AbstractResting cerebral perfusion metrics can be calculated from the MRI ΔR2* signal during the first passage of an intravascular bolus of a Gadolinium-based contrast agent (GBCA), or more recently, a transient hypoxia-induced change in the concentration of deoxyhemoglobin ([dOHb]). Conventional analysis follows a proxy process that includes deconvolution of an arterial input function (AIF) in a tracer kinetic model.

摘要静息脑灌注指标可以从基于钆的造影剂（GBCA）的血管内推注的第一次通过期间的MRIΔR2*信号计算，或者最近，瞬时缺氧引起的脱氧血红蛋白浓度变化（[dOHb]）。常规分析遵循代理过程，该过程包括示踪剂动力学模型中动脉输入函数（AIF）的反卷积。

We hypothesized that the step reduction in magnetic susceptibility accompanying a step decrease in [dOHb] that occurs when a single breath of oxygen terminates a brief episode of lung hypoxia permits direct calculation of relative perfusion metrics. The time course of the ΔR2* signal response enables both the discrimination of blood arrival times and the time course of voxel filling.

我们假设，当单次呼吸氧气终止短暂的肺部缺氧时，伴随着[dOHb]的逐步降低，磁化率的逐步降低允许直接计算相对灌注指标。ΔR2*信号响应的时间过程可以区分血液到达时间和体素填充的时间过程。

We calculated the perfusion metrics implied by this step signal change in seven healthy volunteers and compared them to those from conventional analyses of GBCA and dOHb using their AIF and indicator dilution theory. Voxel-wise maps of relative cerebral blood flow and relative cerebral blood volume had a high spatial and magnitude congruence for all three analyses (r > 0.9) and were similar in appearance to published maps.

我们计算了七名健康志愿者的这种阶跃信号变化所暗示的灌注指标，并使用其AIF和指示剂稀释理论将其与GBCA和dOHb的常规分析进行了比较。相对脑血流量和相对脑血容量的体素地图在所有三种分析中都具有很高的空间和幅度一致性（r>0.9），并且在外观上与已发布的地图相似。

The mean (SD) transit times (s) in grey and white matter respectively for the step response (7.4 (1.1), 8.05 (1.71)) were greater than those for GBCA (2.6 (0.45), 3.54 (0.83)) attributable to the nature of their respective calculation models. In conclusion we believe these calculations of perfusion metrics derived directly from ΔR2* have superior merit to calculations via AIF by virtue of being calculated from a direct signal rather than through a proxy model which encompasses errors inherent in designating an AIF and performing deconvolution calculations..

阶跃响应（7.4（1.1），8.05（1.71））分别在灰质和白质中的平均（SD）通过时间（s）大于GBCA（2.6（0.45），3.54（0.83））归因于它们各自的计算模型的性质。总之，我们认为直接从ΔR2*得出的灌注指标的这些计算优于通过AIF进行的计算，因为它们是从直接信号而不是通过代理模型计算的，该代理模型包含指定AIF和执行反卷积计算所固有的错误。。

IntroductionDynamic susceptibility contrast magnetic resonance perfusion imaging interrogates the voxel-wise passage of a bolus of a susceptibility contrast agent such as a gadolinium-based contrast agent (GBCA), to measure resting cerebral perfusion metrics including relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and mean capillary transit time (MTT).

引言动态磁化率对比磁共振灌注成像询问磁化率造影剂（如钆基造影剂（GBCA））推注的体素方向通过，以测量静息脑灌注指标，包括相对脑血流量（rCBF），相对脑血容量（rCBV）和平均毛细血管通过时间（MTT）。

Analysis of GBCA data for hemodynamic measures follows a vascular model-based approach requiring the deconvolution of a tissue concentration time series with a measured arterial input function (GBCA-AIF analysis)1. The AIF is based on the strength and temporal evolution of a ΔR2* signal, sampled in an arterial region of interest such as the middle cerebral artery2,3,4 or choroid plexus5 where the voxel may be entirely contained in the vessel.Recent reports describe the use of transient hypoxia-induced changes in deoxyhemoglobin concentration (THx-dOHb) as an endogenously-generated contrast agent6,7,8,9,10,11,12,13.

用于血液动力学测量的GBCA数据分析遵循基于血管模型的方法，需要用测量的动脉输入函数（GBCA-AIF分析）1对组织浓度时间序列进行反卷积。AIF基于ΔR2*信号的强度和时间演变，该信号在感兴趣的动脉区域（例如大脑中动脉2,3,4或脉络丛5）中采样，其中体素可能完全包含在血管中。最近的报道描述了使用瞬时缺氧诱导的脱氧血红蛋白浓度变化（THx-dOHb）作为内源性产生的造影剂6,7,8,9,10,11,12,13。

Changes in arterial deoxyhemoglobin concentrations ([dOHb]) are produced by targeting the alveolar partial pressures of oxygen (PO2) via changes in the PO2 of inspired gases14,15,16,17. The calculation of resting perfusion metrics using THx-dOHb as a contrast agent is similar to that for GBCA, i.e. an indicator dilution method18 with an AIF (THx-dOHb-AIF).

动脉脱氧血红蛋白浓度（[dOHb]）的变化是通过吸入气体PO2的变化来靶向肺泡氧分压（PO2）产生的[14,15,16,17]。。

This analysis calculates the concentration of contrast agent in the voxel via the deconvolution of the tissue signal with an AIF. THx-dOHb-AIF analysis has been shown to generate resting perfusion metrics that are comparable to those obtained using GBCA-AIF analysis in healthy participants11, patients with steno-occlusive disease19, and patients with brain tumors20.For the reoxygenation phase, there is a remarkable anatomical-phys.

该分析通过用AIF对组织信号进行反卷积来计算体素中造影剂的浓度。已显示THx-dOHb AIF分析产生的静息灌注指标与健康参与者11，狭窄闭塞性疾病患者19和脑肿瘤患者20中使用GBCA-AIF分析获得的指标相当。对于复氧阶段，有一个显着的解剖生理。

(1)

(1)

where S, the ΔR2* signal in a voxel; C, a proportionality constant; CBV, the volume of blood in a voxel; SaO2, the arterial oxygen saturation; [Hb], the arterial hemoglobin concentration (assumed to be 130 g/L unless measured).SaO2 is related to arterial PO2 (PaO2) by the in-vivo oxygen dissociation curve24.

