64层螺旋CT血管成像诊断胚胎型大脑后动脉及与DSA诊断的比较研究

目的:探讨64层螺旋CT血管成像(CTA)诊断胚胎型大脑后动脉(FTF)的准确性及其临床价值.方法:回顾性分析62例同时做了64层螺旋CTA和DSA脑血管检查患者的影像学资料,将CTA诊断FTP的结果与DSA检查结果进行比较,分析CTA诊断FTP的准确性.结果:62例中,DSA诊断FTP10例,CTA诊断FTP13例,CTA诊断FTP的敏感性为100%,特异性为96.40%,准确性为96.77%.经Kappa一致性检验,CTA与DSA诊断FTA的结果高度一致(P<0.001).结论:64层螺旋CTA能够无创性准确判断FTP的存在,对筛选FTP患者具有重要意义,能为脑血管疾病的诊断与治疗提供重要信息.     

老年脑梗死患者急性期全脑血管造影及脑动脉狭窄的危险因素分析

目的:探究老年脑梗死患者急性期全脑血管造影(DSA)及脑动脉狭窄的危险因素。方法:选择2010年1月~2016年9月期间我院收治的562例老年脑卒中患者为研究对象。经DSA造影观察脑血管动脉造影脉狭窄情况,并收集患者一般资料,采用单因素分析及多因素logistics回归分析脑动脉狭窄的危险因素。结果:562例脑卒中患者经DSA检查共发现469例患者出现脑动脉狭窄,中度狭窄301例,血管重度狭窄168例;颅内段发生率显著高于颅外段(P0.05);高龄(OR=1.434,P0.05)、高血压(OR=2.084,P0.05)、糖尿病(OR=2.235,P0.05)及吸烟(OR=2.734,P0.05)是老年脑卒中患者脑血管狭窄的危险因素。结论:DSA显示老年人脑卒中患者多存在脑血管动脉狭窄的发生,年龄、高血压、糖尿病及吸烟是老年脑卒中患者脑血管狭窄的危险因素。     

Scan-Rescan Reproducibility of High Resolution Magnetic Resonance Imaging of Atherosclerotic Plaque in the Middle Cerebral Artery

Purpose

To evaluate the scan-rescan reproducibility of high-resolution magnetic resonance imaging (MRI) of middle cerebral artery (MCA) plaque, and calculate the number of subjects needed for future longitudinal clinical studies.

Material and Methods

Twenty two patients with MCA plaque were scanned twice by a T₂-weighted fast-spin-echo sequence at 3T. Areas and volumes of MCA lumen, total vessel and plaque were quantified and compared between two repeated scans. Agreement and measurement error was quantified by intraclass correlation coefficient (ICC) and coefficient of variance (CV) as defined by standard deviation (SD) of pair wise difference / mean. Sample size needed to detect 5% to 20% changes in area/volume was calculated using 80% power and 5% significance level.

Results

There was no significant different between the area and volume measurements of two repeated scans (p>0.05) with good agreement (ICC range 0.97–0.98 for area and 0.99 for volume). Relatively small measurement errors were observed with CVs range 6.1%-11.8% for area quantification and 4.9%-8.0% for volume quantification. Volume measurements tended to have 19.7% to 32.2% smaller CVs compared with area measurements. Sample size calculation showed a group of 47 patients was sufficient to detect 5% to 10% changes in MCA area/volume.

Conclusion

High resolution MRI is feasible for quantifying intracranial plaque area and volume in longitudinal clinical studies with low scan-rescan variability. Volume measurement tends to be more reproducible compared with area measurements.     

Instability of the Middle Cerebral Artery Blood Flow in Response to CO2

Background

The middle cerebral artery supplies long end-artery branches to perfuse the deep white matter and shorter peripheral branches to perfuse cortical and subcortical tissues. A generalized vasodilatory stimulus such as carbon dioxide not only results in an increase in flow to these various tissue beds but also redistribution among them. We employed a fast step increase in carbon dioxide to detect the dynamics of the cerebral blood flow response.

