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arXiv 2510.26388physics.med-ph
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脑部PET扫描仪中的头部运动监测

Monitoring Head Movement in a Brain PET Scanner

Machiel Kolstein, Mokhtar Chmeissani, Andreu Pacheco

AI总结:

本研究针对脑部PET扫描中头部运动降低图像质量的问题,提出基于CrowN@22冠状点源监测设备的模拟方案,可在低活度点源与脑部高活度示踪剂共存下实现高精度头部运动检测。

摘要:

在采集PET(正电子发射断层扫描)图像时,由于采集时间可能长达10-20分钟甚至更久,身体运动是不可避免的。这些运动会在图像重建和衰减校正层面严重降低最终图像的质量。运动可能具有节律性模式,与呼吸或心脏运动相关,也可能是患者不适引发的突发性反射动作。目前已开发出许多软件和硬件方法来缓解这一问题,每种方法各有优缺点。在本研究中,我们提出了一项针对头部监测设备CrowN@22的模拟研究,该设备旨在与专用脑部PET扫描仪配合使用。CrowN@22设备由六个非纯正电子发射体同位素(如22Na或44Sc)点源组成,这些点源以冠状环的形式安装在患者头部周围。点源的相对位置是预先设定的,安装完成后可通过标记额外的1274 keV光子(以22Na为例)来重建其实际位置。这两个因素带来了极高的信噪比,能够区分22Na监测点源的信号与脑部FDG(氟代脱氧葡萄糖)产生的背景信号。因此,即便监测点源的活度很低——每个点源低至10 kBq,在脑部存在75 MBq活度的18F的情况下,仍能以1 Hz的采样率检测到脑部运动,精度小于0.3度(或0.5毫米),这一精度处于PET空间分辨率的量级。

英文摘要:

When acquiring PET images, body motions are unavoidable, given that the acquisition time could last 10-20 minutes or more. These motions can seriously deteriorate the quality of the final image at the level of image reconstruction and attenuation corrections. Movements can have rhythmic patterns, related to respiratory or cardiac motions, or they can be abrupt reflexive actions caused by the patient's discomfort. Many approaches, software and hardware, have been developed to mitigate this problem where each approach has its own advantages and disadvantages. In this work we present a simulation study of a head monitoring device, named CrowN@22, intended to be used in conjunction with a dedicated brain PET scanner. The CrowN@22 device consists of six point sources of non-pure positron emitter isotopes, such as 22Na or 44Sc, mounted in crown-like rings around the head of the patient. The relative positions of the point sources are predefined and their actual position, once mounted, can be reconstructed by tagging the extra 1274 keV photon (in the case of 22Na). These two factors contribute to a superb signal-to-noise ratio, distinguishing between the signal from the 22Na monitor point sources and the background signal from the FDG in the brain. Hence, even with a low activity for the monitor point sources, as low as 10 kBq per point source, in the presence of 75 MBq activity of 18F in the brain, one can detect brain movements with a precision of less than 0.3 degrees, or 0.5 mm, which is of the order of the PET spatial resolution, at a sampling rate of 1 Hz.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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