Magnetic resonance diffusion tensor imaging following major ozonated autohemotherapy for treatment of acute cerebral infarction

Major ozonated autohemotherapy has been shown to promote recovery of upper limb motor function in patients with acute cerebral infarction, but whether naajor ozonated autohelnotherapy affects remote in）ury remains poorly understood. Here, we assumed that major ozonated autohemotherapy contributes to recovery of clinical function, possibly by reducing remote injury after acute cerebral infarction. Sixty acute cerebral infarction patients aged 30-80 years were equally and randomly allocated to ozone treatment and control groups. Patients in the ozone treatment group received medical treatment and major ozonated autohemotherapy （47 mg/L, 100 mL ozone） for 10 ± 2 days. Patients in the control group received medical treatment only. National Institutes of Health Stroke Scale score, modified Rankin scale score, and reduced degree of fractional anisotropy values of brain magnetic resonance diffusion tensor imaging were remarkably decreased, brain function improved, clinical efficiency significantly increased, and no obvious adverse reactions detected in the ozone treatment group compared with the control group. These findings suggest that major ozonated autohemotherapy promotes recovery of neurological function in acute cerebral infarction patients by reducing re,note injury, and additionally, exhibits high safety.

Diffusion-weighted magnetic resonance imaging reflects activation of signal transducer and activator of transcription 3 during focal cerebral ischemia/reperfusion

Signal transducer and activator of transcription（STAT）is a unique protein family that binds to DNA,coupled with tyrosine phosphorylation signaling pathways,acting as a transcriptional regulator to mediate a variety of biological effects.Cerebral ischemia and reperfusion can activate STATs signaling pathway,but no studies have confirmed whether STAT activation can be verified by diffusion-weighted magnetic resonance imaging（DWI）in rats after cerebral ischemia/reperfusion.Here,we established a rat model of focal cerebral ischemia injury using the modified Longa method.DWI revealed hyperintensity in parts of the left hemisphere before reperfusion and a low apparent diffusion coefficient.STAT3 protein expression showed no significant change after reperfusion,but phosphorylated STAT3 expression began to increase after 30 minutes of reperfusion and peaked at 24 hours.Pearson correlation analysis showed that STAT3 activation was correlated positively with the relative apparent diffusion coefficient and negatively with the DWI abnormal signal area.These results indicate that DWI is a reliable representation of the infarct area and reflects STAT phosphorylation in rat brain following focal cerebral ischemia/reperfusion.

Consistency between magnetic resonance diffusion-weighted images and pathological findings in a hyperacute cerebral infarction rabbit model

BACKGROUND： Because magnetic resonance diffusion-weighted imaging is sensitive to water molecule movement, it has particular advantages for early diagnosis of cerebral infarction. However, the relationship between apparent diffusion coefficient changes with ischemia time, particularly relative apparent diffusion coefficient and tissue pathological changes remains controversial. OBJECTIVE： To explore the correlation between apparent diffusion coefficient changes and pathologic changes in hyperacute cerebral infarction. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment of neuroimaging. The study was performed at the Laboratory of Radiology Department, Longgang Central Hospital of Shenzhen from October 2007 to October 2008. MATERIALS： Magnetic resonance scanner was purchased from Philips Medical Systems, Best, the Netherlands. METHODS： A total of 42 healthy, adult, New Zealand rabbits were randomly assigned into sham-operation, ischemia 0.5-, 1-, 2-, 3-, 4-, and 6-hour groups, with six animals in each group. Local cerebral ischemia model was established by right middle cerebral artery occlusion, and cranial MRI scanning and pathologic observation were performed, respectively, at 0.5, 1,2, 3, 4, and 6 hours following ischemia. The middle cerebral artery of sham-operation group was only exposed, but not occluded. Images at the above-mentioned time points were also collected. MAIN OUTCOME MEASURES： Apparent diffusion coefficient and relative apparent diffusion coefficient values of abnormal signal on diffusion-weighted imaging were calculated and compared with pathological changes in the ischemic region. RESULTS： No abnormal diffusion-weighted imaging signals or pathological changes were observed in the sham-operation group. Abnormal signal intensity on diffusion-weighted imaging was first observed in the 0.5-hour group. Apparent diffusion coefficient and relative apparent diffusion coefficient values decreased in all middle cerebral artery occlusion rabbits and reached lowest levels at 3 hours, followed by a gradual increase. The right ischemic basal ganglia region with high signal intensity on diffusion-weighted imaging extended with increasing time of occlusion, and the pathologic outcome corresponded with MRI changes. CONCLUSION： Relative apparent diffusion coefficient values changed regularly with ischemia time and displayed good correspondence to pathological manifestations.