Methodology/Principal Findings

The study was approved by the Research Ethics Board of the University Health Network at the University of Toronto. We used transcranial ultrasound to measure the time course of middle cerebral artery blood flow velocity in 28 healthy adults. Normoxic, isoxic step increases in arterial carbon dioxide tension of 10 mmHg from both hypocapnic and normocapnic baselines were produced using a new prospective targeting system that enabled a more rapid step change than has been previously achievable. In most of the 28 subjects the responses at both carbon dioxide ranges were characterised by more complex responses than a single exponential rise. Most responses were characterised by a fast initial response which then declined rapidly to a nadir, followed by a slower secondary response, with some showing oscillations before stabilising.

Conclusions/Significance

A rapid step increase in carbon dioxide tension is capable of inducing instability in the cerebral blood flow control system. These dynamic aspects of the cerebral blood flow responses to rapid changes in carbon dioxide must be taken into account when using transcranial blood flow velocity in a single artery segment to measure cerebrovascular reactivity.     

CAS和CEA治疗颈内动脉重度狭窄疗效及对脑血流量、血清miR-145、IGF1R的影响

目的:探讨颈动脉支架植入术(CAS)和颈动脉内膜剥脱术(CEA)治疗颈内动脉重度狭窄疗效及对脑血流量、血清miR-145、胰岛素样生长因子1受体(IGF1R)的影响.方法:回顾性分析2018年1月至2019年12月我院收治的100例颈动脉重度狭窄患者的临床资料,按照手术方式不同分为A组和B组,每组50例,A组给予CAS...     

Noninvasive Optical Measurement of Cerebral Blood Flow in Mice Using Molecular Dynamics Analysis of Indocyanine Green

In preclinical studies of ischemic brain disorders, it is crucial to measure cerebral blood flow (CBF); however, this requires radiological techniques with heavy instrumentation or invasive procedures. Here, we propose a noninvasive and easy-to-use optical imaging technique for measuring CBF in experimental small animals. Mice were injected with indocyanine green (ICG) via tail-vein catheterization. Time-series near-infrared fluorescence signals excited by 760 nm light-emitting diodes were imaged overhead by a charge-coupled device coupled with an 830 nm bandpass-filter. We calculated four CBF parameters including arrival time, rising time and mean transit time of a bolus and blood flow index based on time and intensity information of ICG fluorescence dynamics. CBF maps were generated using the parameters to estimate the status of CBF, and they dominantly represented intracerebral blood flows in mice even in the presence of an intact skull and scalp. We demonstrated that this noninvasive optical imaging technique successfully detected reduced local CBF during middle cerebral artery occlusion. We further showed that the proposed method is sufficiently sensitive to detect the differences between CBF status in mice anesthetized with either isoflurane or ketamine–xylazine, and monitor the dynamic changes in CBF after reperfusion during transient middle cerebral artery occlusion. The near-infrared optical imaging of ICG fluorescence combined with a time-series analysis of the molecular dynamics can be a useful noninvasive tool for preclinical studies of brain ischemia.     

磁共振血管成像联合ABCD3-Ⅰ评分对TIA后继发脑梗死风险的预测价值分析

摘要 目的：分析磁共振血管成像（MAR）联合ABCD3-Ⅰ评分对短暂性脑缺血发作（TIA）后继发脑梗死风险的预测价值。方法：选取本院87例TIA患者,均行MAR检查及ABCD3-Ⅰ评分,随访90 d内继发脑梗死情况,分为继发脑梗死组与无脑梗死组,比较2组临床资料、MAR检查结果及ABCD3-Ⅰ评分,采用受试者工作特征曲线（ROC）分析MAR联合ABCD3-Ⅰ评分对脑梗死预测价值。结果：继发脑梗死组与无脑梗死组性别、年龄、BMI、吸烟史、饮酒史、糖尿病、高血压、房颤、高脂血症情况比较无统计学意义（P＞0.05）; 继发脑梗死组中度狭窄与严重狭窄-闭塞占比、ABCD3-Ⅰ评分高危占比高于无脑梗死组（P均＜0.001）;MAR检查、ABCD3-Ⅰ评分及二者联合预测曲线下面积（AUC）分别为0.863、0.827、0.942,联合预测具有较高预测效能,敏感度为100%,特异度为74.2%。结论：MAR联合ABCD3-Ⅰ评分对TIA后继发脑梗死具有较高预测效能,能够用于脑梗死的风险评估。     