其中S，体素中的ΔR2*信号；C、 比例常数；CBV，体素中的血容量；SaO2，动脉血氧饱和度；[Hb]，动脉血红蛋白浓度（除非测量，否则假定为130 g/L）。SaO2通过体内氧解离曲线与动脉PO2（PaO2）相关24。

Equation (2) describes the relation.$$S_{a} O_{2} = \frac{{K \times PO_{2}^{ n} }}{{\left( {1 + K \times PO_{2}^{ n} } \right)}}$$.

等式（2）描述了这种关系$$S{a}O{2}=\frac{{K次PO{2}^{n}}{{\左（{1+K次PO{2}^{n}}\右）}}$$。

(2)

(2)

where n and K are derived from a Levenburg-Marquardt fit to measured human data24:$${\text{K }} = { 5} \times {1}0^{{ - {142}}} \times \, \left( {{\text{pH}}} \right)^{{{157}.{31}}}$$$${\text{n }} = \, - {4}.{4921 } \times {\text{ pH }} + { 36}.{365}$$pH is assumed to be 7.4 unless measured.A step increase in alveolar PO2, from approximately 40 to 95 mmHg, produces a step increase in SaO2 from 75 to 97%.

其中n和K来自Levenburg-Marquardt，适合测量的人类数据24：$${\ text{K}}={5}\次{1}0^{{-{142}}\次\，\左（{\文本{pH}}}\右）^{{{{157}。{31}}$$$${\文本{n}}=\，-{4}。{4921}\次{\文本{pH}}+{36}。除非进行测量，否则假定{365}$$pH为7.4。肺泡PO2从大约40 mmHg逐步增加到95 mmHg，SaO2从75%逐步增加到97%。

The change in signal as oxygenated blood displaces the deoxygenated blood in the voxel reflects the hemodynamic parameters of the voxel, which it is our intent to measure.Current models for voxel-wise analysis of hemodynamicsThe two models commonly used to describe the process of displacement of one indicator with another are illustrated in Fig. 2.

随着含氧血液取代体素中的脱氧血液，信号的变化反映了体素的血流动力学参数，这是我们想要测量的。用于血流动力学体素分析的当前模型图2示出了通常用于描述一个指标与另一个指标位移过程的两个模型。

If the voxel is viewed as a compartment, the contents of which undergo instantaneous mixing with the inflowing indicator25 as illustrated in Fig. 2A, the signal intensity response to a step change in susceptibility contrast agent such as dOHb reflects the balance of contrast agent in the course of the exchange.

如果将体素视为一个隔室，其内容物与流入的指示剂25瞬时混合，如图2A所示，则对敏感性造影剂（如dOHb）阶跃变化的信号强度响应反映了造影剂在交换过程中的平衡。

In the case of a high [dOHb] in the voxel and a low [dOHb] in the inflow, the initial high rate of signal intensity decline falls off exponentially as the difference in inflow and outflow of contrast declines to zero. The time constant of this exponential is MTT. Thus, model Fig. 2A describes the central volume theorem where MTT = CBV/CBF.

在体素中的高[dOHb]和流入中的低[dOHb]的情况下，随着对比度流入和流出的差异降至零，信号强度下降的初始高速率呈指数下降。这个指数的时间常数是MTT。因此，模型图2A描述了中心体积定理，其中MTT=CBV/CBF。

This is a generic kinetic model for unknown patterns of blood flow through the tissues and is applied for the calculation of perfusion metrics using the GBCA-AIF and THx-dOHb-AIF analyses8.Figure 2Step response models. (A) Instantaneous Homogeneity. Blood with decreased contrast agent [dOHb] enters a well-mixed container, so that the initial high rate of decrease of [.

这是通过组织的未知血流模式的通用动力学模型，并用于使用GBCA-AIF和THx-dOHb-AIF分析8计算灌注指标。图2步骤响应模型。（A） 瞬时均匀性。造影剂（dOHb）减少的血液进入混合良好的容器，因此最初的高下降率为[。

(3)

(3)

First, the images from the THx-dOHb and GBCA acquisitions were analyzed using a conventional kinetic model-based approach8. The visibly sharpest signal change over a middle cerebral artery was selected as the AIF and a deconvolution-based kinetic model of the type shown in Fig. 2A was used to calculate voxel-wise maps of MTT and rCBV.

首先，使用传统的基于动力学模型的方法分析来自THx-dOHb和GBCA采集的图像8。选择大脑中动脉上明显最尖锐的信号变化作为AIF，并使用图2A所示类型的基于反卷积的动力学模型来计算MTT和rCBV的体素方向图。

Standard tracer kinetic modeling was used to calculate MTT and rCBV as stated in Eq. (4).$${\triangle\text{R}}_{{2}} *\left( {\text{t}} \right) = \left( {{\text{rCBV }}/{\text{ MTT}}} \right) \, \times {\text{ AIF}}\left( {\text{t}} \right) \otimes {\text{R}}\left( {\text{t}} \right) \, + \beta {1 } \times {\text{ t }} + \beta {2 } + \varepsilon ({\text{t}})$$.

如等式（4）所述，使用标准示踪剂动力学建模来计算MTT和rCBV$${\三角形\文本{R}}{2}}*\左（{\文本{t}}\右）=\左（{\文本{rCBV}/{\文本{MTT}}\右）\，\次{\文本{AIF}\左（{\文本{t}\右）\次{\文本{R}\左（{\文本{t}}\右）\，+。\ beta{1}\ times{\ text{t}}+\ beta{2}+\ varepsilon（{\ text{t}}）$$。

(4)

(4)

where t, time; β1 and β2 account for linear signal drift and baseline t respectively; ε(t) represents the residuals; R(t) = e-(1/MTT) the residue function (Fig. 2A).The residue function was set equal to 1 at time 0 and 0 at time equal to 5 × MTT and bound between 1 and 8 s. Metrics rCBV and MTT were determined using a least square fitting procedure.