Magnetic resonance perfusion imaging evaluation in perfusion abnormalities of the cerebellum after supratentorial unilateral hyperacute cerebral infarction

Magnetic resonance imaging （MRI） data of 10 patients with hyperacute cerebral infarction （≤6 hours） were retrospectively analyzed.Six patients exhibited perfusion defects on negative enhancement integral maps,four patients exhibited perfusion differences in pseudo-color on mean time to enhance maps,and three patients exhibited perfusion differences in pseudo-color on time to minimum maps.Dynamic susceptibility contrast-enhanced perfusion weighted imaging revealed a significant increase in region negative enhancement integral in the affected hemisphere of patients with cerebral infarction.The results suggest that dynamic susceptibility contrast-enhanced perfusion weighted imaging can clearly detect perfusion abnormalities in the cerebellum after unilateral hyperacute cerebral infarction.

Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging

Some in vitro experiments have shown that erythropoietin （EPO） increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging （PWI） and diffusion-weighted imaging （DWI） have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO （5,000 U/kg） 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling （TUNEL） were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

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.

An Early Continuous Experimental Study on Magnetic Resonance Diffusion-weighted Image of Focal Cerebral Ischemia and Reperfusion in Rats

Summary： The chronological and spatial rules of changes during focal cerebral ischemia and reperfusion in different brain regions with magnetic resonance diffusion-weighted imaging （DWI） in a model of occlusion of middle cerebral artery （MCAO） and the development of cytotoxic edema in acute phase were explored. Fifteen healthy S-D rats with MCA occluded by thread-emboli were randomly divided into three groups. 15 min after the operation, the serial imaging was scanned on DWI for the three groups. The relative mean signal intensity （RMSI） of the frontal lobe, parietal lobe, lateral cauda-putamen, medial cauda-putamen and the volume of regions of hyperintense signal on DWI were calculated. After the last DWI scanning, T2WI was performed for the three groups. After 15 rain ischemia, the rats was presented hyperintense signals on DWI. The regions of hyperintense signal were enlarged with prolonging ischemia time. The regions of hyperintense signal were back to normal after 60 min reperfusion with a small part remaining to show hyperintense signal. The RMSIs of parietal lobe and lateral cauda-putamen were higher than that of the frontal lobe and medial cauda-putamen both in ischemia phase and recanalization phase. The three groups were normal on T2WI imaging. DWI had good sensitivity to acute cerebral ischemia, which was used to study the chronological and spatial rules of development of early cell edema in ischemia regions.

Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations

The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China(approval No. 2014002).Diffusion kurtosis imaging(DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke(61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter(n = 52), corpus callosum(n = 14), cerebellum(n = 29), basal ganglia and thalamus(n = 21), brainstem(n = 21) and gray-white matter junctions(n = 62). Percentage changes of apparent diffusion coefficient(ΔADC) and DKI-derived indices(fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD_a], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔK_a], and radial kurtosis [ΔK_r]) of each lesion were computed relative to the normal contralateral region. The results showed that(1) there was no significant difference in ΔADC, ΔMD, ΔD_a or ΔD_r among almost all locations.(2) There was significant difference in ΔMK among almost all locations(except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions.(3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups.