Evaluation of Flow Velocity in Unilateral Middle Cerebral Artery Stenosis by Transcranial Doppler

To determine the optimal velocity values in diagnosing unilateral middle cerebral artery (MCA) stenosis by Transcranial Doppler (TCD), and improve the diagnostic accuracy using magnetic resonance angiography (MRA), a total of 302 unilateral MCA stenosis patients undergoing TCD also consented to a MRA of the intracranial arteries. The peak systolic velocity (PSV) and each MCA spectrum for each patient were recorded. Using the MRA to confirm, the degree of middle cerebral artery stenosis was categorized into four groups: normal (normal caliber and signal), mild (<50 %), moderate (50–69 %), severe (70–99 %, or no flow detected). The velocity difference among these four groups was significant (P < 0.001). The optimal PSV values for normal and stenosis were 160 cm/s. For mild and moderate were 200 cm/s, for moderate and severe were 280 cm/s. Using PSV as the diagnostic criteria, the Kappa number was >0.668. The optimal PSV differential value for mild and moderate was 70 cm/s, for moderate and severe at 120 cm/s. Optimal combined criteria for moderate stenosis were PSV >200 cm/s and PSV differential value >70 cm/s (specificity 87.2 %), for severe stenosis were PSV >280 cm/s and PSV differential value >120 cm/s (sensibility 81.6 %). Transcranial Doppler distinguishes normal and MCA stenosis with a reduced lumen diameter of less than 50 %. Using the PSV criteria, TCD has a high coincidence rate with MRA in the diagnosis of MCA stenosis. Combined PSV differential value and the abnormal spectrum may improve the accuracy of TCD in diagnosing moderate or severe stenosis.     

头颅电子计算机断层扫描血管造影和头颅磁共振血管成像在颅内动脉瘤中诊断价值比较的回顾性研究

摘要 目的：研究对比头颅电子计算机断层扫描血管造影（CTA）和头颅磁共振血管成像（MRA）在颅内动脉瘤中诊断价值。方法：回顾性分析医院2019年1月2日～2020年12月15日收治的60例疑似颅内动脉瘤患者资料,所有受试者均开展头颅CTA检查、MRA检查以及数字减影血管造影（DSA）检查。以DSA检查结果为金标准,比较头颅CTA和头颅MRA诊断颅内动脉瘤的效能。此外,对比头颅CTA和头颅MRA诊断不同分级、不同部位颅内动脉瘤的符合率。结果：DAS检查结果显示确诊动脉瘤患者48例,共检出动脉瘤74个,CTA检出动脉瘤65个,MRA检出动脉瘤51个,CTA动脉瘤检出率高于MRA检出率（均P＜0.05）。以DSA结果为金标准,CTA诊断颅内动脉瘤的灵敏度、特异度以及准确度分别为94.20%（65/69）、60.00%（3/5）、91.89%（68/74）,均高于MRA的82.26%（51/62）、41.67%（5/12）、75.68%（56/74）（均P＜0.05）。CTA诊断1级颅内动脉瘤的符合率为13.85%（9/65）,高于MRA的7.84%（4/51）（P＜0.05）。各种检查方式诊断不同部位颅内动脉瘤的符合率对比均无明显差异（均P＞0.05）。结论：CTA诊断颅内动脉瘤的灵敏度、特异度以及准确度均高于MRA,可提高对小直径肿瘤的检出率。然而,MRA具有无辐射、检测费用少、安全性高等优势,临床实际工作中可综合选择合理的检查方式。     

Three-Directional Evaluation of Mitral Flow in the Rat Heart by Phase-Contrast Cardiovascular Magnetic Resonance

Purpose

Determination of mitral flow is an important aspect in assessment of cardiac function. Traditionally, mitral flow is measured by Doppler echocardiography which suffers from several challenges, particularly related to the direction and the spatial inhomogeneity of flow. These challenges are especially prominent in rodents. The purpose of this study was to establish a cardiovascular magnetic resonance (CMR) protocol for evaluation of three-directional mitral flow in a rodent model of cardiac disease.

