Reliability of Three Dimentional Pseudo-continuous Arterial Spin Labeling:A Volumetric Cerebral Perfusion Imaging with Different Post-labeling Time and Functional State in Health Adults

To evaluate the reliability of three dimensional spiral fast spin echo pseudo-continuous arterial spin labeling(3D pc-ASL)in measuring cerebral blood flow(CBF)with different post-labeling delay time(PLD)in the resting state and the right finger taping state.Methods 3D pc-ASL and three dimensional T1-weighted fast spoiled gradient recalled echo(3D T1-FSPGR)sequence were applied to eight healthy subjects twice at the same time each day for one week interval.ASL data acquisition was performed with post-labeling delay time(PLD)1.5 seconds and 2.0 seconds in the resting state and the right finger taping state respectively.CBF mapping was calculated and CBF value of both the gray matter(GM)and white matter(WM)was automatically extracted.The reliability was evaluated using the intraclass correlation coefficient(ICC)and Bland and Altman plot.Results ICC of the GM(0.84)and WM(0.92)was lower at PLD 1.5 seconds than that(GM,0.88;WM,0.94)at PLD 2.0 seconds in the resting state,and ICC of GM(0.88)was higher in the right finger taping state than that in the resting state at PLD 1.5 seconds.ICC of the GM and WM was 0.71 and 0.78 for PLD 1.5 seconds and PLD 2.0 seconds in the resting state at the first scan,and ICC of the GM and WM was 0.83 and 0.79 at the second scan,respectively.Conclusion This work demonstrated that 3D pc-ASL might be a reliable imaging technique to measure CBF over the whole brain at different PLD in the resting state or controlled state.

Arterial spin labeling in neuroimaging

Arterial spin labeling(ASL) is a magnetic resonance imaging technique for measuring tissue perfusion using a freely diffusible intrinsic tracer.As compared with other perfusion techniques,ASL offers several advantages and is now available for routine clinical practice in many institutions.Its noninvasive nature and ability to quantitatively measure tissue perfusion make ASL ideal for research and clinical studies.Recent technical advances have increased its sensitivity and also extended its potential applications.This review focuses on some basic knowledge of ASL perfusion,emerging techniques and clinical applications in neuroimaging.

Pulsed arterial spin labeling effectively and dynamically observes changes in cerebral blood flow after mild traumatic brain injury

Cerebral blood flow is strongly associated with brain function, and is the main symptom and diagnostic basis for a variety of encephalopathies. However, changes in cerebral blood flow after mild traumatic brain injury remain poorly understood. This study sought to observe changes in cerebral blood flow in different regions after mild traumatic brain injury using pulsed arterial spin labeling. Our results demonstrate maximal cerebral blood flow in gray matter and minimal in the white matter of patients with mild traumatic brain injury. At the acute and subacute stages, cerebral blood flow was reduced in the occipital lobe, parietal lobe, central region, subcutaneous region, and frontal lobe. Cerebral blood flow was restored at the chronic stage. At the acute, subacute, and chronic stages, changes in cerebral blood flow were not apparent in the insula. Cerebral blood flow in the temporal lobe and limbic lobe diminished at the acute and subacute stages, but was restored at the chronic stage. These findings suggest that pulsed arterial spin labeling can precisely measure cerebral blood flow in various brain regions, and may play a reference role in evaluating a patient＇s condition and judging prognosis after traumatic brain injury.

Three-dimensional-arterial spin labeling perfusion correlation with diabetes-associated cognitive dysfunction and vascular endothelial growth factor in type 2 diabetes mellitus rat