Apparent diffusion coefficient evaluation for secondary changes in the cerebellum of rats after middle cerebral artery occlusion

Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the cerebellum, which may be relevant to diaschisis. This phenomenon is often analyzed using positron emission tomography and single photon emission CT. However, these methods are expensive and radioactive. Thus, the present study quantified the changes of infarction core and remote regions after unilateral middle cerebral artery occlusion using apparent diffusion coefficient values. Diffu- sion-weighted imaging showed that the area of infarction core gradually increased to involve the cerebral cortex with increasing infarction time. Diffusion weighted imaging signals were initially in- creased and then stabilized by 24 hours. With increasing infarction time, the apparent diffusion co- efficient value in the infarction core and remote bilateral cerebellum both gradually decreased, and then slightly increased 3-24 hours after infarction. Apparent diffusion coefficient values at remote regions （cerebellum） varied along with the change of supratentorial infarction core, suggesting that the phenomenon of diaschisis existed at the remote regions. Thus, apparent diffusion coefficient values and diffusion weighted imaging can be used to detect early diaschisis.

Aquaporin-4 gene silencing protects injured neurons after early cerebral infarction

Aquaporin-4 regulates water molecule channels and is important in tissue regulation and water transportation in the brain. Upregulation of aquaporin-4 expression is closely related to cellular edema after early cerebral infarction. Cellular edema and aquaporin-4 expression can be determined by measuring cerebral infarct area and apparent diffusion coefficient using diffusion-weighted imaging（DWI）. We examined the effects of silencing aquaporin-4 on cerebral infarction. Rat models of cerebral infarction were established by occlusion of the right middle cerebral artery and si RNA-aquaporin-4 was immediately injected via the right basal ganglia. In control animals, the area of high signal intensity and relative apparent diffusion coefficient value on T2-weighted imaging（T2WI） and DWI gradually increased within 0.5–6 hours after cerebral infarction. After aquaporin-4 gene silencing, the area of high signal intensity on T2 WI and DWI reduced, relative apparent diffusion coefficient value was increased, and cellular edema was obviously alleviated. At 6 hours after cerebral infarction, the apparent diffusion coefficient value was similar between treatment and model groups, but angioedema was still obvious in the treatment group. These results indicate that aquaporin-4 gene silencing can effectively relieve cellular edema after early cerebral infarction; and when conducted accurately and on time, the diffusion coefficient value and the area of high signal intensity on T2 WI and DWI can reflect therapeutic effects of aquaporin-4 gene silencing on cellular edema.

FLAIR高信号血管征-DWI不匹配评估急性脑梗死患者血栓切除术后的预后价值

目的 探讨急性脑梗死患者的FLAIR图像上出现高信号血管征的范围与弥散加权成像范围的不匹配评估患者行血管内血栓切除术(EVT)后功能结局的预后价值。方法回顾性分析60例急性脑梗死发作后行血管内血栓切除术的患者,收集这些患者的FLAIR、DWI、FLAIR高信号血管征与DWI高信号不匹配、功能结果(mRS)以及其他临床相关数据,采用多元Logistic回归分析预测功能结果。结果功能结果良好组(36/60;60.0%)较功能结果不良组(24/60;40.0%)的FVHS-DW I不匹配高(85.29%对45.83%;t=12.371;P<0.001)。多变量Logistic回归分析表明,FVHS-DWI不匹配与良好的功能结局独立相关[OR (95%CI):0.179(0.042~0.494),P<0.001]。结论急性脑梗死患者EVT术前使用FVHS-DWI不匹配评估有助于预测急性脑梗死患者的功能结果。