其中t，时间；β1和β2分别解释了线性信号漂移和基线t；ε（t）表示残差；R（t）=e-（1/MTT）残基函数（图2A）。残基函数在时间0时设置为1，在时间等于5×MTT时设置为0，并在1至8 s之间绑定。使用最小二乘拟合程序确定指标rCBV和MTT。

rCBF was then calculated as the ratio rCBV/MTT using the central volume theorem, (Fig. 2A). Values of rCBV and rCBF were respectively multiplied by 10 and 50 to obtain easily readable values within the range of absolutes measures.Second, the voxel-wise analysis of the ΔR2* signal during the THx-dOHb step protocol was implemented using a custom analysis program (LabVIEW, National Instruments, Texas) as illustrated in Fig. 4.

然后使用中心体积定理将rCBF计算为rCBV/MTT的比率（图2A）。rCBV和rCBF的值分别乘以10和50，以获得绝对测量范围内易于读取的值。其次，如图4所示，使用定制分析程序（LabVIEW，National Instruments，Texas）对THx-dOHb step协议期间的ΔR2*信号进行体素分析。

As Fig. 9 illustrates, the step change in arterial PO2, via reoxygenation from a hypoxic PetO2 of approximately 40 to 95 mmHg, produces a step increase in SaO2, and consequently a step decrease in [dOHb]. The ΔR2* signal in a voxel decreases as blood as the increased SaO2 displaces that at the hypoxic SaO2.

如图9所示，通过从约40至95 mmHg的低氧PetO2复氧，动脉PO2的阶跃变化产生SaO2的阶跃增加，并因此产生[dOHb]的阶跃降低。体素中的ΔR2*信号随着血液的增加而减少，因为增加的SaO2取代了低氧SaO2。

A reference cursor is placed by eye (a in Fig. 11) where the whole brain average ΔR2* signal begins to decrease in response to the step increase in SaO2 and acts as a time reference for all voxels for calculating relative arrival time rBAT.The THx-dOHb Step analysis, explained in Fig. 11, proceeds as follows: For each voxel, a selected portion of the ΔR2* signal response (Fig. 11, red dots in black squares) before and after the reference cursor (a in Fig. 11) is fitted with the Gompertz fit function (Fig. 11, red line) specified in Eq. (5) using the Levenburg-Marquardt algorithm (National Instruments, Texas, LabVIEW), with R-squared indicating the goodness of fit.

用眼睛放置参考光标（图11中的A），其中全脑平均ΔR2*信号随着SaO2的阶跃增加而开始减小，并作为所有体素的时间参考，用于计算相对到达时间rBAT。图11中解释的THx-dOHb阶跃分析如下进行：对于每个体素，在参考光标（图11中的A）之前和之后，ΔR2*信号响应的选定部分（图11，黑色方块中的红点）使用Levenburg-Marquardt算法（National Instruments）拟合方程（5）中指定的Gompertz拟合函数（图11，红线）（德克萨斯州，LabVIEW），R平方表示拟合优度。

Fitting a function to .

将函数拟合到。

(5)

(5)

where S = ΔR2*; t, time; Sfit(t), the fitted ΔR2* signal time course of the step response; exp, power of e; Sbase, the initial value of Sfit(t); a, the magnitude of the S decrease; b, the displacement along the time axis; c, the rate of change.Perfusion metrics rCBV, rCBF and rBAT are all calculated independently as shown in Fig. 11 from the Gompertz function fit to the ΔR2* signal step response, Sfit(t).

其中S = ΔR2*；t、 时间；；exp，e的幂；Sbase，Sfit（t）的初始值；a、 S下降的幅度；b、 沿时间轴的位移；c、 变化率。灌注指标rCBV，rCBF和rBAT都是独立计算的，如图11所示，从Gompertz函数拟合到ΔR2*信号阶跃响应Sfit（t）。

MTT is the time range of the line fit (blue dashed line in Fig. 11), which equals rCBV/rCBF. Gompertz function fit parameter “a” measures the complete decrease in the ΔR2* step response to calculate rCBV. The start of the ΔR2* decrease (Fig. 11, green vertical line) identifies the time where Sfit(t) begins to decrease by 2% of rCBV.

MTT是线拟合的时间范围（图11中的蓝色虚线），其等于rCBV/rCBF。Gompertz函数拟合参数“a”测量ΔR2*阶跃响应的完全降低以计算rCBV。ΔR2*减少的开始（图11，绿色垂直线）标识了Sfit（t）开始减少rCBV 2%的时间。

Relative blood arrival time, rBAT, is calculated as the difference of start time (b) minus reference time (a), with negative values signifying earlier arrival.The maximum rate of decrease of the ΔR2* signal step response is calculated from the Sfit(t) parameters as “a × c/e” to measure rCBF, where e is the base of natural logarithms.

相对血液到达时间rBAT计算为开始时间（b）减去参考时间（a）的差值，负值表示较早到达。ΔR2*信号阶跃响应的最大下降率由Sfit（t）参数计算为“a××c/e”，以测量rCBF，其中e是自然对数的基。

A line with this slope is drawn through the time of maximum slope, “ln(b)/c” (Fig. 11, blue dashed line). It defines three temporal regions, as indicated by the green arrows in Fig. 11. First, the exponential increase in the rate of decline of the ΔR2* signal as the step change in SaO2 arrives at the voxel until the change has entered the voxel in all capillaries; second, a linear portion of the ΔR2* signal decline as all vessels fill with the change in SaO2 until the change begins to leave the voxel; third, an exponential decay in the rate of decline of the ΔR2* signal as the SaO2 change leaves the voxel.

。它定义了三个时间区域，如图11中的绿色箭头所示。首先，随着SaO2的阶跃变化到达体素，ΔR2*信号的下降速率呈指数增长，直到变化进入所有毛细血管中的体素；其次，随着所有血管充满SaO2的变化，ΔR2*信号的线性部分下降，直到变化开始离开体素；第三，随着SaO2的变化离开体素，ΔR2*信号的下降速率呈指数衰减。

MTT is the sum of the time constants of the first and third temporal regions plus the time.