Materials and Methods

Three-directional mitral flow were evaluated by phase contrast CMR (PC-CMR) in rats with aortic banding (AB) (N = 7) and sham-operated controls (N = 7). Peak mitral flow and deceleration rate from PC-CMR was compared to conventional Doppler echocardiography. The accuracy of PC-CMR was investigated by comparison of spatiotemporally integrated mitral flow with left ventricular stroke volume assessed by cine CMR.

Results

PC-CMR portrayed the spatial distribution of mitral flow and flow direction in the atrioventricular plane throughout diastole. Both PC-CMR and echocardiography demonstrated increased peak mitral flow velocity and higher deceleration rate in AB compared to sham. Comparison with cine CMR revealed that PC-CMR measured mitral flow with excellent accuracy. Echocardiography presented significantly lower values of flow compared to PC-CMR.

Conclusions

For the first time, we show that PC-CMR offers accurate evaluation of three-directional mitral blood flow in rodents. The method successfully detects alterations in the mitral flow pattern in response to cardiac disease and provides novel insight into the characteristics of mitral flow.     

Validation of Perfusion Quantification with 3D Gradient Echo Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using a Blood Pool Contrast Agent in Skeletal Swine Muscle

The purpose of our study was to validate perfusion quantification in a low-perfused tissue by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with shared k-space sampling using a blood pool contrast agent. Perfusion measurements were performed in a total of seven female pigs. An ultrasonic Doppler probe was attached to the right femoral artery to determine total flow in the hind leg musculature. The femoral artery was catheterized for continuous local administration of adenosine to increase blood flow up to four times the baseline level. Three different stable perfusion levels were induced. The MR protocol included a 3D gradient-echo sequence with a temporal resolution of approximately 1.5 seconds. Before each dynamic sequence, static MR images were acquired with flip angles of 5°, 10°, 20°, and 30°. Both static and dynamic images were used to generate relaxation rate and baseline magnetization maps with a flip angle method. 0.1 mL/kg body weight of blood pool contrast medium was injected via a central venous catheter at a flow rate of 5 mL/s. The right hind leg was segmented in 3D into medial, cranial, lateral, and pelvic thigh muscles, lower leg, bones, skin, and fat. The arterial input function (AIF) was measured in the aorta. Perfusion of the different anatomic regions was calculated using a one- and a two-compartment model with delay- and dispersion-corrected AIFs. The F-test for model comparison was used to decide whether to use the results of the one- or two-compartment model fit. Total flow was calculated by integrating volume-weighted perfusion values over the whole measured region. The resulting values of delay, dispersion, blood volume, mean transit time, and flow were all in physiologically and physically reasonable ranges. In 107 of 160 ROIs, the blood signal was separated, using a two-compartment model, into a capillary and an arteriolar signal contribution, decided by the F-test. Overall flow in hind leg muscles, as measured by the ultrasound probe, highly correlated with total flow determined by MRI, R = 0.89 and P = 10⁻⁷. Linear regression yielded a slope of 1.2 and a y-axis intercept of 259 mL/min. The mean total volume of the investigated muscle tissue corresponds to an offset perfusion of 4.7mL/(min ⋅ 100cm³). The DCE-MRI technique presented here uses a blood pool contrast medium in combination with a two-compartment tracer kinetic model and allows absolute quantification of low-perfused non-cerebral organs such as muscles.     

Comparison of an Oscillometric Method with Cardiac Magnetic Resonance for the Analysis of Aortic Pulse Wave Velocity

Objectives

Pulse wave velocity (PWV) is the proposed gold-standard for the assessment of aortic elastic properties. The aim of this study was to compare aortic PWV determined by a recently developed oscillometric device with cardiac magnetic resonance imaging (CMR).