MRI在急性脑梗死患者血管内血栓切除术后颅内出血的预测价值

目的探讨MRI在急性脑梗死患者进行血管内血栓切除术(EVT)后颅内出血(ICH)的预测价值。方法回顾性分析接受EVT治疗的急性脑梗死患者67例,收集这些患者的弥散加权成像(DWI)、灌注加权成像(PWI)和DWI-PWI不匹配(DPM)的体积以及其他临床相关数据,ICH由非增强CT评估。采用多元logistic回归分析预测急性脑梗死患者治疗后的ICH。结果接受EVT后,ICH的患者空腹血糖[(11.96±1.93)mg/L与(13.26±1.73)mg/L]、HbA1c[(5.73±0.42)%与(6.21±0.49)%]、DWI梗死体积(51.23±41.32 ml与29.61±32.26ml)显著大于无ICH的患者(t=-7.693,P<0.001;t=6.135,P<0.001;t=-2.531,P=0.016)。多变量逻辑回归分析显示血糖[OR(95%CI):1.312(1.145~1.417),P<0.001]、HbA1c[OR(95%CI):38.847(7.216~201.753),P<0.001]以及DWI梗死体积[OR(95%CI):1.021(1.004~1.034),P=0.016]为预测急性脑梗死患者EVT术后ICH独立的预测因子。结论急性脑梗死患者行EVT治疗后,通过检测患者的空腹血糖、HbA1c和DWI梗死体积能够预测ICH的发生风险,从而对后续的临床治疗提供信息。

FVH-DWI不匹配联合血清IL-6、miR-155对进展性脑梗死的预测价值

目的探讨液体衰减反转恢复(FLAIR)序列血管高信号(FVH)-扩散加权成像(DWI)不匹配联合血清白细胞介素(IL)-6、miR-155对进展性脑梗死(PCI)的预测价值。方法选取105例已确诊的脑梗死患者,将其中35例作为PCI组,70例未发生PCI(NPCI)作为NPCI组,均于入院第1天采用酶联免疫吸附法、实时荧光定量聚合酶链反应测定血清IL-6、miR-155表达水平,并行MRI检查,统计FVH-DWI不匹配情况。绘制受试者工作特征(ROC)曲线分析上述指标对PCI的预测价值。结果PCI组FVH-DWI不匹配比例显著小于NPCI组(25.71%vs 58.57%),差异有统计学意义(P<0.05)。PCI组入院第1天血清IL-6水平(121.77±30.34)ng/L、miR-155表达水平(2.07±0.56)均显著高于NPCI组的(81.27±15.09)ng/L、(1.51±0.56),差异有统计学意义(P<0.05)。FVH-DWI不匹配与NIHSS评分呈负相关(P<0.05),血清IL-6、miR-155表达水平与NIHSS评分均呈正相关(P<0.05)。FVH-DWI不匹配联合血清IL-6、miR-155预测PCI的曲线下面积(AUC)为0.919,敏感度、特异度分别为74.29%、97.14%。结论FVH-DWI不匹配联合血清IL-6、miR-155检测对PCI有较高的预测价值。

