Impaired cerebrovascular reactivity is associated with recurrent stroke in patients with severe intracranial arterial stenosis: A C02 BOLD fMRI study.

BACKGROUND AND PURPOSE: Severe intracranial atherosclerotic stenosis (SIAS) remains at risk of recurrent ischemic events despite intensive medical management. Exhausted cerebrovascular reserve seems to be associated with higher risk of recurrent stroke. MATERIALS AND METHODS: We used whole brain MRI to estimate basal perfusion using dynamic susceptibility contrast and cerebrovascular reactivity (CVR) to hypercapnic challenge (CO2 inhalation) using BOLD contrast, in 20 patients with symptomatic SIAS (>70%) of the middle cerebral artery (MCA) or the distal internal carotid artery. We studied relationships between individual clinical, biological, radiological baseline characteristics, recurrent ischemic events, basal perfusion parameters (mean transit time, delay, time to peak, cerebral blood flow and volume), and CVR measured in MCA territories (CVRMCA), and reported using laterality indices (LI). RESULTS: Ten patients had an impaired CVR with (|LI| CVRMCA≥0.08). During a mean follow-up of 3.3 years, all recurrent ipsilateral ischemic events occurred within the first year. They were more frequent in impaired CVRMCA group (n=7/10 patients) than in normal CVRMCA group (n=1/10), with different survival curves (log rank, P=0.007). CONCLUSION: Impaired CVR is associated with an increased rate of recurrent stroke in patients with symptomatic SIAS. CVR mapping should be used as a well tolerated method to select higher-risk patients in further therapeutic trials such as endovascular procedures.

What and why: the current situation and future prospects of "ivy sign" in moyamoya disease.

"Ivy sign" is a special imaging manifestation of moyamoya disease (MMD), which shows continuous linear or punctate high intensity along the cortical sulci and subarachnoid space on magnetic resonance images. Ivy sign was reported to reflect the development of compensatory collaterals, and to be closely related to hemodynamic changes and clinical symptoms, and to indicate the postoperative prognosis, in MMD patients. It is a unique and critical marker for MMD. However, due to the lack of consistent criteria, such as definition, grading, and identification standards, ivy sign has not received much attention. We undertook a comprehensive literature search and summarized the current situation regarding ivy sign in MMD in terms of baseline characteristics, detection methods, definition, regional division and distribution patterns, grading criterions, incidence, related factors, the mechanism of ivy sign, and the effects of treatments. We also provided related concerns raised and future prospects relevant to studies about ivy sign in MMD.

Measurement of cerebral vascular reserves with I-123 IMP SPECT without an arterial input function using the microsphere model and radiopharmaceutical dose calibration.

OBJECTIVES: Cerebral vascular reserve (CVR) is an important indicator for the management of and therapy for cerebral arterial occlusive disease (CAOD). Vasodilatory function is measured using the standard IMP-ARG method. The IMP autoradiography (IMP-ARG) method employed here uses a standardized input function, which was derived from 12 patients between 31 and 71 years of age. Because the population of elderly patients continues to increase in Japan, additional therapies are required to assess CVR in elderly patients with chronic cardiopulmonary disease or a history of smoking, in particular. Despite its popularity, alternatives to the IMP-ARG method are necessary. Here, we proposed the microsphere (MS) method without an input function. METHOD: Using this method and the IMP-ARG method, we measured the CVRs of 18 CAOD patients. RESULTS: The CVRs derived with these two methods were significantly and linearly correlated (r = 0.89, p < 0.01). CVRs categorized by severity were also found to correspond between the two methods (κ = 0.87). CONCLUSIONS: Thus, the method proposed here may serve as a supplemental to and be compatible with the IMP-ARG method for the assessment of CVR. Furthermore, the two methods, when used in conjunction, may result in less error than either would alone.