MTT是第一个和第三个时间区域的时间常数加上时间的总和。

Data availability

数据可用性

Anonymized data will be shared by request from any qualified investigator for purposes such as replicating procedures and results presented in the article provided that data transfer is in agreement with the University Health Network and Health Canada legislation on the general data protection regulation..

匿名数据将根据任何合格研究人员的请求共享，以复制本文中介绍的程序和结果，前提是数据传输符合大学健康网络和加拿大卫生部关于一般数据保护法规的立法。。

AbbreviationsAIF:

缩写AIF：

Arterial input function

动脉输入功能

ANOVA:

方差分析：

Analysis of variance

方差分析

FRC:

FRC：

Functional residual capacity

功能剩余容量

GBCA:

GBCA：

Gadolinium-based contrast agents

钆基造影剂

MTT:

MTT法：

Mean transit time

PCO2

二氧化碳

:

:

Partial pressure of carbon dioxide

二氧化碳分压

PO2

PO2

:

:

Partial pressure of oxygen

氧分压

PaO2

PaO2

:

:

Partial pressure of oxygen in arterial blood

动脉血中的氧分压

rCBF:

循环流化床：

Relative cerebral blood flow

相对脑血流量

rCBV:

rCBV：

Relative cerebral blood volume

相对脑血容量

S:

S：

The ΔR2* signal in a voxel

体素中的ΔR2*信号

SaO2

血氧饱和度

:

:

Arterial hemoglobin oxygen saturation

动脉血红蛋白血氧饱和度

THx-dOHb:

THx dOHb：

Transient hypoxia-induced deoxyhemoglobin

短暂缺氧诱导的脱氧血红蛋白

THx-dOHb-AIF:

THx dOHb AIF：

Transient hypoxia-induced deoxyhemoglobin analyzed using an arterial input function

使用动脉输入功能分析短暂缺氧诱导的脱氧血红蛋白

THx-dOHb-Step:

THX-DOHB-STEP：

Transient hypoxia-induced deoxyhemoglobin analyzed using the step reoxygenation (recovery)

使用逐步复氧（恢复）分析瞬时缺氧诱导的脱氧血红蛋白

ReferencesChappell, M. A., Mehndiratta, A. & Calamante, F. Correcting for large vessel contamination in dynamic susceptibility contrast perfusion MRI by extension to a physiological model of the vasculature. Magn. Reson. Med. 74, 280–290. https://doi.org/10.1002/mrm.25390 (2015).Article

参考文献Chappell，M.A.，Mehndiratta，A。＆Calamante，F。通过扩展到脉管系统的生理模型来校正动态磁化率对比灌注MRI中的大血管污染。马格纳。雷森。。https://doi.org/10.1002/mrm.25390（2015年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Calamante, F. Arterial input function in perfusion MRI: A comprehensive review. Prog. Nucl. Magn. Reson. Spectrosc. 74, 1–32. https://doi.org/10.1016/j.pnmrs.2013.04.002 (2013).Article

Calamante，F。灌注MRI中的动脉输入功能：全面综述。程序。核。马格纳。雷森。光谱。74，1-32。https://doi.org/10.1016/j.pnmrs.2013.04.002（2013年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Bleeker, E. J., Webb, A. G., van Walderveen, M. A., van Buchem, M. A. & van Osch, M. J. Evaluation of signal formation in local arterial input function measurements of dynamic susceptibility contrast MRI. Magn. Reson. Med. 67, 1324–1331. https://doi.org/10.1002/mrm.23120 (2012).Article .

Bleeker，E.J.，Webb，A.G.，van Walderveen，M.A.，van Buchem，M.A。＆van Osch，M.J。动态磁化率对比MRI局部动脉输入功能测量中信号形成的评估。Magn。雷森。医学671324-1331。https://doi.org/10.1002/mrm.23120（2012年）。文章。

PubMed

PubMed

Google Scholar

谷歌学者

Shiroishi, M. S. et al. Principles of T2 *-weighted dynamic susceptibility contrast MRI technique in brain tumor imaging. J. Magn. Reson. Imaging 41, 296–313. https://doi.org/10.1002/jmri.24648 (2015).Article

Shiroishi，M.S.等人。脑肿瘤成像中T2*加权动态磁化率对比MRI技术的原理。J、 马格纳。雷森。成像41296-313。https://doi.org/10.1002/jmri.24648（2015年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Sobczyk, O. et al. The choroid plexus as an alternative locus for the identification of the arterial input function for calculating cerebral perfusion metrics using MRI. Am. J. Neuroradiol. 45, 44–50. https://doi.org/10.3174/ajnr.A8099 (2024).Article

Sobczyk，O.等人。脉络丛作为使用MRI计算脑灌注指标的动脉输入功能识别的替代基因座。Am.J.Neuroradiol。45，44-50。https://doi.org/10.3174/ajnr.A8099（2024年）。文章

Google Scholar

谷歌学者

Coloigner, J. et al. Transient hypoxia model revealed cerebrovascular impairment in anemia using BOLD MRI and near-infrared spectroscopy. J. Magn. Reson. Imaging https://doi.org/10.1002/jmri.27210 (2020).Article

Coloigner，J。等人。短暂性缺氧模型使用BOLD MRI和近红外光谱显示贫血中的脑血管损伤。J、 马格纳。雷森。成像https://doi.org/10.1002/jmri.27210（2020年）。文章

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Vu, C. et al. Quantitative perfusion mapping with induced transient hypoxia using BOLD MRI. Magn. Reson. Med. 85, 168–181. https://doi.org/10.1002/mrm.28422 (2021).Article

Vu，C.等人。使用BOLD MRI诱导短暂缺氧的定量灌注图。Magn。雷森。医学85168-181。https://doi.org/10.1002/mrm.28422（2021年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Poublanc, J. et al. Perfusion MRI using endogenous deoxyhemoglobin as a contrast agent: Preliminary data. Magn. Reson. Med. 86, 3012–3021. https://doi.org/10.1002/mrm.28974 (2021).Article

