采用 BGO 晶体的 PET/CT 相机对霍奇金淋巴瘤进行 [18F]FDG 显像的最佳活性。

Optimal activity of [18F]FDG for Hodgkin lymphoma imaging performed on PET/CT camera with BGO crystals.

机构信息

Affidea PET/CT Warsaw, Poland.

Department of Nuclear Medicine, Military Institute of Medicine, Warsaw, Poland.

出版信息

Nucl Med Rev Cent East Eur. 2022;25(1):47-53. doi: 10.5603/NMR.a2022.0009.

DOI:10.5603/NMR.a2022.0009

PMID:35137937

Abstract

BACKGROUND

We aimed to find the minimum feasible activity of fluorodeoxyglucose ([18F]FDG) in positron emission tomography/computed tomography (PET/CT) of Hodgkin lymphoma patients performed on a camera with bismuth germanate (BGO) crystals.

MATERIAL AND METHODS

Ninety-one [18F]FDG PET/CT scans (each in seven Bayesian Penalized Likelihood [BPL] reconstructions with varying acquisition time per bed position - 2 min, 1.5 min, 1 min, 50 s, 40 s, 30 s, and 20 s) were independently assessed by three physicians to evaluate image quality. Mean administered activity was 3.0 ± 0.1 MBq/kg and mean uptake time was 54.0 ± 8.7 min. The series quality was subjectively marked on a 1-10 scale and then ranked 1-7 based on the mean mark. Interobserver rank correlation and intraclass correlation within each series for the three observers were calculated. Phantom studies were also performed to determine if reduced acquisition time can be directly translated into a reduced activity.

RESULTS

Time series were marked and ranked unanimously - the longer the time of acquisition the higher the mark and rank. The interobserver agreement in the ranking was excellent (100%) with a kappa coefficient of 1.00 (95% CI [0.83-1.0]). The general intraclass correlation coefficient (agreement between the marks observers gave each time series) was very high (0.945, 95% CI [0.936-0.952]) and was higher the shorter the time per bed. According to all three observers only the series with 2 min and 1.5 min acquisition time were appropriate for assessment (mean mark ≥ 7). In phantom studies there was a linear correlation between time per bed, administered activity, and number of total prompts detected by a scanner. Hence, a reduction of acquisition time of 25% (from 2 min to 1.5 min) could be directly translated into a 25% activity reduction (from 3.0 to 2.25 MBq/kg).

CONCLUSIONS

In patients with HL, [18F]FDG activity can be reduced by up to 25% when using a BGO crystal camera, without substantial impact on image quality.

摘要

背景

我们旨在寻找在使用锗酸铋（BGO）晶体的正电子发射断层扫描/计算机断层扫描（PET/CT）中，霍奇金淋巴瘤患者的氟脱氧葡萄糖 ([18F]FDG) 的最小可行活性。

材料和方法

91 次 [18F]FDG PET/CT 扫描（每个扫描都有 7 种不同采集时间的贝叶斯惩罚似然法 [BPL] 重建，每个床位位置的采集时间分别为 2 分钟、1.5 分钟、1 分钟、50 秒、40 秒、30 秒和 20 秒）由三位医生独立评估，以评估图像质量。平均给予的活性为 3.0 ± 0.1 MBq/kg，平均摄取时间为 54.0 ± 8.7 分钟。系列质量在 1-10 标度上主观标记，然后根据平均标记值从 1-7 进行排名。计算了三位观察者在每个系列中的组内观察者间等级相关性和组内相关性。还进行了体模研究，以确定采集时间的缩短是否可以直接转化为活性的降低。

结果

时间序列一致标记和排名 - 采集时间越长，标记和排名越高。观察者之间的排名一致性非常好（100%），kappa 系数为 1.00（95%CI[0.83-1.0]）。总体组内相关系数（观察者给每个时间序列的标记之间的一致性）非常高（0.945，95%CI[0.936-0.952]），并且随时间缩短而增加床。根据所有三位观察者的意见，只有采集时间为 2 分钟和 1.5 分钟的系列适合评估（平均标记值≥7）。在体模研究中，床时间、给予的活性和扫描仪检测到的总提示数之间存在线性关系。因此，采集时间减少 25%（从 2 分钟减少到 1.5 分钟）可以直接转化为活性减少 25%（从 3.0 减少到 2.25 MBq/kg）。