Methods

PWV was assessed in 40 volunteers with two different methods. The oscillometric method (PWV_OSC) is based on a transfer function from the brachial pressure waves determined by oscillometric blood pressure measurements with a common cuff (Mobil-O-Graph, I.E.M. Stolberg, Germany). CMR was used to determine aortic PWV_CMR with the use of the transit time method based on phase-contrast imaging at the level of the ascending and abdominal aorta on a clinical 1.5 Tesla scanner (Siemens, Erlangen, Germany).

Results

The median age of the study population was 34 years (IQR: 24–55 years, 11 females). A very strong correlation was found between PWVOSC and PWVCMR (r = 0.859, p < 0.001). Mean PWV_OSC was 6.7 ± 1.8 m/s and mean PWVCMR was 6.1 ± 1.8 m/s (p < 0.001). Analysis of agreement between the two measurements using Bland-Altman method showed a bias of 0.57 m/s (upper and lower limit of agreement: 2.49 m/s and -1.34 m/s). The corresponding coefficient of variation between both measurements was 15%.

Conclusion

Aortic pulse wave velocity assessed by transformation of the brachial pressure waveform showed an acceptable agreement with the CMR-derived transit time method.     

超声造影对原发性肝癌数字减影血管造影引导下肝动脉化疗栓塞治疗的疗效评估价值

目的:探讨超声造影评估原发性肝癌(HCC)数字减影血管造影(DSA)引导下肝动脉化疗栓塞(TACE)治疗疗效的价值。方法:选择2016年10月至2018年10月我院收治的77例HCC患者,均在DSA引导下行TACE治疗,治疗前后采用超声造影评价疗效。结果:77例HCC患者均顺利完成TACE治疗,治疗后始增强度、增强速率降低(P0.05),始增时间、达峰时间、峰值加速时间增加(P0.05)。治疗后完全缓解(CR)+部分缓解(PR)为有效共46例(有效组),稳定(SD)+进展(PD)为无效共31例(无效组),有效组治疗后始增强度、增强速率低于无效组(P0.05),始增时间、达峰时间、峰值加速时间多于无效组(P0.05)。受试者工作特征曲线(ROC)分析结果显示,始增时间、达峰时间、峰值加速时间、始增强度、增强速率预测HCC患者DSA引导下TACE治疗疗效的曲线下面积(AUC)分别为0.658、0.717、0.64、0.668、0.713。结论:超声造影定量参数在HCC患者DSA引导下TACE治疗前后有着较为明显的变化,其超声参数达峰时间、增强速率对DSA引导下TACE治疗疗效的预测效能较好。     

弥散加权成像联合磁共振波谱分析在脑梗死中的应用研究

目的探讨脑梗死弥散加权成像（DWI）和磁共振波谱分析（MRS）的特点和影响因素,及二者对评估脑梗死的临床价值。方法采用Philips Achieva 1.5T双梯度超导磁共振扫描仪,对72例临床疑是脑梗死患者行常规T1WI、T2WI、FLAIR、DWI、MRS检查,在工作站上测定梗死核心区、内缘区、外缘区、周围区和镜像区的ADC值和代谢物Lac、NAA、Cr、Cho、NAA/Cr、Lac/Cr、Lac/NAA值。结果 DWI显示的梗死灶范围较常规MRI像更加准确、清晰;超急性期、急性期、亚急性期和慢性期梗死核心区的Lac/Cr值和Lac/NAA值高于对侧镜像区,ADC值和NAA/Cr值低于对侧镜像区,存在统计学差异（P〈0.05）;DWI的影响因素有b值、扩散系数、T2穿透效应和各向异性等,MRS的影响因素有磁场均匀性、压水压脂性能、体素、TE与TR、组织代谢物浓度和波谱采集链等。结论 DWI结合MRS能更加全面地评估缺血半暗带,更精确地对脑梗死进行分期和定位。     

