Kobata Takuya, Norikane Takashi, Murao Mitsumasa, Manabe Yuri, Yamamoto Yuka, Mitamura Katsuya, Hatakeyama Tetsuhiro, Miyake Keisuke, Nishiyama Yoshihiro, Kudomi Nobuyuki
Department of Clinical Radiology, Kagawa University Hospital, 1750-1, Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan.
Department of Radiology, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan.
Ann Nucl Med. 2025 Apr 29. doi: 10.1007/s12149-025-02054-3.
Delayed appearance of blood in the brain may be a pathophysiological indicator of stenosis or occlusion. Image computation for blood appearance generally requires considerable time. Therefore, in this study, we aimed to shorten the computation time using several algorithms and tested their accuracy and precision using examination data and simulations, as well as the computation time.
We retrospectively analyzed the images of patients with suspected cerebrovascular disorders who underwent PET study with O-labeled tracers. The blood appearance time images were computed by fitting a stepwise time-shifted tissue curve and applying a single-tissue compartment model with several modes of fixing or not fixing the washout rate and/or blood volume terms. The appearance times in images for these modes were compared with the time obtained by ROI-based non-linear fitting in several brain regions. The effects of noise and parameter fixation are assessed using a simulation study.
The computation time was 28.2 ± 6.2 min, 16.6 ± 3.9 min, and 2.6 ± 1.1 min for modes without fixing, with fixing blood volume, and washout rate, respectively. The mean difference in the appearance time against ROI-based non-linear fitting was less than 1 s with a standard deviation (SD) of approximately 2.5 s for those modes. The images obtained were similar for all three modes. The simulation showed that SD on the estimated appearance times were acceptable, namely < 1.5 s, for these modes.
This study suggests the possibility of visualizing appearance time images in the brain with a reasonable computation time of approximately 2.5 min at the minimum and 30 min at the most.
脑内血液延迟出现可能是狭窄或闭塞的病理生理指标。血液出现的图像计算通常需要相当长的时间。因此，在本研究中，我们旨在使用几种算法缩短计算时间，并使用检查数据和模拟以及计算时间来测试它们的准确性和精确性。
我们回顾性分析了接受O标记示踪剂PET研究的疑似脑血管疾病患者的图像。通过拟合逐步时间偏移的组织曲线并应用具有几种固定或不固定洗脱率和/或血容量项模式的单组织隔室模型来计算血液出现时间图像。将这些模式图像中的出现时间与通过在几个脑区基于ROI的非线性拟合获得的时间进行比较。使用模拟研究评估噪声和参数固定的影响。
对于不固定、固定血容量和洗脱率的模式，计算时间分别为28.2±6.2分钟、16.6±3.9分钟和2.6±1.1分钟。对于这些模式，与基于ROI的非线性拟合相比，出现时间的平均差异小于1秒，标准差（SD）约为2.5秒。三种模式获得的图像相似。模拟表明，这些模式下估计出现时间的SD是可接受的，即<1.5秒。
本研究表明，有可能以合理的计算时间在脑内可视化出现时间图像，最短约2.5分钟，最长30分钟。
