Steno-occlusive Middle Cerebral Artery Research Articles

Small vessel disease burden and prognosis of recent subcortical ischaemic stroke differ by parent artery atherosclerosis.

Parent artery atherosclerosis is an important aetiology of recent subcortical ischaemic stroke (RSIS). However, comparisons of RSIS with different degrees of parent artery atherosclerosis are lacking. Prospectively collected data from our multicentre cohort (all were tertiary centres) of the Stroke Imaging Package Study between 2015 and 2017 were retrospectively reviewed. The patients with RSIS defined as a single clinically relevant diffusion-weighted imaging positive lesion in the territory of lenticulostriate arteries were categorized into three subgroups: (1) normal middle cerebral artery (MCA) on magnetic resonance angiography and high-resolution magnetic resonance imaging (HR-MRI); (2) low-grade MCA atherosclerosis (normal or <50% stenosis on magnetic resonance angiography and with MCA plaques on HR-MRI); (3) steno-occlusive MCA atherosclerosis (stenosis ≥50% or occlusion). The primary outcome was 90-day functional dependence (modified Rankin Scale score >2). The clinical and imaging findings were compared between subgroups. A total of 239 patients (median age 60.0 [52.0-67.0] years, 72% male) were enrolled, including 140 with normal MCA, 64 with low-grade MCA atherosclerosis and 35 with steno-occlusive MCA atherosclerosis. Patients with steno-occlusive MCA atherosclerosis had the largest infarct volume. Low-grade MCA atherosclerosis was independently associated with cerebral microbleeding, more severe perivascular spaces in basal ganglia and higher total cerebral small vessel disease burden. Low-grade MCA atherosclerosis was an independent determinant of 90-day functional dependence (odds ratio 3.897; 95% confidence interval 1.309-11.604). Our study suggested RSIS with varying severity of parent artery atherosclerosis exhibits distinctive clinical and neuroimaging characteristics, with low-grade MCA atherosclerosis associating with higher cerebral small vessel disease burden and worse prognosis.

Multi-assessment of critical steno-occlusive middle cerebral arteries: transcranial Doppler combined with magnetic resonance angiography

BackgroundAccurate assessment of a stenotic or occluded middle cerebral artery (MCA) is essential before making optimal therapeutic decisions. However, complete occlusion is not always easy to determine for both magnetic resonance angiography (MRA) and neurologists. We aimed to study noninvasive technology using transcranial Doppler (TCD) combined with MRA to assess severe stenosis and occlusion of the MCA. MethodsWe studied consecutive patients with severe steno-occlusive MCA by digital subtraction angiography from Oct. 2011 to Mar. 2020 in our stroke center. Hemodynamic measurements of TCD, including peak velocity (PSV), mean flow velocity (MFV) and pulse index (PI), were recorded specifically at the steno-occlusive site by MRA. ResultsA total of 152 MCAs of 148 patients were enrolled (60.0 ± 11.5 y, 107 male), including 82 severe stenotic MCAs and 70 occluded MCAs (Group S & Group O) by DSA. There were 86/152 (57%) MCAs showing discontinuity in MRA, which was significantly distributed more in Group O than in Group S (84% vs. 33%, P < 0.001). The PSV and MFV in Group S were greater (264 ± 78 cm/s vs. 33 ± 34 cm/s and 182 ± 61 cm/s vs. 21 ± 23 cm/s, respectively, P < 0.001), while the PI in Group O was greater (0.98 ± 0.49 vs. 0.72 ± 0.17, P < 0.001). PSV was positively correlated with severe MCA stenosis (β = 0.036, P < 0.001, OR = 0.965, 95% confidence interval (CI): 0.952–0.978). In severe steno-occlusive MCA, using PSV and MFV to detect MCA severe stenosis yielded areas under the curve of 0.983 (CI: 0.964–1.0) and 0.982 (CI: 0.962–1.0), respectively. The cutoff points of PSV ≥ 77 cm/s and MFV ≥ 51 cm/s both yielded an optimized sensitivity of 96.3% and specificity of 98.6%. ConclusionThe critical velocity at the steno-occlusive site is reliable for distinguishing between severe MCA stenosis and occlusion.

Association Between Steno-Occlusive Middle Cerebral Artery and Basal Ganglia Perivascular Spaces.

Objectives: Enlarged perivascular spaces in the basal ganglia (BG-EPVS) share common vascular risk factors with atherosclerosis. However, little is known about the relationship between steno-occlusive middle cerebral artery (MCA) and BG-EPVS. In this cross-sectional study, we aimed to test the hypothesis that severe MCA stenosis or occlusion is associated with increased MRI-visible BG-EPVS.Methods: We retrospectively reviewed 112 patients with a steno-occlusive MCA from Fujian Medical University Union Hospital between January 2014 and December 2018. We rated BG-EPVS, white matter hyperintensities (WMH), and lacunes as markers of cerebral small vessel disease (CSVD) on magnetic resonance image (MRI). The severity of steno-occlusive MCA was assessed by computed tomography angiography (CTA) and was classified into moderate (50–69%), severe (70–99%), and occlusion (100%). We evaluated the association of steno-occlusive MCA for >10 BG-EPVS using logistic regression model adjusted for age, gender, hypertension, MR-visible WMH, and lacunes. We also compared the number of BG-EPVS between the affected side and unaffected side in patients with only unilateral steno-occlusive MCA.Results: In multivariable logistic regression analysis, age (OR = 1.07, 95%CI: 1.03–1.13, p = 0.003), hypertension (OR = 2.77, 95%CI: 1.02–7.51, p = 0.046), severe MCA stenosis (OR = 3.65, 95%CI: 1.12–11.87, p = 0.032), or occlusion (OR = 3.67, 95%CI: 1.20–11.27, p = 0.023) were significantly associated with >10 BG-EPVS. The number of BG-EPVS in the affected side was higher than the unaffected side in patients with severe MCA stenosis (12 [9−14] vs. 8 [6−11], p = 0.001) or occlusion (11 [7−14] vs. 8 [5−11], p = 0.028).Conclusions: BG-EPVS were more prevalent in patients with severe MCA atherosclerosis. Our findings suggest a biological link between severe steno-occlusive MCA and increased BG-EPVS. These results need confirmation in prospective studies.