BACKGROUND Type 2 diabetes mellitus(T2DM) has been strongly associated with an increased risk of developing cognitive dysfunction and dementia.The mechanisms of diabetes-associated cognitive dysfunction(DACD) have not been fully elucidated to date.Some studies proved lower cerebral blood flow(CBF) in the hippocampus was associated with poor executive function and memory in T2DM.Increasing evidence showed that diabetes leads to abnormal vascular endothelial growth factor(VEGF) expression and CBF changes in humans and animal models.In this study,we hypothesized that DACD was correlated with CBF alteration as measured by three-dimensional(3D) arterial spin labeling(3D-ASL) and VEGF expression in the hippocampus.AIM To assess the correlation between CBF(measured by 3D-ASL and VEGF expression) and DACD in a rat model of T2DM.METHODS Forty Sprague-Dawley male rats were divided into control and T2DM groups.The T2DM group was established by feeding rats a high-fat diet and glucose to induce impaired glucose tolerance and then injecting them with streptozotocin to induce T2DM.Cognitive function was assessed using the Morris water maze experiment.The CBF changes were measured by 3D-ASL magnetic resonance imaging.VEGF expression was determined using immunofluorescence.RESULTS The escape latency time significantly reduced 15 wk after streptozotocin injection in the T2DM group.The total distance traveled was longer in the T2DM group;also,the platform was crossed fewer times.The percentage of distance in the target zone significantly decreased.CBF decreased in the bilateral hippocampus in the T2DM group.No difference was found between the right CBF value and the left CBF value in the T2DM group.The VEGF expression level in the hippocampus was lower in the T2DM group and correlated with the CBF value.The escape latency negatively correlated with the CBF value.The number of rats crossing the platform positively correlated with the CBF value.CONCLUSION Low CBF in the hippocampus and decreased VEGF expression might be crucial in DACD.CBF measured by 3D-ASL might serve as a noninvasive imaging biomarker for cognitive impairment associated with T2DM.

Three-dimensional arterial spin labeling and diffusion kurtosis imaging in evaluating perfusion and infarct area size in acute cerebral ischemia

BACKGROUND Early thrombolytic therapy is crucial to treat acute cerebral infarction,especially since the onset of thrombolytic therapy takes 1-6 h.Therefore,early diagnosis and evaluation of cerebral infarction is important.AIM To investigate the diagnostic value of magnetic resonance multi-delay threedimensional arterial spin labeling(3DASL)and diffusion kurtosis imaging(DKI)in evaluating the perfusion and infarct area size in patients with acute cerebral ischemia.METHODS Eighty-four patients who experienced acute cerebral ischemia from March 2019 to February 2021 were included.All patients in the acute stage underwent magnetic resonance-based examination,and the data were processed by the system’s own software.The apparent diffusion coefficient(ADC),average diffusion coefficient(MD),axial diffusion(AD),radial diffusion(RD),average kurtosis(MK),radial kurtosis(fairly RK),axial kurtosis(AK),and perfusion parameters post-labeling delays(PLD)in the focal area and its corresponding area were compared.The correlation between the lesion area of cerebral infarction under MK and MD and T2-weighted imaging(T2WI)was analyzed.RESULTS The DKI parameters of focal and control areas in the study subjects were compared.The ADC,MD,AD,and RD values in the lesion area were significantly lower than those in the control area.The MK,RK,and AK values in the lesion area were significantly higher than those in the control area.The MK/MD value in the infarct lesions was used to determine the matching situation.MK/MD<5 mm was considered matching and MK/MD≥5 mm was considered mismatching.PLD1.5s and PLD2.5s perfusion parameters in the central,peripheral,and control areas of the infarct lesions in MK/MD-matched and-unmatched patients were not significantly different.PLD1.5s and PLD2.5s perfusion parameter values in the central area of the infarct lesions in MK/MD-matched and-unmatched patients were significantly lower than those in peripheral and control areas.The MK and MD maps showed a lesion area of 20.08±5.74 cm^(2) and 22.09±5.58 cm^(2),respectively.T2WI showed a lesion area of 19.76±5.02 cm^(2).There were no significant differences in the cerebral infarction lesion areas measured using the three methods.MK,MD,and T2WI showed a good correlation.CONCLUSION DKI parameters showed significant difference between the focal and control areas in patients with acute ischemic cerebral infarction.3DASL can effectively determine the changes in perfusion levels in the lesion area.There was a high correlation between the area of the infarct lesions diagnosed by DKI and T2WI.

