Department of Clinical Physiology, Nuclear Medicine, and PET, Copenhagen University Hospital Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.
Department of Clinical Physiology, Nuclear Medicine, and PET, Copenhagen University Hospital Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.
Neuroimage. 2021 Jun;233:117950. doi: 10.1016/j.neuroimage.2021.117950. Epub 2021 Mar 11.
In present study we aimed to validate the use of image-derived input functions (IDIF) in the kinetic modeling of cerebral blood flow (CBF) measured by [O]HO PET by comparing with the accepted reference standard arterial input function (AIF). Additional comparisons were made to mean cohort AIF and CBF values acquired by methodologically independent phase-contrast mapping (PCM) MRI. Using hybrid PET/MRI an IDIF was generated by measuring the radiotracer concentration in the internal carotid arteries and correcting for partial volume effects using the intravascular volume measured from MRI-angiograms. Seven patients with carotid steno-occlusive disease and twelve healthy controls were examined at rest, after administration of acetazolamide, and, in the control group, during hyperventilation. Agreement between the techniques was examined by linear regression and Bland-Altman analysis. Global CBF values modeled using IDIF correlated with values from AIF across perfusion states in both patients (p<10, R=0.82, 95% limits of agreement (LoA)=[-11.3-9.9] ml/100 g/min) and controls (p<10, R=0.87, 95% LoA=[-17.1-13.7] ml/100 g/min). The reproducibility of gCBF using IDIF was identical to AIF (15.8%). Values from IDIF and AIF had equally good correlation to measurements by PCM MRI, R=0.86 and R=0.84, (p<10), respectively. Mean cohort AIF performed substantially worse than individual IDIFs (p<10, R=0.63, LoA=[-12.8-25.3] ml/100 g/min). In the patient group, use of IDIF provided similar reactivity maps compared to AIF. In conclusion, global CBF values modeled using IDIF correlated with values modeled by AIF and similar perfusion deficits could be established in a patient group.
在本研究中，我们旨在通过与公认的参考标准动脉输入函数 (AIF) 进行比较，验证在使用 [O]HO PET 测量脑血流 (CBF) 的动力学建模中使用图像衍生输入函数 (IDIF) 的有效性。还与通过方法独立的相位对比映射 (PCM) MRI 获得的平均队列 AIF 和 CBF 值进行了比较。使用混合 PET/MRI，通过测量颈内动脉中的示踪剂浓度并使用 MRI 血管造影测量的血管内体积校正部分容积效应来生成 IDIF。在休息时、乙酰唑胺给药后以及在对照组中进行过度通气时，对 7 例颈动脉狭窄闭塞性疾病患者和 12 例健康对照者进行了检查。通过线性回归和 Bland-Altman 分析检查了技术之间的一致性。在所有灌注状态下，使用 IDIF 建模的全局 CBF 值与患者（p<10，R=0.82，95%置信区间（LoA）=[-11.3-9.9] ml/100 g/min）和对照组（p<10，R=0.87，95% LoA=[-17.1-13.7] ml/100 g/min）中的 AIF 值相关。使用 IDIF 的 gCBF 重复性与 AIF 相同（15.8%）。IDIF 和 AIF 的值与 PCM MRI 的测量值具有同等良好的相关性，R=0.86 和 R=0.84，（p<10）。平均队列 AIF 的表现明显逊于个体 IDIF（p<10，R=0.63，LoA=[-12.8-25.3] ml/100 g/min）。在患者组中，使用 IDIF 提供了与 AIF 相似的反应性图。总之，使用 IDIF 建模的全局 CBF 值与使用 AIF 建模的值相关，并且可以在患者组中建立相似的灌注缺陷。
