnosis and better treatment.
用于诊断路易体疾病（LBD）的功能成像方法广泛使用 I-N-ω-氟丙基-2β-羧甲基-3β-（4-碘苯基）-nortropan（FP-CIT）与多巴胺转运体单光子发射计算机断层扫描（DAT-SPECT）和 I-碘苄胍（MIBG）心肌闪烁显像。本研究的目的是确定应该首先检查 DAT-SPECT 还是 I-MIBG 心肌闪烁显像，并评估 DAT-SPECT 和 MIBG 心肌闪烁显像的联合使用是否优于单独使用任何一种方式来诊断疑似 LBD。
在这项回顾性研究中，共有 117 例疑似 LBD 的患者接受了 DAT-SPECT 成像检查，随后进行了 MIBG 心肌闪烁显像。MIBG 闪烁显像的延迟心脏与纵隔（H/M）比值，以及 DAT-SPECT 成像的特异性结合比值（SBR）和联合指数（定义为延迟期 SBR 均值×H/M）被用作半定量指标。使用这些指标评估诊断能力。
DAT-SPECT 的 SBR 均值诊断 LBD 的灵敏度、特异性和准确率分别为 59.6%、71.4%和 67.5%，MIBG 心肌闪烁显像的延迟 H/M 比值分别为 85.1%、91.4%和 88.9%，联合指数分别为 76.6%、74.3%和 75.2%。
在 LBD 的诊断中，DAT-SPECT、MIBG 心肌闪烁显像和联合指数可能是可靠的指标。特别是，MIBG 心肌闪烁显像对 LBD 诊断具有特异性。了解 DAT-SPECT 和 MIBG 心肌闪烁显像的有效性和局限性，并正确使用这两种方法，将有助于更准确的诊断和更好的治疗。
