大同小异：采用碲锌镉（CZT）探测器与碘化钠（NaI）探测器的扫描仪上进行的多巴胺转运体单光子发射计算机断层扫描（SPECT）

Same same but different: dopamine transporter SPECT on scanners with CZT vs. NaI detectors.

作者信息

Thiele Felix, Schau Franziska, Rogasch Julian M M, Wetz Christoph, Bluemel Stephanie, Brenner Winfried, Amthauer Holger, Lange Catharina, Schatka Imke

机构信息

Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Berlin, Germany.

Berlin Institute of Health (BIH) at Charité - Universitätsmedizin Berlin, Berlin, Germany.

出版信息

EJNMMI Res. 2023 Mar 22;13(1):24. doi: 10.1186/s13550-023-00973-8.

DOI:10.1186/s13550-023-00973-8

PMID:36949290

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10033816/

Abstract

BACKGROUND

The aims of this study were to establish a normal database (NDB) for semiquantification of dopamine transporter (DAT) single-photon emission computed tomography (SPECT) with [I]FP-CIT on a cadmium zinc telluride (CZT) camera, test the preexisting NaI-derived NDB for use in CZT scans, and compare the diagnostic findings in subjects imaged with a CZT scanner with either the preexisting NaI-based NDB or our newly defined CZT NDB.

METHODS

The sample comprised 73 subjects with clinically uncertain parkinsonian syndrome (PS) who prospectively underwent [I]FP-CIT SPECT on a CZT camera according to standard guidelines with identical acquisition and reconstruction protocols (DaTQUANT). Two experienced readers visually assessed the images and binarized the subjects into "non-neurodegenerative PS" and "neurodegenerative PS". Twenty-five subjects from the "non-neurodegenerative PS" subgroup were randomly selected to establish a CZT NDB. The remaining 48 subjects were defined as "test group". DaTQUANT was used to determine the specific binding ratio (SBR). For the test group, SBR values were transformed to z-scores for the putamen utilizing both the CZT NDB and the manufacturer-provided NaI-based NDB (GE NDB). A predefined fixed cut-off of -2 was used for dichotomization of z-scores to classify neurodegenerative and non-neurodegenerative PS. Performance of semiquantification using the two NDB to identify subjects with neurodegenerative PS was assessed in comparison with the visual rating. Furthermore, a randomized head-to-head comparison of both detector systems was performed semiquantitatively in a subset of 32 out of all 73 subjects.

RESULTS

Compared to the visual rating as reference, semiquantification based on the dedicated CZT NDB led to fewer discordant ratings than the GE NDB in CZT scans (3 vs. 8 out of 48 subjects). This can be attributed to the putaminal z-scores being consistently higher with the GE NDB on a CZT camera (median absolute difference of 1.68), suggesting an optimal cut-off of -0.5 for the GE NDB instead of -2.0. Average binding ratios and z-scores were significantly lower in CZT compared to NaI data.

CONCLUSIONS

Use of a dedicated, CZT-derived NDB is recommended in [I]FP-CIT SPECT with a CZT camera since it improves agreement between semiquantification and visual assessment.

摘要

背景

本研究的目的是建立一个正常数据库（NDB），用于在碲化镉锌（CZT）相机上对使用[I]FP-CIT的多巴胺转运体（DAT）单光子发射计算机断层扫描（SPECT）进行半定量分析，测试现有的基于碘化钠（NaI）的NDB在CZT扫描中的适用性，并将使用CZT扫描仪成像的受试者的诊断结果与现有的基于NaI的NDB或我们新定义的CZT NDB进行比较。

方法

样本包括73例临床帕金森综合征（PS）诊断不明确的受试者，他们根据标准指南在CZT相机上前瞻性地接受了[I]FP-CIT SPECT检查，采用相同的采集和重建方案（DaTQUANT）。两名经验丰富的阅片者对图像进行视觉评估，并将受试者分为“非神经退行性PS”和“神经退行性PS”。从“非神经退行性PS”亚组中随机选择25名受试者建立CZT NDB。其余48名受试者被定义为“测试组”。使用DaTQUANT确定特异性结合率（SBR）。对于测试组，利用CZT NDB和制造商提供的基于NaI的NDB（GE NDB）将壳核的SBR值转换为z分数。使用预先定义的固定临界值-2对z分数进行二分法，以区分神经退行性和非神经退行性PS。与视觉评级相比，评估使用两个NDB进行半定量分析以识别神经退行性PS受试者的性能。此外，在所有73名受试者中的32名受试者的子集中对两种探测器系统进行了半定量的随机头对头比较。

结果

与作为参考的视觉评级相比，在CZT扫描中，基于专用CZT NDB的半定量分析导致的不一致评级少于基于GE NDB的分析（48名受试者中分别为3例和8例）。这可归因于在CZT相机上使用GE NDB时壳核的z分数始终较高（中位数绝对差为1.68），这表明GE NDB的最佳临界值为-0.5而非-2.0。与NaI数据相比，CZT中的平均结合率和z分数显著更低。