Poublanc，J.等人。使用内源性脱氧血红蛋白作为造影剂的灌注MRI：初步数据。马格纳。雷森。医学863012-3021。https://doi.org/10.1002/mrm.28974（2021年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Lee, D., Le, T. T., Im, G. H. & Kim, S.-G. Whole-brain perfusion mapping in mice by dynamic BOLD MRI with transient hypoxia. J. Cereb. Blood Flow Metab. https://doi.org/10.1177/0271678X221117008 (2022).Article

Lee，D.，Le，T.T.，Im，G.H.＆Kim，S.-G。通过动态BOLD MRI在短暂缺氧条件下对小鼠进行全脑灌注成像。J、 塞雷布。血流代谢。https://doi.org/10.1177/0271678X221117008（2022年）。文章

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Bhogal, A. A. et al. Quantifying cerebral blood arrival times using hypoxia-mediated arterial BOLD contrast. NeuroImage 261, 119523. https://doi.org/10.1016/j.neuroimage.2022.119523 (2022).Article

Bhogal，A.A.等人。使用缺氧介导的动脉BOLD对比定量脑血到达时间。神经影像261119523。https://doi.org/10.1016/j.neuroimage.2022.119523（2022年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Sayin, E. S. et al. Investigations of hypoxia-induced deoxyhemoglobin as a contrast agent for cerebral perfusion imaging. Hum. Brain Mapp. 44, 1019–1029. https://doi.org/10.1002/hbm.26131 (2023).Article

Sayin，E.S.等人。缺氧诱导的脱氧血红蛋白作为脑灌注成像造影剂的研究。嗯。大脑地图。441019-1029年。https://doi.org/10.1002/hbm.26131。文章

PubMed

PubMed

Google Scholar

谷歌学者

Schulman, J. B. et al. DSC MRI in the human brain using deoxyhemoglobin and gadolinium—simulations and validations at 3T. Fnimg 2023, 2. https://doi.org/10.3389/fnimg.2023.1048652 (2023).Article

。Fnimg 2023，2。https://doi.org/10.3389/fnimg.2023.1048652。文章

Google Scholar

谷歌学者

Vu, C. et al. Contrast-free dynamic susceptibility contrast using sinusoidal and bolus oxygenation challenges. NMR Biomed. 2024, e5111. https://doi.org/10.1002/nbm.5111 (2024).Article

Vu，C.等人。使用正弦和推注氧合挑战的无对比度动态磁化率对比。NMR生物医学。2024年，第5111页。https://doi.org/10.1002/nbm.5111（2024年）。文章

CAS

中科院

Google Scholar

谷歌学者

Slessarev, M. et al. Prospective targeting and control of end-tidal CO2 and O2 concentrations. J. Physiol. 581, 1207–1219 (2007).Article

Slessarev，M.等人，《呼气末CO2和O2浓度的前瞻性靶向和控制》。J、 生理学。5811207-1219（2007）。文章

CAS

中科院

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Ito, S. et al. Non-invasive prospective targeting of arterial PCO2 in subjects at rest. J. Physiol. 586, 3675–3682 (2008).Article

Ito，S.等人。休息时受试者动脉PCO2的无创前瞻性靶向。J.Physiol。5863675–3682（2008）。文章

CAS

中科院

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Fierstra, J. et al. Non-invasive accurate measurement of arterial PCO2 in a pediatric animal model. J. Clin. Monit. Comput. 27, 147–155. https://doi.org/10.1007/s10877-012-9403-8 (2013).Article

Fierstra，J.等人。儿科动物模型中动脉PCO2的无创精确测量。J、 临床。莫尼特。计算机。27147-155。https://doi.org/10.1007/s10877-012-9403-8（2013年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Fisher, J. A., Iscoe, S. & Duffin, J. Sequential gas delivery provides precise control of alveolar gas exchange. Respir. Physiol. Neurobiol. 225, 60–69. https://doi.org/10.1016/j.resp.2016.01.004 (2016).Article

Fisher，J.A.，Iscoe，S。＆Duffin，J。顺序气体输送可精确控制肺泡气体交换。呼吸。生理学。神经生物学。225，60-69。https://doi.org/10.1016/j.resp.2016.01.004（2016年）。文章

CAS

中科院

Google Scholar

谷歌学者

Meier, P. & Zierler, K. L. On the theory of the indicator-dilution method for measurement of blood flow and volume. J. Appl. Physiol. 6, 731–744 (1954).Article

Meier，P。＆Zierler，K.L。关于用于测量血流量和体积的指示剂稀释法的理论。J、 应用。生理学。6731-744（1954）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Sayin, E. S. et al. Assessing perfusion in steno-occlusive cerebrovascular disease using transient hypoxia-induced deoxyhemoglobin as a dynamic susceptibility contrast agent. AJNR Am. J. Neuroradiol. 45, 37–43. https://doi.org/10.3174/ajnr.A8068 (2023).Article

Sayin，E.S.等人。使用瞬时缺氧诱导的脱氧血红蛋白作为动态敏感性造影剂评估狭窄闭塞性脑血管疾病的灌注。AJNR Am.J.神经放射学。45，37-43。https://doi.org/10.3174/ajnr.A8068。文章

PubMed

PubMed

Google Scholar

谷歌学者

Vittorio-Stumpo, E. S. S. et al. Transient deoxyhemoglobin formation as a contrast for perfusion MRI studies in patients with brain tumors: A feasibility study. Front. Physiol. https://doi.org/10.3389/fphys.2024.1238533 (2024).Article

Vittorio Stumpo，E.S.S.等人。瞬时脱氧血红蛋白形成作为脑肿瘤患者灌注MRI研究的对比：可行性研究。正面。生理学。https://doi.org/10.3389/fphys.2024.1238533（2024年）。文章

Google Scholar

谷歌学者

Yamaguchi, K., Tsuji, T., Aoshiba, K., Nakamura, H. & Abe, S. Anatomical backgrounds on gas exchange parameters in the lung. World J. Respirol. 9, 8–29. https://doi.org/10.5320/wjr.v9.i2.8] (2019).Article