Neural plasticity secondary to carpal tunnel syndrome: a pseudo-continuous arterial spin labeling study

Conventional neuroimaging techniques cannot truly reflect the change of regional cerebral blood flow in patients with carpal tunnel syndrome.Pseudo-continuous arterial spinning labeling(pCASL)as an efficient non-invasive neuroimaging technique can be applied to directly quantify the neuronal activities of individual brain regions that show the persistent symptoms owing to its better spatial resolution and increased signal-to-noise ratio.Therefore,this prospective observational study was conducted in 27 eligible female carpal tunnel syndrome,aged 57.7±6.51 years.Psychometric tests,nerve conduction studies and pCASL neuroimaging assessment were performed.The results showed that the relevant activated brain regions in the cortical,subcrotical,and cerebral regions were correlated with numbness,pain,functionality,median nerve status and motor amplitude of median nerve(K=21–2849,r=–0.77–0.76,P<0.05).There was a tendency of pain processing which shifted from the nociceptive circuitry to the emotional and cognitive one during the process of chronic pain caused by carpal tunnel syndrome.It suggests the necessity of addressing the ignored cognitive or emotional state when managing patients with carpal tunnel syndrome.Approval for this study was obtained from the Institutional Review Board of The University of Hong Kong/Hospital Authority Hong Kong West,China(HKU/HA HKW IRB,approval No.UW17-129)on April 11,2017.This study was registered in Clinical Trial Registry of The University of Hong Kong,China(registration number:HKUCTR-2220)on April 24,2017.

Intracranial Dural Arteriovenous Fistula: Preliminary Report of Arterial Spin Labeling

Purpose: We report the results of applying arterial spin labeling (ASL) to intracranial dural arteriovenous fistula (DAVF). Methods: Sixteen patients with angiographically confirmed DAVF underwent ASL on a clinical 1.5 T or 3 T MR system. ASL was performed by Q2TIPS (second version of quantitative imaging of perfusion by using a single subtraction MRI pulse sequence with thin-slice TI1 periodic saturation) with echo-planar imaging. Draining veins such as dural venous sinus and cortical veins were evaluated on ASL. Results: ASL clearly depicted draining dural venous sinus in all patients with DAVF Borden type I (6/6, 100%) and type II (4/4, 100%). ASL depicted cortical venous reflux in only one patient with DAVF Borden type II (1/4, 25%). ASL depicted drainage directly into cortical veins in all patients with Borden type III (6/6, 100%). Conclusion: Our preliminary study suggests that ASL can depict draining veins in patients with DAVF.

Hyperperfusion of Multiple Sclerosis Plaques Characterized by 3D FSE Arterial Spin Labelling

MULTIPLE sclerosis(MS)is a common inflammatory demyelinating disorder of central nervous system,and the disease burder could be well evaluated by conventional magnetic resonance imaging(MRI),1 including T2-weighted,fluid-attenuatd inversion recovery,and postcontrast T1-weighted sequences.2 We

Advances in arterial spin labeled cerebral perfusion imaging in cerebrovascular diseases

Cerebrovascular disease is a disease with high morbidity,disability and mortality rates,which seri-ously affects the daily life of patients and is a heavy burden on families and society.Arterial spin labeling(ASL)is a magnetic resonance imaging(MRI)technology that uses the magnetic labeling of hydrogen atoms in arterial blood as tracers to noninvasively evaluate brain blood flow.ASL does not require injection of an exogenous contrast agent,and has the advantages of no radiation,simplicity and low cost.In cerebrovascular diseases,ASL can evaluate the collateral cerebrovascular circulation and abnormal perfusion of brain tissue,which can provide a reliable basis for early diagnosis and clinical decision-making.This study reviewed ASL and its application in the diagnosis,treatment and prognosis of cerebrovascular diseases.

难治性癫痫患者海马灌注的3D-ASL成像评估

目的探讨难治性癫痫患者采用磁共振动脉自旋标记(ASL)技术评估海马灌注情况的价值。方法筛选2019-11-2021-11郴州市第一人民医院的105例受试者,均行海马3D-ASL检查,分为3组(单侧颞叶异常放电组、单侧海马硬化组、健康对照组),分析海马脑血流量(CBF)值与难治性颞叶癫痫的关系。结果健康对照组、单侧颞叶异常放电组患侧与健侧海马、单侧海马硬化组患侧与健侧海马的CBF值分别为(52.13±0.95)mL/(100 g·min)、(49.03±5.28)mL/(100 g·min)、(54.97±1.63)mL/(100 g·min)、(39.41±2.01)mL/(100 g·min)、(48.03±1.69)mL/(100 g·min),除健康对照组与单侧颞叶异常放电组健侧、单侧颞叶异常放电组健侧与单侧海马硬化组健侧比较无统计学差异外,其余组间比较差异均有统计学意义(P<0.00625)。对比健康对照组与单侧颞叶异常放电组患侧得出cut-off值,ROC曲线的最佳临界点为45.81。结论ASL技术在全身及系统性疾病中有一定的诊断价值,难治性颞叶癫痫患者的海马灌注量变化相较于影像学改变更早,有利于临床早期诊断和治疗。