多模态磁共振成像联合estroke人工智能评估在晚时间窗急性脑梗死动脉取栓术的临床研究

目的分析多模态磁共振成像(MRI)联合estroke人工智能评估在晚时间窗急性脑梗死(AIS)动脉取栓术中的临床价值。方法选取2021年7月至2023年6月本院收治的104例晚时间窗AIS患者,所有患者经多模态MRI联合estroke人工智能评估后均可进行动脉取栓,根据eStroke人工智评估结果,将患者按照梗死体积分为低梗死组(梗死体积<21ml)、中等梗死组(21mL<梗死体积<31mL)及较大梗死组(31mL<梗死体积<51mL)。另同期选取于本院进行急诊取栓的时间窗内AIS患者30例,纳入对照组。术后采用改良脑梗死溶栓(mTICI)分级评估血管再通情况。统计患者取栓次数、下床活动时间及住院时间,统计患者住院期间并发症发生率。出院后所有患者均随访3个月,统计患者90 d死亡情况及脑卒中再发情况。采用改良Rankin量表(mRS)及美国国立卫生院神经功能缺损评分(NIHSS)评估患者神经功能预后。结果与低梗死组比,较大梗死组血管再通率降低(P<0.05),与较大梗死组比较,对照组血管再通率升高(P<0.05);与低梗死组比较,对照组血取栓次数增加(P<0.05);与低梗死组比较,对照组并发症发生率升高(P<0.05);与术前比较,4组患者术后3个月mRS评分、NIHSS评分均降低(P<0.05);与低梗死组比较,中等梗死组及较大梗死组mRS评分、NIHSS评分升高(P<0.05),与中等梗死组比较,较大梗死组mRS评分、NIHSS评分升高(P<0.05),与较大梗死组比较,对照组mRS评分、NIHSS评分降低(P<0.05),低梗死组与对照组比较,mRS评分、NIHSS评分差异无统计学意义(P>0.05)。结论多模态MRI联合estroke人工智能评估晚时间窗AIS动脉取栓术中具有良好的血管再通率,有利于减少取栓次级术后并发症的发生,对于神经功能改善具有积极作用。

磁共振弥散加权成像联合CRP对急性缺血性脑梗死时间窗的鉴别价值

目的磁共振弥散加权成像(DWI)联合血清C反应蛋白(CRP)对急性缺血性脑梗死时间窗的鉴别价值。方法回顾性分析2021年6月至2023年6月宝鸡市中心医院收治的195例急性缺血性脑梗死患者床资料,其中男111例,女84例,年龄范围57~75岁。按发病至接受磁共振检查前时间分为超急性期组(病程≤6 h)67例、急性期组(病程6~72 h)79例、亚急性期组(≥72~168 h)49例;比较3组患者的DWI检查结果[表观弥散系数(ADC)]及CRP水平,受试者操作特征曲线(ROC)分析DWI联合CRP对急性缺血性脑梗死时间窗的鉴别价值,采用t检验、F检验进行统计分析。结果超急性期组患侧ADC为(0.33±0.08)×10^(-3) mm^(2)/s,低于急性期组的(0.40±0.09)×10^(-3) mm^(2)/s、亚急性期组的(1.56±0.25)×10^(-3) mm^(2)/s,3组比较差异有统计学意义(F=34.455,P<0.05);且超急性期组、急性期组患者患侧ADC值低于健侧,但亚急性期组患者ADC值高于健侧,差异有统计学意义(均P<0.05)。超急性期组CRP为(9.39±3.03)mg/L,高于急性期组(6.01±1.27)mg/L、亚急性期(5.48±1.33)mg/L(q=16.09、712.295,均P<0.05);但急性期组、亚急性期CRP比较差异无统计学意义(q=1.933、P>0.05)。ROC显示ADC鉴别急性缺血性脑梗死超急性期的曲线下面积(AUC)为0.587,灵敏度为100.00%、特异度为38.38%;CRP鉴别急性缺血性脑梗死超急性期的AUC为0.888,灵敏度为73.13%、特异度为96.87%;ADC联合CRP的AUC为0.918,灵敏度、特异度分别为85.07%、86.72%。结论急性缺血性脑梗死患者的ADC与血清CRP水平均可有效鉴别时间窗,ADC鉴别超急性缺血性脑梗死存在高灵敏度优势,CRP则具有高特异度优势,两者联合可进一步优化鉴别效能。