Yamaguchi，K.，Tsuji，T.，Aoshiba，K.，Nakamura，H。＆Abe，S。肺部气体交换参数的解剖学背景。世界J.Respirol。9，8-29。https://doi.org/10.5320/wjr.v9.i2.8]（2019年）。文章

Google Scholar

谷歌学者

Zhao, K. et al. Physiological system analysis of the kidney by high-temporal-resolution T2 * monitoring of an oxygenation step response. Magn. Reson. Med. 85, 334–345. https://doi.org/10.1002/mrm.28399 (2021).Article

赵，K。等。通过高时间分辨率T2*监测氧合阶跃反应对肾脏进行生理系统分析。马格纳。雷森。医学85334-345。https://doi.org/10.1002/mrm.28399（2021年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Blockley, N. P. et al. Field strength dependence of R1 and R2 relaxivities of human whole blood to ProHance, vasovist, and deoxyhemoglobin. Magn. Reson. Med. 60, 1313–1320. https://doi.org/10.1002/mrm.21792 (2008).Article

Blockley，N.P.等人，《人全血R1和R2弛豫率对增强、血管活性和脱氧血红蛋白的场强依赖性》。Magn。雷森。医学601313-1320。https://doi.org/10.1002/mrm.21792（2008年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Balaban, D. Y. et al. The in-vivo oxyhaemoglobin dissociation curve at sea level and high altitude. Respir. Physiol. Neurobiol. 186, 45–52. https://doi.org/10.1016/j.resp.2012.12.011 (2013).Article

。呼吸。生理学。神经生物学。186，45-52。https://doi.org/10.1016/j.resp.2012.12.011（2013年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Calamante, F. et al. The physiological significance of the time-to-maximum (Tmax) parameter in perfusion MRI. Stroke 41, 1169–1174. https://doi.org/10.1161/STROKEAHA.110.580670 (2010).Article

Calamante，F.等人，《灌注MRI中最大时间（Tmax）参数的生理意义》。中风411169-1174。https://doi.org/10.1161/STROKEAHA.110.580670（2010年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Jespersen, S. N. & Ostergaard, L. The roles of cerebral blood flow, capillary transit time heterogeneity, and oxygen tension in brain oxygenation and metabolism. J. Cereb. Blood Flow Metab. 32, 264–277 (2012).Article

Jespersen，S.N。＆Ostergaard，L。脑血流，毛细血管通过时间异质性和氧张力在脑氧合和代谢中的作用。J、 塞雷布。血流代谢。32264-277（2012）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Newbould, R. D. et al. Perfusion mapping with multiecho multishot parallel imaging EPI. Magn. Reson. Med. 58, 70–81. https://doi.org/10.1002/mrm.21255 (2007).Article

Newbould，R.D.等人。多回波多回波并行成像EPI灌注成像。马格纳。雷森。医学58，70-81。https://doi.org/10.1002/mrm.21255（2007年）。文章

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Watabe, T. et al. CBF/CBV maps in normal volunteers studied with (15)O PET: A possible index of cerebral perfusion pressure. Neurosci. Bull. 30, 857–862. https://doi.org/10.1007/s12264-013-1458-0 (2014).Article

Watabe，T。等人。用（15）O PET研究的正常志愿者的CBF/CBV图：脑灌注压的可能指标。神经科学。公牛。30857-862。https://doi.org/10.1007/s12264-013-1458-0（2014年）。文章

CAS

中科院

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Grandin, C. B., Bol, A., Smith, A. M., Michel, C. & Cosnard, G. Absolute CBF and CBV measurements by MRI bolus tracking before and after acetazolamide challenge: Repeatabilily and comparison with PET in humans. NeuroImage Orlando, Fla 26, 525–535. https://doi.org/10.1016/j.neuroimage.2005.02.028 (2005).Article .

Grandin，C.B.，Bol，A.，Smith，A.M.，Michel，C。＆Cosnard，G。通过MRI推注追踪乙酰唑胺激发前后的绝对CBF和CBV测量：可重复性以及与人类PET的比较。佛罗里达州奥兰多神经影像公司26525-535。https://doi.org/10.1016/j.neuroimage.2005.02.028（2005年）。文章。

Google Scholar

谷歌学者

Ibaraki, M. et al. Cerebral vascular mean transit time in healthy humans: A comparative study with PET and dynamic susceptibility contrast-enhanced MRI. J. Cereb. Blood Flow Metab. 27, 404–413. https://doi.org/10.1038/sj.jcbfm.9600337 (2007).Article

Ibaraki，M.等人，《健康人的脑血管平均通过时间：与PET和动态磁化率对比增强MRI的比较研究》。J.Cereb。血流代谢。27404-413。https://doi.org/10.1038/sj.jcbfm.9600337（2007年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Asaduddin, M., Do, W.-J., Kim, E. Y. & Park, S.-H. Mapping cerebral perfusion from time-resolved contrast-enhanced MR angiographic data. Magn. Reson. Imaging 61, 143–148. https://doi.org/10.1016/j.mri.2019.05.040 (2019).Article

Asaduddin，M.，Do，W.-J.，Kim，E.Y。和Park，S.-H。从时间分辨对比增强MR血管造影数据绘制脑灌注图。马格纳。雷森。成像61143-148。https://doi.org/10.1016/j.mri.2019.05.040（2019年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Grüner, J. M., Paamand, R., Højgaard, L. & Law, I. Brain perfusion CT compared with15O-H2O-PET in healthy subjects. EJNMMI Res. 1, 28. https://doi.org/10.1186/2191-219X-1-28 (2011).Article

Grüner，J.M.，Paamand，R.，Højgaard，L。＆Law，I。脑灌注CT与15O-H2O-PET在健康受试者中的比较。EJNMMI第1、28号决议。https://doi.org/10.1186/2191-219X-1-28。文章

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Wenzel, J. et al. Impaired endothelium-mediated cerebrovascular reactivity promotes anxiety and respiration disorders in mice. Proc. Natl. Acad. Sci. 117, 1753. https://doi.org/10.1073/pnas.1907467117 (2020).Article