基于TASL的急性前循环缺血性脑卒中药物治疗预后因素分析

目的探讨基于血管选择性动脉自旋标记(territorial arterial spin labeling,TASL)技术的急性前循环缺血性脑卒中(acute anterior circulation ischemic stroke,AACIS)药物治疗预后因素的影响性分析。材料与方法回顾性连续纳入确诊AACIS患者136例并根据其治疗后90 d的预后情况分为预后良好(70例)与预后不良(66例)两组。记录责任血管狭窄度、疗前选择性脑血流量(territorial cerebral blood flow,TCBF)、疗后TCBF_(10 d)、相对选择性脑血流量(relative CBF,rTCBF)以及病灶体积,同时收集患者的基线美国国立卫生研究院卒中量表评分(National Institute of Health Stroke Scale,NIHSS)、卒中分型、年龄、性别、身体质量指数等风险因素信息,将上述指标纳入统计模型。对两组间的计量资料使用Mann-Whitney U检验、计数资料使用χ^(2)检验统计其单因素差异性,对具有统计学意义的指标进行多因素联合logisitic回归分析,使用受试者工作特性曲线(receiver operating characteristic curve,ROC)对结果进行诊断效能评判。结果单因素分析中,年龄(Z=16.022)、基线NIHSS评分(Z=148.400)、卒中分型(Z=49.640)、责任血管狭窄度(Z=27.193)、TCBF_(疗前)(Z=693.000)、rTCBF(Z=18.874)及病灶体积(Z=-10.140)差异均有统计学意义(P<0.05)。多因素联合分析中,年龄(OR=0.108)、基线NIHSS评分(OR=0.615)、卒中分型中的穿支动脉疾病(OR=90.154)、TCBF_(疗前)(OR=4.611)及病灶体积(OR=0.138)对预后具有显著影响(P<0.05),且5者联合对预后预测的判定方法切实有效(P<0.05),ROC曲线下面积为0.962,具有较高价值。责任血管灌注的改变对预后无显著影响(P>0.05)。结论在药物保守治疗方法下,患者90 d预后更易受到年龄、基线NIHSS评分、卒中种类、CBF_(疗前)及病灶体积的影响,并不依赖于责任血管的灌注改善情况。

APT成像与3D-ASL成像在脑膜瘤分型中的鉴别价值

目的 探讨酰胺质子转移成像(APT)与三维动脉自旋标记(3D-ASL)在脑膜瘤术前分型中的鉴别价值。方法 选取25例经病理确诊的脑膜瘤患者,术前行3D-ASL、APT及常规MRI检查,分析不同分型脑膜瘤的常规MRI表现,计算并比较各组间脑膜瘤的肿瘤区域血流量(TBF)、相对脑血流量(rCBF)、肿瘤区域APT值、对侧相应位置CBF对侧值、APT对侧值。结果 纤维型脑膜瘤TBF、rCBF值低于内皮型脑膜瘤、过渡型脑膜瘤,且差异均有统计学意义(P=0.009、0.013<0.05);内皮型脑膜瘤与过渡型脑膜瘤之间差异不显著。纤维型脑膜瘤APT值与内皮型脑膜瘤差异具有统计学意义(P=0.040<0.05)。过渡型及内皮型脑膜瘤MRI平扫信号有其特点。结论 APT成像与3D-ASL成像有利于术前鉴别纤维型、内皮型及过渡型脑膜瘤。