Therapeutic effect of Butylphthalide Injection in elderly patients with acute cerebral infarction and its influence in cerebral hemodynamics and cerebral vascular reserve / 吉林大学学报(医学版)

Objective:To probe the therapeutic effects of Butylphthalide Injection in the elderly patients with acute cerebral infarction (ACI) and its influence in cerebral hemodynamics and cerebral vascular reserve (CVR),and to clarify the pharmacological action mechanism of butylphthalide in treatment of ACI.Methods:A total of 100 cases of elderly patients with ACI were selected as the subjects and divided into observation group and control group according to the serial number on admission.Fifty cases were included in each group.The patients in control group were treated with the conventional treatment, while the patients in observation group were treated with Butylphthalide Injection on the basis of the conventional treatment.The National Institute of Health Stroke Scale (NIHSS) score, the brain hemodynamics indexes of the peak velocity (Vp), the mean velocity (Vm) and the differences of the velocity (DVp, DVm) as well as pulsatility index (PI), CVR of bilateral middle cerebral artery (MCA)of the patients in two groups were observed and compared.The therapeutic effects of the patients in two groups were evaluated and compared.Results:The NIHSS score of the patients in observation group after treatment was significantly lower than that in control group (t=15.420, P<0.05).The therapeutic effects and the clinical efficiency of the patients in observation group were significantly better than those in control group (U=2.225, χ2=5.005, P<0.05).The Vp and Vm of the patients in observation group after treatment were significantly higher than those in control group(t=10.819,t=7.259, P<0.05)and the DVp and DVm were significantly lower than those in control group (t=16.438,t=19.055, P<0.05).The CVR of the patients in observation group after treatment was significantly higher than that in control group(t=6.884, P<0.05)and the PI was significantly lower than that in control group (t=4.979, P<0.05).Conclusion:Butylphthalide Injection can effectively correct the abnormality of brain hemodynamics in the ACI patients, enhance the ability of body in maintaining the stability of cerebral vascular perfusion, improve the neurological symptoms in the patients with ACI, and improve the therapeutic effects.

Cerebrovascular Events During Pregnancy and Puerperium Resulting from Preexisting Moyamoya Disease: Determining the Risk of Ischemic Events Based on Hemodynamic Status Assessment Using Brain Perfusion Single-Photon Emission Computed Tomography.

OBJECTIVE: The purposes of this study were to review the cerebrovascular events (CVE) during pregnancy and puerperium in adults with moyamoya disease (MMD) and to evaluate its risk factors. METHODS: We reviewed electronic medical records on 141 pregnancies in 71 women diagnosed with MMD and this study included only 27 pregnancies (23 patients) diagnosed with MMD before pregnancy. Basal and acetazolamide-stress brain perfusion single-photon emission computed tomography (SPECT) was conducted for 40 hemispheres in 21 pregnancies within 1 year of the gestational period, ranging from 22 months before delivery to 12 months after delivery for evaluation of the hemodynamic status of the patients to devise the MMD treatment strategy. RESULTS: Twelve pregnancies (44.4%) showed CVE during pregnancy or puerperium in the group diagnosed with MMD before pregnancy. All the 12 CVE were ischemic, without any hemorrhagic events. A decreased cerebral vascular reserve capacity (CVRC) on stress SPECT was observed in 25 (62.5%) of the 40 hemispheres, and 18 of these 25 hemispheres showed TIA. In contrast, only 2 of 15 hemispheres which revealed normal CVRC on stress SPECT showed TIA. Overall, a decreased CVRC on stress SPECT imaging was statistically associated with development of CVE (P < 0.001). Furthermore, the clinical type of MMD was also regarded as predictive factor for CVE in this study. Especially, ischemic type MMD revealed a statistical association with the development of CVE (P = 0.014, odds ratio = 16.50). CONCLUSIONS: Assessment of cerebral hemodynamic status with stress SPECT may predict CVE during pregnancy and puerperium.