Wenzel，J。等人。内皮介导的脑血管反应性受损会促进小鼠的焦虑和呼吸障碍。程序。纳特尔。阿卡德。科学。1171753年。https://doi.org/10.1073/pnas.1907467117（2020年）。文章

ADS

广告

CAS

中科院

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Artzi, M. et al. Human cerebral blood volume measurements using dynamic contrast enhancement in comparison to dynamic susceptibility contrast MRI. Neuroradiology 57, 671–678. https://doi.org/10.1007/s00234-015-1518-4 (2015).Article

Artzi，M.等人。与动态磁化率对比MRI相比，使用动态对比增强测量人脑血容量。神经放射学57671-678。https://doi.org/10.1007/s00234-015-1518-4（2015年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Ostergaard, L. et al. Cerebral blood flow measurements by magnetic resonance imaging bolus tracking: Comparison with [(15)O]H2O positron emission tomography in humans. J. Cereb. Blood Flow Metab. 18, 935–940. https://doi.org/10.1097/00004647-199809000-00002 (1998).Article

Ostergaard，L。等人。通过磁共振成像推注追踪测量脑血流量：与人类[（15）O]H2O正电子发射断层扫描的比较。J、 塞雷布。血流代谢。18935-940年。https://doi.org/10.1097/00004647-199809000-00002（1998年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Helenius, J. et al. Cerebral hemodynamics in a healthy population measured by dynamic susceptibility contrast MR imaging. Acta Radiol. 44, 538–546. https://doi.org/10.1034/j.1600-0455.2003.00104.x (2003).Article

Helenius，J.等人。通过动态磁化率对比MR成像测量健康人群的脑血流动力学。放射学报。44538-546。https://doi.org/10.1034/j.1600-0455.2003.00104.x（2003年）。文章

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Fieselmann, A., Kowarschik, M., Ganguly, A., Hornegger, J. & Fahrig, R. Deconvolution-based CT and MR brain perfusion measurement: Theoretical model revisited and practical implementation details. Int. J. Biomed. Imaging 2011, 467563. https://doi.org/10.1155/2011/467563 (2011).Article .

Fieselmann，A.，Kowarschik，M.，Ganguly，A.，Hornegger，J。＆Fahrig，R。基于反卷积的CT和MR脑灌注测量：重新审视理论模型和实际实施细节。Int.J.生物医学。成像2011467563。https://doi.org/10.1155/2011/467563。文章。

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Sayin, E. S. et al. Transfer function analysis assesses resting cerebral perfusion metrics using hypoxia-induced deoxyhemoglobin as a contrast agent. Front. Physiol. 2023, 14. https://doi.org/10.3389/fphys.2023.1167857 (2023).Article

Sayin，E.S.等人。传递函数分析使用缺氧诱导的脱氧血红蛋白作为造影剂来评估静息脑灌注指标。正面。生理学。2023年，14。https://doi.org/10.3389/fphys.2023.1167857。文章

Google Scholar

谷歌学者

Mardimae, A. et al. The interaction of carbon dioxide and hypoxia in the control of cerebral blood flow. Eur. J. Physiol. 464, 345–351 (2012).Article

Mardimae，A。等人。二氧化碳和缺氧在控制脑血流中的相互作用。Eur.J.Physiol。464345-351（2012）。文章

CAS

中科院

Google Scholar

谷歌学者

Yang, H.-J. et al. Free-breathing, motion-corrected, highly efficient whole heart T2 mapping at 3T with hybrid radial-cartesian trajectory. Magn. Reson. Med. 75, 126–136. https://doi.org/10.1002/mrm.25576 (2016).Article

Yang，H.-J.等人。自由呼吸，运动校正，高效的3T全心T2映射，混合径向笛卡尔轨迹。马格纳。雷森。医学75126-136。https://doi.org/10.1002/mrm.25576（2016年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Loai, S. et al. Microvascular dysfunction in skeletal muscle precedes myocardial vascular changes in diabetic cardiomyopathy: Sex-dependent differences. Front. Cardiovasc. Med. 2022, 9. https://doi.org/10.3389/fcvm.2022.886687 (2022).Article

Loai，S.等人。糖尿病心肌病中骨骼肌微血管功能障碍先于心肌血管改变：性别依赖性差异。正面。心血管。医学2022，9。https://doi.org/10.3389/fcvm.2022.886687（2022年）。文章

CAS

中科院

Google Scholar

谷歌学者

Fisher, J. A. The CO2 stimulus for cerebrovascular reactivity: Fixing inspired concentrations vs. targeting end-tidal partial pressures. J. Cereb. Blood Flow Metabol. 36, 1004–1011. https://doi.org/10.1177/0271678x16639326 (2016).Article

Fisher，J.A。脑血管反应性的CO2刺激：固定吸入浓度与靶向潮气末分压。J、 塞雷布。血流代谢。361004-1011年。https://doi.org/10.1177/0271678x16639326（2016年）。文章

CAS

中科院

Google Scholar

谷歌学者

Fierstra, J. et al. End-inspiratory rebreathing reduces the end-tidal to arterial PCO(2) gradient in mechanically ventilated pigs. Intensive Care Med. 37, 1543–1550 (2011).Article

Fierstra，J。等人。吸气末再呼吸可降低机械通气猪的呼气末至动脉PCO（2）梯度。重症监护医学371543-1550（2011）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Cox, R. W. AFNI: Software for analysis and visualization of functional magnetic resonance neuroimages. Comput. Biomed. Res. 29, 162–173 (1996).Article

Cox，R。W。AFNI：用于功能磁共振神经图像分析和可视化的软件。计算机。生物医学。。文章

ADS

广告

CAS

中科院

PubMed

PubMed

Google Scholar

谷歌学者

Sobczyk, O. et al. Assessing cerebrovascular reactivity abnormality by comparison to a reference atlas. J. Cereb. Blood Flow Metab. 35, 213–220. https://doi.org/10.1038/jcbfm.2014.184 (2015).Article