基于压缩感知EPI的ASL技术在健康志愿者脑灌注成像中的应用研究

目的探讨基于联合压缩感知(Compressed Sensing,CS)平面回波成像(Echo Planer Imaging,EPI)的动脉自旋标记(Arterial Spin Labeling,ASL)技术,即EPICS-ASL序列在脑灌注成像中的应用价值,并与传统EPI-ASL序列进行比较。方法前瞻性收集30例志愿者行EPICS-ASL和传统EPI-ASL序列扫描。在ASL原始图上选取基底节、灰质、白质、脑干和小脑作为感兴趣区(Region of Interest,ROI),测量并计算各ROI的信噪比(Signal to Noise Ratio,SNR)和灰质/白质对比噪声比(Contrast to Noise Ratio,CNR灰质/白质);2名医师独立双盲采用4分法主观评估两组图像质量。采用配对t检验比较两组图像的SNR和CNR灰质/白质,采用秩和检验比较两组图像主观评分结果。结果客观评价,EPICS-ASL组各ROI的SNR和CNR灰质/白质均优于EPI-ASL组各ROI的SNR和CNR灰质/白质(均P<0.001);主观评价,EPICS-ASL组的图像质量评分也优于EPI-ASL组(均P<0.001)。结论EPICS-ASL序列显著优于传统EPI-ASL序列的图像SNR和CNR,图像质量更高,具有进一步临床应用的潜力。

3D-ASL对舌肿物的诊断价值及与病理学特征的相关性分析

目的 :探讨3D动脉自旋标记灌注成像技术(3D arterial spin labeling,3D-ASL)、肿瘤血流(tumor blood flow,TBF)与舌部肿物组织病理学特征之间的相关性。方法:前瞻性分析2019年12月—2021年12月上海交通大学医学院附属第九人民医院临床拟诊为舌部肿物的患者55例,术前均行颌面部常规MRI平扫、3D-ASL、扩散加权成像(diffusion-weighted imaging,DWI)和动态增强(dynamic contrast-enhanced,DCE)序列扫描。计算病灶的TBF,术后组织切片用CD34及Ki67染色以评估微血管密度(microvessel density,MVD)。利用SPSS 26.0软件中的Mann-Whitney U检验分析不同疾病间的TBF,以及TBF和MVD的相关性。结果:舌异位甲状腺(ectopic thyroid,ET)在ASL的TBF伪彩图上均表现为整体红色的高灌注区(100%),且高灌注的面积最大(100%)。舌鳞状细胞癌(squamous cell carcinoma,SCC)早期高灌注比例较高(13例,13/15,86.7%)。测量瘤体血流最大区域TBFmax、TBFmean、ADC值之间的差异具有统计学意义(P<0.05)。所有肿瘤中MVD与TBFmean、TBFmax呈强正相关(rs=0.89、0.93,R2=0.70、0.84,P<0.01)。结论:3D-ASL可无创评估舌部肿瘤血流,利于区别良、恶性肿瘤。SCC分级越高,高灌注出现越少,可反映出受肿瘤侵犯的程度。

3D-ASL的rCBF max值在儿童后颅窝肿瘤鉴别诊断中的价值

目的:探讨三维动脉自旋标记成像(3D-ASL)参数rCBF_(max)对儿童后颅窝肿瘤的诊断价值。方法:回顾性分析2018年1月-2022年12月在本院经手术病理证实的52例后颅窝肿瘤患儿的临床和术前MRI资料(平扫、增强和3D-ASL)。其中,髓母细胞瘤28例,毛细胞星形细胞瘤11例,室管膜瘤13例。测量肿瘤实性区域的最大脑血流量(CBF_(max))值,并计算最大相对脑血流量(rCBF_(max)=CBF_(max)/CBF_(健侧正常脑灰质))。采用Kruskal-Wallis检验比较3组肿瘤的rCBF_(max)值,采用ROC曲线和约登指数来确定rCBF_(max)鉴别肿瘤病理类型的最佳阈值、敏感度、特异度和曲线下面积(AUC)。结果:室管膜瘤的rCBF_(max)值最高,为1.53(1.27,2.04),毛细胞星形细胞瘤的rCBF_(max)值最低,为0.69(0.56,0.76),髓母细胞瘤的rCBF_(max)值为0.90(0.84,1.00)。三组肿瘤的rCBF_(max)值比较,差异有统计学意义(P<0.001)。ROC曲线分析显示鉴别室管膜瘤与髓母细胞瘤的rCBF_(max)最佳阈值为1.13,相应的诊断敏感度为100%,特异度为82.1%,AUC为90.7%;鉴别髓母细胞瘤与毛细胞星形细胞瘤的rCBF_(max)最佳阈值为0.80,相应的诊断敏感度为85.7%,特异度为100%,AUC为97.1%。结论:3D-ASL定量参数rCBF_(max)对常见儿童后颅窝肿瘤的鉴别诊断具有较高的临床应用价值。

