Kim Deok-Hwan, Yoo Eun-Hye, Hong Ui-Seong, Kim Jun-Hyeok, Ko Young-Heon, Moon Seung-Cheol, Cheon Miju, Yoo Jang
Department of Nuclear Medicine, Veterans Health Service Medical Center, Seoul 05368, Korea.
General Electronic Healthcare, Seoul 04637, Korea.
Healthcare (Basel). 2021 Jun 4;9(6):669. doi: 10.3390/healthcare9060669.
We evaluated the benefits of the MotionFree algorithm through phantom and patient studies. The various sizes of phantom and vacuum vials were linked to RPM moving with or without MotionFree application. A total of 600 patients were divided into six groups by breathing protocols and CT scanning time. Breathing protocols were applied as follows: (a) patients who underwent scanning without any breathing instructions; (b) patients who were instructed to hold their breath after expiration during CT scan; and (c) patients who were instructed to breathe naturally. The length of PET/CT misregistration was measured and we defined the misregistration when it exceeded 10 mm. In the phantom tests, the images produced by the MotionFree algorithm were observed to have excellent agreement with static images. There were significant differences in PET/CT misregistration according to CT scanning time and each breathing protocol. When applying the type (c) protocol, decreasing the CT scanning time significantly reduced the frequency and length of misregistrations ( < 0.05). The MotionFree application is able to correct respiratory motion artifacts and to accurately quantify lesions. The shorter time of CT scan can reduce the frequency, and the natural breathing protocol also decreases the lengths of misregistrations.
我们通过体模和患者研究评估了MotionFree算法的益处。将各种尺寸的体模和真空瓶与有或无MotionFree应用时随RPM移动的情况相关联。总共600名患者根据呼吸方案和CT扫描时间分为六组。呼吸方案应用如下：(a) 未接受任何呼吸指示进行扫描的患者；(b) 在CT扫描期间呼气后被指示屏气的患者；以及(c) 被指示自然呼吸的患者。测量PET/CT配准误差的长度，当配准误差超过10毫米时我们定义为配准不良。在体模测试中，观察到MotionFree算法产生的图像与静态图像具有极好的一致性。根据CT扫描时间和每种呼吸方案，PET/CT配准误差存在显著差异。应用类型(c)方案时，缩短CT扫描时间可显著降低配准不良的频率和长度（<0.05）。MotionFree应用能够校正呼吸运动伪影并准确量化病变。CT扫描时间越短可降低频率，自然呼吸方案也可减少配准不良的长度。