Sobczyk，O.等人通过与参考图谱的比较来评估脑血管反应性异常。J、 塞雷布。血流代谢。35213-220。https://doi.org/10.1038/jcbfm.2014.184（2015年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Sobczyk, O. et al. The reproducibility of cerebrovascular reactivity across MRI scanners. Front. Physiol. 12, 668662–668662. https://doi.org/10.3389/fphys.2021.668662 (2021).Article

Sobczyk，O.等人。MRI扫描仪中脑血管反应性的可重复性。正面。生理学。12668662–668662。https://doi.org/10.3389/fphys.2021.668662（2021年）。文章

PubMed

PubMed

PubMed Central

公共医学中心

Google Scholar

谷歌学者

Nowinski, W. L. The cerefy brain atlases. Neuroinformatics 3, 293–300. https://doi.org/10.1385/NI:3:4:293 (2005).Article

Nowinski，W.L。cerefy大脑地图集。神经信息学3293-300。https://doi.org/10.1385/NI:3:4:293（2005年）。文章

PubMed

PubMed

Google Scholar

谷歌学者

Download referencesAuthor informationAuthors and AffiliationsDepartment of Physiology, University of Toronto, Toronto, ON, CanadaJames Duffin, Ece Su Sayin & Joseph A. FisherDepartment of Anaesthesia and Pain Management, University Health Network, Toronto, CanadaJames Duffin, Olivia Sobczyk & Joseph A.

下载参考文献作者信息作者和附属机构多伦多大学生理学系，安大略省多伦多市，加拿大詹姆斯·达芬，Ece Su Sayin＆Joseph A.菲舍尔大学健康网络麻醉与疼痛管理系，多伦多，加拿大詹姆斯·达芬，奥利维亚·索布奇克＆Joseph A。

FisherJoint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, CanadaOlivia Sobczyk, Julien Poublanc & David J. MikulisToronto General Hospital Research Institute, University Health Network, University of Toronto, Toronto, CanadaJoseph A. FisherAuthorsJames DuffinView author publicationsYou can also search for this author in.

多伦多大学健康网络医学影像学和功能神经影像学实验室FisherJoint系，加拿大多伦多大学健康网络大学医学影像学和功能神经影像学实验室，加拿大多伦多大学，Julien Poublanc＆David J.Mikulistoron综合医院研究所，加拿大多伦多大学，Joseph A.FisherAuthorsJames DuffinView作者出版物您也可以在中搜索这位作者。

PubMed Google ScholarEce Su SayinView author publicationsYou can also search for this author in

PubMed谷歌学术评论Su SayinView作者出版物您也可以在

PubMed Google ScholarOlivia SobczykView author publicationsYou can also search for this author in

PubMed Google ScholarOlivia SobczykView作者出版物您也可以在

PubMed Google ScholarJulien PoublancView author publicationsYou can also search for this author in

PubMed谷歌学者Julien PoublancView作者出版物您也可以在

PubMed Google ScholarDavid J. MikulisView author publicationsYou can also search for this author in

PubMed Google ScholarDavid J.MikulisView作者出版物您也可以在

PubMed Google ScholarJoseph A. FisherView author publicationsYou can also search for this author in

PubMed谷歌学者Joseph A.FisherView作者出版物您也可以在

PubMed Google ScholarContributionsJAF conceived the study and JD implemented the analyses. DJM selected and reviewed all subjects for suitability. ESS, OS and JP executed the experiments to acquire the data. JD and ESS analysed the data. JD, ESS and JAF wrote the initial draft of the manuscript.

PubMed Google ScholarContributionsJAF构思了这项研究，JD实施了分析。DJM选择并审查了所有科目的适用性。ESS，OS和JP进行了实验以获取数据。JD和ESS分析了数据。JD，ESS和JAF撰写了手稿的初稿。

All authors participated in the preparation and revision of the final version of the manuscript.Corresponding authorCorrespondence to.

所有作者都参与了稿件最终版本的准备和修订。对应作者对应。

James Duffin.Ethics declarations

詹姆斯·达芬。道德宣言

Competing interests

相互竞争的利益

JAF and DJM contributed to the development of the automated end-tidal targeting device, RespirAct™ (Thornhill Medical (TM)) in the company. OS, ESS and JD receive salary support from TM. TM provided no other support for the study. All other authors have no disclosures to report.

JAF和DJM为公司开发自动呼气末靶向装置RespirAct™（Thornhill Medical（TM））做出了贡献。OS，ESS和JD从TM获得工资支持。TM没有为研究提供其他支持。所有其他作者都没有披露。

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要查看此许可证的副本，请访问http://creativecommons.org/licenses/by-nc-nd/4.0/.

Reprints and permissionsAbout this articleCite this articleDuffin, J., Sayin, E.S., Sobczyk, O. et al. Cerebral perfusion metrics calculated directly from a hypoxia-induced step change in deoxyhemoglobin.

转载和许可本文引用本文Duffin，J.，Sayin，E.S.，Sobczyk，O。等人。直接从缺氧诱导的脱氧血红蛋白阶跃变化计算的脑灌注指标。

Sci Rep 14, 17121 (2024). https://doi.org/10.1038/s41598-024-68047-wDownload citationReceived: 01 October 2023Accepted: 18 July 2024Published: 25 July 2024DOI: https://doi.org/10.1038/s41598-024-68047-wShare this articleAnyone you share the following link with will be able to read this content:Get shareable linkSorry, a shareable link is not currently available for this article.Copy to clipboard.

科学报告1417121（2024）。https://doi.org/10.1038/s41598-024-68047-wDownload引文接收日期：2023年10月1日接收日期：2024年7月18日发布日期：2024年7月25日OI：https://doi.org/10.1038/s41598-024-68047-wShare本文与您共享以下链接的任何人都可以阅读此内容：获取可共享链接对不起，本文目前没有可共享的链接。复制到剪贴板。

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KeywordsCerebrovascularCerebral blood flowMean transit timeCerebral blood volumeMagnetic resonance imagingHypoxiaDeoxyhemoglobin

关键词脑血管脑血流量平均通过时间脑血容量磁共振成像低氧血红蛋白

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