3D-ASL对急性缺血性脑卒中保守治疗远期预后的预测价值

目的研究动脉自旋标记(arterial spin labeling,ASL)对于急性缺血性脑卒中(acute ischemic stroke,AIS)预后的临床实用价值。方法招募河北医科大学第一医院诊断为AIS患者,计算相对脑血流量(relativa cerebral blood flow,rCBF)。于起病3个月后,对患者进行电话随访,依照改良Rankins评分量表(modified Rankin Scale,mRS)进行预后评估,定义mRS评分0~2分者预后良好,3~6分者预后不良。比较2组间临床基线资料、灌注水平的差异。通过二元Logistic分析急性缺血性脑卒中患者不良预后的相关征象。描绘ROC曲线分析不同灌注水平对预后的预测价值,并计算最佳截断点。结果共纳入36例AIS患者,预后良好组20例,预后不良组16例。临床及影像资料单因素分析显示,入院NIHSS评分、灌注水平对AIS预后存在统计学差异。二元Logistic分析表明低灌注(OR=0.149,95%CI:0.030~0.743,P=0.020)是AIS预后不良的独立危险因素。通过rCBF值预测脑卒中预后的ROC曲线下面积为0.7266(P=0.0210;95%CI:0.5270~0.9261),最佳界点为61.50%,敏感性95.00%,特异性62.50%。结论脑卒中患者急性期ASL可有效预测保守治疗后远期预后,当梗死区域正常灌注,倾向于预后良好,低灌注者往往预后不良,而梗死区域出现高灌注与临床预后无明显相关性。

3D-ASL技术在高级别脑胶质瘤术后复发的价值研究

目的探讨三维动脉自旋标记灌注成像(3D-ASL)在高级别脑胶质瘤术后肿瘤复发的应用价值。方法回顾性分析2019年12月—2021年12月河北省涿州市医院经穿刺活检或手术病理证实的31例高级别脑胶质瘤术后复发患者作为研究对象。全部患者行磁共振平扫、增强扫描、3D-ASL检查,测量高级别脑胶质瘤术后复发区域、对侧正常脑组织脑血流量(CBF),分为复发组CBF、正常组CBF,进行统计学分析。通过常规磁共振检查阅片与常规磁共振检查联合3D-ASL阅片分别诊断,分析诊断符合率进行统计学比较。结果高级别脑胶质瘤术后复发组CBF明显高于正常组CBF,差异有统计学意义(P<0.05);常规磁共振检查联合3D-ASL阅片诊断高级别脑胶质瘤术后复发的诊断符合率较常规磁共振检查阅片显著提高,差异有统计学意义(P<0.05)。结论3D-ASL技术在高级别脑胶质瘤术后复发中有较高的诊断效能,具有重要的临床应用价值。

3D-pCASL评估单侧大脑中动脉慢性重度狭窄患者脑血流动力学可行性研究

目的 探讨3D-pCASL评估单侧大脑中动脉重度狭窄患者脑血流动力学改变的可行性。方法收集CTA或M R A检查提示一侧大脑中动脉重度狭窄(血管腔狭窄70%-99%)患者32例,分别行3D-pCASL(PLD选择1.5s、2.5s)及DSC-PWI检查;在患侧DSC-达峰时间(TTP)异常最显著层面及镜面对照区分别测量两个PLD脑血流量(CBF)及DSC-PWI的CBF、脑血容量(CBV)、平均通过时间(MTT)和TTP,采用配对t检验比较两侧脑区各参数的差异。计算血管狭窄侧与镜面对照脑区相对值,采用Pearson相关检验分析各参数间相关性。同时测量AS L-PLD 1.5s CBF和DSC-TTP灌注异常区域的面积并行配对t检验。结果与对照脑区比较,32例患者异常灌注脑区ASL-PLD 1.5s及2.5s CBF、DSC-CBF、 DSC-MTT、DSC-TTP参数值间差异具有统计学意义(t值分别为-29.94、-20.07、-11.83、14.33、13.48,P值均<0.01);DSC-CBV间无统计学意义(t=-1.51,P=0.143);异常灌注脑区ASL-PLD 1.5s CBF与ASL-PLD 2.5s CBF间差异具有统计学意义(t=5.84,P<0.01)。标准化后ASLPLD 1.5s rCBF与DSC-rMTT、DSC-rTTP呈负相关(r值分别为-0.71、-0.79,P值均<0.01),ASL-PLD2.5s rCBF与DSC-rC BF差异无统计学意义(t=-1.85,P>0.05)。DSC-TTP与ASL-PLD 1.5s CBF灌注减低区域面积差异无统计学意义(t=1.834,P>0.05)。结论3D-pCASL(PLD 1.5s及2.5s)灌注成像可以评价单侧大脑中动脉重度狭窄患者脑血流动力学的改变情况,并且具有定量及无需注射钆对比剂的优点。