Reversible Loss of N-Acetylaspartate After 15-Min Transient Middle Cerebral Artery Occlusion in Rat: A Longitudinal Study with In Vivo Proton Magnetic Resonance Spectroscopy

It is generally accepted that N-acetylaspartate (NAA) can be used a biochemical marker for assessing neuronal viability/integrity after cerebral ischemia. However, this view has recently been questioned based on observations showing that after a photothrombotic permanent ischemia the acute decline of NAA in the infracted regions, where massive neuronal loss persists, is reversible over time. In this study, we measured the longitudinal changes of NAA and total creatine (Cr) in ischemic rat brain after a 15-min transient middle cerebral artery occlusion (MCAO) by in vivo ¹H magnetic resonance spectroscopy. The results showed that the levels of NAA and total Cr in the ischemic lesion decrease significantly at 1 day post-ichemia, followed by spontaneous recovery to the control levels by 2 weeks and remained stable thereafter up to 16 weeks. The normalization of NAA and total Cr levels was associated histologically with persisted neuronal loss up to 90 % in the ischemic core, and accompanied by marked reactive astrocytic responses occurring with a similar time course. The absolute T₂ relaxation time in the ischemic lesion increased during acute phase, and declined afterwards during subacute and chronic phases of 15-min MCAO. The delayed decreases of T₂ in the ischemic lesion might be associated with deposition of paramagnetic species, such as manganese and iron originated from chronic inflammation, vascular degradation and/or hemorrhagic transformation. The results of this study give further support to the hypothesis that the recovery of NAA after cerebral ischemia might have contributions from reactive glia cells, and caution the use of NAA as a specific neuronal marker during the chronic stage of cerebral ischemia.     

调任通督针刺法联合感觉统合训练对注意缺陷多动障碍患儿注意力和脑动脉血流速度的影响

摘要 目的：观察感觉统合训练联合调任通督针刺法对注意缺陷多动障碍（ADHD）患儿注意力和脑动脉血流速度的影响。方法：纳入东莞市中医院2020年1月到2021年1月期间收治的ADHD患儿100例,入组患儿按门诊号单双数分为对照组（单数,感觉统合训练）和研究组（双数,调任通督针刺法联合感觉统合训练）,各为50例,两组患儿均干预3个月。观察并对比两组疗效、中医证候总积分、注意力、脑动脉血流速度、Conners父母评症状量表（PSQ）、联合型瑞文测验 (CRT) 评分。结果：研究组的临床总有效率明显高于对照组（P<0.05）。干预3个月后,两组注意力情况：错误数、漏报数较干预前减少,反应时间较干预前缩短,且研究组的变化程度大于对照组（P<0.05）。研究组患儿干预3个月后双侧中动脉（MCA）、前动脉（ACA）、后动脉（PCA）的血流速度均较干预前增快,且高于同时期的对照组患儿（P＜0.05）。干预3个月后,两组PSQ评分、中医证候总积分下降,CRT评分升高,且研究组的变化程度大于对照组（P<0.05）。结论：调任通督针刺法联合感觉统合训练可有效改善ADHD患儿注意力,促进临床症状改善,调节脑血流速度,临床应用价值较好。     

The Effect of Morphine on Regional Cerebral Blood Flow Measured by 99mTc-ECD SPECT in Dogs

To gain insights into the working mechanism of morphine, regional cerebral blood flow (rCBF) patterns after morphine administration were assessed in dogs. In a randomized cross-over experimental study, rCBF was estimated with ^99mTc-Ethylcysteinate Dimer single photon emission computed tomography in 8 dogs at baseline, at 30 minutes and at 120 minutes after a single bolus of morphine. Perfusion indices (PI) in the frontal, parietal, temporal and occipital cortex and in the subcortical and cerebellar region were calculated. PI was significantly decreased 30 min after morphine compared to baseline in the right frontal cortex. The left parietal cortex and subcortical region showed a significantly increased PI 30 min after morphine compared to baseline. No significant differences were noted for the other regions or at other time points. In conclusion, a single bolus of morphine generated a changing rCBF pattern at different time points.