DWI-ASPECTS评分联合血清Hcy、LDL-C、Lp-PLA2对急性脑梗死静脉溶栓患者预后不良的预测价值

目的分析弥散加权成像-阿尔伯塔卒中项目早期计算机断层扫描(DWI-ASPECTS)评分联合血清同型半胱氨酸(Hcy)、低密度脂蛋白胆固醇(LDL-C)、脂蛋白磷脂酶A2(Lp-PLA2)对急性脑梗死(ACI)静脉溶栓患者预后不良的预测价值。方法回顾性分析2021年3月至2023年9月山东大学齐鲁医院德州医院收治的102例ACI患者的临床资料,静脉溶栓3个月后以改良Rankin量表(mRS)评估患者预后,根据mRS评分将患者分为预后良好组(mRS评分≤2分)与预后不良组(mRS评分>2分)。比较两组基线资料及血清Hcy、LDL-C、Lp-PLA2水平及DWI-ASPECTS评分。绘制受试者工作特征(ROC)曲线分析DWI-ASPECTS评分联合血清Hcy、LDL-C、Lp-PLA2对ACI静脉溶栓患者预后不良的预测价值。结果预后不良组有35例患者,预后良好组有67例患者。预后不良组美国国立卫生研究院卒中量表(NIHSS)评分及Hcy、LDL-C、Lp-PLA2水平高于预后良好组,DWI-ASPECTS评分低于预后良好组,差异均有统计学意义(P<0.05)。ROC曲线分析结果显示,DWI-ASPECTS评分联合Hcy、LDL-C、Lp-PLA2评估ACI静脉溶栓患者预后不良的曲线下面积(AUC)大于DWI-ASPECTS评分、Hcy、LDL-C、Lp-PLA2单独预测的AUC(Z=3.548、3.316、3.996、4.009,P<0.05)。结论DWI-ASPECTS评分及血清Hcy、LDL-C、Lp-PLA2均对ACI静脉溶栓患者预后不良具有一定的预测价值,且其联合检测可提高预测价值。

常规MRI、DKI在脑梗死后认知障碍患者中的表现研究

目的分析常规磁共振成像(MRI)、扩散峰度成像(DKI)在脑梗死后认知障碍患者中的表现。方法回顾性分析2020年6月—2023年5月唐山市第三医院收治的98例脑梗死患者的临床资料,治疗出院后随访6个月,统计患者的认知情况,比较认知障碍组和认知正常组的基线资料及常规MRI、DKI参数,分析脑梗死后认知障碍的影响因素及常规MRI、DKI参数对脑梗死后认知障碍的预测效能。结果98例患者中34例出现认知障碍。认知障碍组患者年龄大于认知正常组,脑干梗死占比及额叶FA值低于认知正常组,额叶梗死占比及脑干平均峰度(MK)、脑干平均扩散率(MD)值高于认知正常组(P<0.05),多因素Logistic回归分析结果显示年龄(1.105~1.396)、额叶梗死(1.050~14.406)、脑干MK(1.965~16.819)、脑干MD(10.355~88.636)、额叶部分各向异性(FA)(0.110~0.944)为脑梗死后认知障碍的影响因素(P<0.05)。受试者工作曲线(ROC)结果显示常规MRI、DKI参数联合预测脑梗死后认知障碍的曲线下面积(AUC)值为0.911,明显高于单一参数(P<0.05)。结论额叶梗死、额叶FA值下降、脑干MK及脑干MD值升高的患者更易发生脑梗死后认知障碍,可将常规MRI、DKI参数联合,以预测脑梗死后认知障碍,为脑梗死的诊疗提供参考。

DTI联合DWI对急性脑梗死早期缺血半暗带的定量评估价值

目的分析磁共振弥散张量成像(DTI)联合弥散加权成像(DWI)对急性脑梗死(ACI)早期缺血半暗带(IP)的定量评估价值。方法选取ACI患者80例,均行磁共振DTI和DWI检查,根据患者发病时间将其分为超急性期组(<6h,n=24)、急性期组(6~24h,n=26)和亚急性期组(24~72h,n=30),比较ACI患者梗死中心区、IP区、对侧镜像区的平均扩散系数(DCavg)、表观扩散系数(ADC)、异性指数(FA)值,并比较ACI患者不同发病时期IP区的rDCavg、rADC、rFA值。结果ACI患者不同区域DCavg、ADC、FA值比较:梗死中心区<IP区<对侧镜像区(P<0.05)。ACI患者不同发病时期IP区rDCavg、rADC、rFA值比较:超急性期组>急性期组>亚急性期组(P<0.05)。结论DTI联合DWI检查的相关定量参数对于ACI早期IP具有较高的评估价值,临床可借鉴应用。