Effect of Xueshuantong combined with butylphthalide on clinical curative effect, cerebral vascular reserve capacity and serum hs-CRP on acute cerebral infarction / 中国生化药物杂志

Objective To observe the efficacy and effect on cerebral vascular reserve and serum hs-CRP of Xueshuantong combined with butylphthalide in patients with acute cerebral infarction.Methods A total of 140 cases with ACI in Huzhou Central Hospital from August 2015 to July 2016 were divided into the observation group and the control group with 70 cases in each group, according to the order of single and double number.The control group was treated with routine western medicine while giving butylphthalide , and the observation group was given Xueshuantong on the basis of the control group.After two weeks of treatment, the efficacy and CVR, BHI and hs-CRP levels were observed.Results After treatment, the total effective rate of the observation group was 92.86%, and the control group was 81.43%, the difference was statistically significant (χ2 =4.080, P<0.05), there was significant differences of CVR, BHI between two groups (Fgroup =5.534, 4.608, P<0.05), the CVR and BHI increased gradually with time (Ftime =11.325, 9.432, P<0.05), the rised amplitude in observation group was higher than the control group (Finteraction =5.742, 5.016, P<0.05), there were significant differences in the levels of hs-CRP between two groups (Fgroup =7.421, P<0.05), and hs-CRP decreased gradually with time (Ftime =10.185, P<0.05), the decrease of observation group was larger than that of control group(Finteraction =4.824, P<0.05).Conclusion Xueshitong combined with butylphthalide in the treatment of ACI is effective , can better improve cerebral vascular reserve capacity and inhibition of inflammatory response, better than the single use of butylphthalide.

Long term outcome and predictors of ischemic stroke recurrence in adult moyamoya disease.

OBJECTIVE: We sought to identify the clinical outcome and predictors for ischemic stroke recurrence in adults with symptomatic moyamoya disease (MMD). METHODS: We analyzed 104 adult MMD patients with ischemic stroke or TIA registered at our institution. All patients underwent digital subtraction angiography and single photon emission computed tomography to measure disease severity and cerebral vascular reserve (CVR). A Cox regression model was used to identify predictors of recurrent ischemic stroke. RESULTS: Fifty-nine patients were non-surgically treated and 45 patients were surgically treated. In the non-surgical group, the Kaplan-Meier estimate of ischemic stroke recurrence was 1.6% in the first year and 11.8% in the 5th year. Hypertension (hazard ratio [HR]=0.07, 95% confidence interval [CI] 0.01-0.99), diabetes (HR=35.16, 95% CI 2.61-474.16), presence of steno-occlusive lesion in posterior cerebral arteries (HR=17.53, 95% CI 2.02-152.43), and extended or global decreased CVR (HR=13.62, 95% CI 1.55-119.84) were independent predictors of recurrence. In the surgical group, the Kaplan-Meier estimate of ischemic stroke recurrence was 24.4% in the first year and 24.4% in the 5th year. Half of the recurred patients experienced recurrent ischemic strokes postoperatively. Diabetes was the only predictor of recurrent ischemic stroke (HR=6.17, 95% CI 1.31-29.14). CONCLUSIONS: In non-surgically treated MMD, PCA stenosis and CVR were identified as predictors of ischemic stroke recurrence. Diabetes was an independent predictor of recurrent ischemic stroke in both non-surgical and surgically treated MMD groups.

Comparison between Acetazolamide and Dipyridamole Activated SPECT for Cerebral Vascular Reserve Capacity Measurement

Object of this study was to make comparison between acetazolamide and dipyridamole activated SPECT for measurement of cerebral vascular reserve capacity. This study was also carried out to evaluate response in acetazolamide and dipyridamole activated SPECT in relation to clinical parameters, such as Glasgow Coma Scale, Hunt & Hess grade, Fisher grade and Glasgow Outcome Scale. It is concluded from study that. Acetazolamide and dipyridamole activated SPECT study proved to be valuable for cerebral vascular reserve capacity. Dipyridamole activated SPECT study was somewhat equivocal because of systemic vascular dilatation effect, but this problem could be resolved by Gamma Count Ratio. Although there were minimal transient side effect of dipyridamole such as dizziness, no complication.