ASL联合SWI在亚急性缺血性脑卒中出血转化及预后评估中的应用

目的:采用动脉自旋标记(ASL)和磁敏感加权成像(SWI)观察亚急性缺血性脑卒中梗死区高灌注与出血转化(HT)的相关性以及对90天预后的影响。方法:纳入95例亚急性缺血性卒中患者,入院后采用抗血小板聚集药物(单抗或双抗)治疗,于症状发作后3~7天内行多序列MRI检查(T_(1)WI、T_(2)WI、DWI、MRA、ASL、SWI)。收集和评估临床因素,包括人口统计学、危险因素、卒中特征等。根据ASL梗死区灌注情况分为高灌注和非高灌注,高灌注定义为梗死区脑血流量增加≥对侧的130%。根据SWI序列评估梗死区有无HT,并进一步将HT分为出血性梗死(HI)及脑实质出血(PH)。预后良好定义为90天改良Rankin量表(mRS)评分0~2分。采用独立样本t检验、Mann-Whitney U检验、χ^(2)检验或Fisher确切概率法比较HT组和无HT组各临床因素及影像特征的差异,二元Logistic回归分析明确影响HT的独立因素,进一步探讨梗死区高灌注与HT及90天临床结局的相关性。结果:HT组40例,无HT组55例,HT组患者的入院NIHSS评分更高、梗死体积更大、梗死区高灌注比例更多(P均<0.05)。梗死区高灌注是HT发生的独立危险因素(OR=8.162,P=0.001),但80%的HT表现为HI。90天预后良好组57例,预后不良组38例,预后良好组患者的入院及出院NIHSS评分更低、梗死体积更小、梗死区高灌注比例更多(P均<0.05),而HT在两组间差异无统计学意义(P>0.05)。结论:亚急性期缺血性卒中梗死区高灌注与患者90天良好预后相关,但同时高灌注是HT发生的独立危险因素,虽然大部分表现为HI,临床仍需严格管理血压,以减少PH的发生。

定量脑电图联合ASL灌注成像在单侧大脑中动脉狭窄患者中的评估

目的 分析定量脑电图(quantitative electroencephalogram, qEEG)联合磁共振动脉自旋标记(arterial spin labeling, ASL)灌注成像对单侧大脑中动脉(middle cerebral artery stenosis, MCA)狭窄的评估价值。方法 纳入单侧MCA狭窄患者82例作为研究对象,所有患者均行qEEG、ASL灌注成像及CT脑血管造影(CT angiography, CTA)检查,根据CTA检查结果将患者分为轻度狭窄组、中度狭窄组和重度狭窄组,比较3组患者qEEG与ASL灌注成像参数[慢波化指数(delta and theta/alpha+beta ratio, DTABR)、脑电时间对称指数(temporal brain symmetry index, tBSI)、脑电图空间对称指数(spatial brain symmetry index, sBSI)、脑血流量值(cerebral blood flow, CBF)],分析qEEG联合ASL灌注成像对单侧MCA狭窄的评估价值。结果 82例单侧MCA狭窄患者经CTA检查显示,轻度狭窄28例、中度狭窄32例、重度狭窄22例。中度狭窄组和重度狭窄组sBSI、tBSI值高于轻度狭窄组,重度狭窄组sBSI、tBSI值高于中度狭窄组(P<0.05);中度狭窄组和重度狭窄组患侧CBF值、患侧与健侧CBF比值、MoCA及MMSE评分低于轻度狭窄组,重度狭窄组低于中度狭窄组(P<0.05);绘制受试者工作特征(receiver operating cure, ROC)曲线,结果显示sBSI、tBSI、患侧CBF、患侧与健侧CBF比值单独及联合评估轻中度及中重度MCA狭窄的AUC均>0.7,具有中等评估价值,联合评估价值最佳。结论 qEEG联合ASL灌注成像对单侧MCA狭窄具有较高的评估价值,可准确反映MCA狭窄程度。