磁共振弥散加权成像在急性脑梗死中的诊断价值及磁共振参数分析

目的:探究磁共振弥散加权成像(DWI-MRI)在急性脑梗死中的诊断价值。方法:回顾性分析济南市第三人民医院2023年2月—12月收治的80例疑似急性脑梗死患者的临床资料,所有患者均经头颅磁共振(MRI)、DWI-MRI检查。以临床综合诊断结果为金标准,对比常规MRI及DWI-MRI在急性脑梗死中的诊断效能,并计算与金标准的一致性;对比常规MRI及DWI-MRI对不同时期脑梗死的检出率;对比不同时期脑梗死患者患侧及健侧的表观弥散系数(ADC)值。结果:DWI-MRI技术对急性脑梗死的诊断价值均高于常规MRI检查,差异有统计学意义(P<0.05)。常规MRI检查与金标准的诊断一致性较差(Kappa值=0.232);DWI-MRI检查与金标准的诊断一致性良好(Kappa值=0.857)。不同检查方法的超急性期及急性期脑梗死检出率比较,差异无统计学意义(P>0.05)。超急性期患侧ADC值低于急性期,健侧ADC值高于急性期,差异有统计学意义(P<0.05)。结论:DWI-MRI技术在急性脑梗死诊断中具有较高的临床应用价值,可通过对ADC的分析进一步明确患者病情,为临床诊疗提供有效参考。

功能磁共振成像在评估肾移植术后移植肾功能中的价值

目的:探讨功能磁共振成像(magnetic resonance imaging, MRI)评估肾移植术后移植肾功能的价值。方法:选择2018年1月至2019年12月于南京医科大学第一附属医院接受肾移植手术且移植肾功能稳定的52例患者为研究对象,采用99mTc-DTPA的清除率作为参考肾小球滤过率(reference glomerular filtration rate, rGFR),使用动态增强(dynamic contrast-enhanced, DCE)-MRI估测其移植肾GFR并进行比较。使用偏倚、精度、相关性、一致性和诊断分析,将DCE-MRI估测结果与rGFR进行比较。分别构建4组大鼠模型:同种同体肾移植组(SYN组)、肾脏缺血再灌注组(IRI组)、T细胞介导的排斥反应组(TCMR组)和抗体介导的排斥反应组(ABMR组)。术后7 d行扩散加权成像(diffusion weighted imaging, DWI)序列扫描测量其表观扩散系数(apparent diffusion coefficient, ADC),检查结束后立即处死大鼠,获取移植肾组织行组织学检查。结果:DCE-MRI估测的GFR与rGFR呈显著正相关(r=0.71,P<0.01),一致性分析显示偏倚为-3.544 mL/(min·1.73 m^(2)),精度为15.33 mL/(min·1.73 m^(2)),95%CI为60.07 mL/(min·1.73 m^(2)),DCE-MRI在诊断慢性肾脏病(CKD)3期及以上[GFR<60 mL/(min·1.73 m^(2))]的患者时,曲线下面积为0.91,灵敏度为79.17%,特异度为82.14%。进一步动物实验发现4组间肾脏髓质ADC值均无显著差异,SYN组与IRI组肾脏皮质ADC值无显著差异,TCMR组及ABMR组皮质ADC值较SYN组均显著降低(P<0.05),而TCMR组与ABMR组相比无显著差异。急性排斥组(TCMR组和ABMR组)皮质和髓质ADC值较SYN组、IRI组均显著降低(P均<0.05)。结论:功能MRI可有效且安全地无创评估肾移植术后患者的移植肾功能,具有较高的灵敏度及特异度;动物实验发现功能MRI可用于诊断肾移植术后急性排斥反应。