Mismatch of cognition and neural networks in asymptomatic middle cerebral artery steno-occlusive disease.

The role of intracranial steno-occlusive disease in cognitive impairment and dementia is unclear and has not been well studied. A total of 32 consecutive patients (13 males, aged 54±12years) with asymptomatic steno-occlusive middle cerebral artery (MCA) disease, defined as >70% stenosis on maximum intensity projection images or a complete signal loss of MCA trunk on magnetic resonance angiography, and 20 age- and education-matched normal controls (12 males, 60±8years old) were compared for neuropsychological performance, gray matter volume and neural network analysis. The patient group did not show a significant decrease in gray matter volume or cognitive tests except for their performance on the grooved pegboard test. However, graph analysis of resting-state functional magnetic resonance imaging showed significant decreases in network strength, global efficiency and the clustering coefficient, as well as a longer characteristic path length (P<0.05). The diffusive decrease pattern was particularly located in interhemispheric connectivity and there was no compensatory hyperconnectivity in any brain regions. In asymptomatic steno-occlusive MCA disease, cognition and neural network changes are mismatched and have underlying pathophysiological mechanisms that are different from those of neurodegenerative disease.

Ultra-low-dose multiphase CT angiography derived from CT perfusion data in patients with middle cerebral artery stenosis.

Computed tomography (CT) perfusion (CTP) source images contain both brain perfusion and cerebrovascular information, and may allow a dynamic assessment of collaterals. The purpose of the study was to compare the image quality and the collaterals identified on multiphase CT angiography (CTA) derived from CTP datasets (hereafter called CTPA) reconstructed with iterative model reconstruction (IMR) algorithm in patients with middle cerebral artery (MCA) steno-occlusion with those of routine CTA. Consecutive patients with a unilateral MCA steno-occlusion underwent non-contrast CT (NCCT), CTP, and CTA. CTPA images were reconstructed from CTP datasets. The vascular attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of routine CTA and CTPA were measured and analyzed by Student's t test. Subjective image quality and collaterals were scored and compared using the Wilcoxon signed-rank test. Fifty-eight patients (mean age 61.7 years, 78% males, median National Institutes of Health Stroke Scale score = 12) were included. The effective radiation dose of CTP was 1.28 mSv. The vascular attenuation, SNR, CNR, and the image quality of CTPA were considerably higher than that of CTA (all, p < 0.001). Collaterals were rated higher on CTPA compared with CTA (1.79 ± 0.64 vs. 1.22 ± 0.84, p < 0.001). Fifty-three percent of patients with poor collaterals assessed on single-phase CTA had good collaterals on CTPA. CTPA derived from CTP datasets reconstructed with IMR algorithm offers image quality comparable to routine CTA and provides time-resolved evaluation of collaterals in patients with MCA ischemic disease.

Related Factors of Asymmetrical Vein Sign in Acute Middle Cerebral Artery Stroke and Correlation with Clinical Outcome

The aim of our study was to analyze the related factors of asymmetrical cortical vein sign (ACVS) and asymmetrical medullary vein sign (AMVS) on susceptibility-weighted imaging (SWI) in patients with acute middle cerebral artery (MCA) stroke and whether their presence can be used as an independent predictor for clinical outcome. According to the presence of ACVS and AMVS on SWI, 124 patients with acute MCA stroke within 3 days were divided into several different groups. In addition, those patients were also divided into good and poor outcome group by using the modified Rankin Scale at 3 months after stroke. We investigated respectively the differences in magnetic resonance imaging findings and the clinical data among those different groups. The ACVS was demonstrated in 90 of 124 patients. Of the 90 patients, 47 were accompanied with the AMVS. The rest of 34 patients showed no ACVS and AMVS. The infarct size and MCA status showed significant differences among the ACVS+, AMVS+ group; ACVS+, AMVS- group; and ACVS-, AMVS- group (all P < .001). Moreover, the ACVS, AMVS, and MCA occlusion were more common in the poor outcome group (all P< .001). In the multivariate logistic regression, AMVS (P = .027; odds ratio, 2.37; 95% confidence interval, 1.23-8.73) was associated with poor outcome. The ACVS and AMVS were correlated to the status of MCA steno-occlusion and infarct size, whereas the AMVS was proved to be independently related to the stroke severity and poor outcome rather than the ACVS.

Non-moyamoya vessel network formation along steno-occlusive middle cerebral artery.

In this study, we sought to examine the prevalence and clinical relevance of deep tiny flow voids (DTFV) in patients with steno-occlusive middle cerebral artery (MCA) disease on high-resolution MRI (HRMRI). We retrospectively reviewed the HRMRI and clinical data of 477 patients with MCA steno-occlusive disease. The presence and distribution of DTFV, defined as 3 or more flow voids along the affected MCA on at least 2 consecutive T2-weighted image slices on HRMRI, were observed. The relationships among DTFV, the degree of stenosis (mild <50%, moderate 50%-70%, severe 70%-99%, and occlusion), and infarctions were analyzed. To clarify the difference between DTFV and moyamoya collaterals, we compared the HRMRI findings of the patients with DTFV and 102 patients with moyamoya disease. The prevalence of DTFV was 1.4% in mild stenosis, 12.8% in moderate stenosis, 40.6% in severe stenosis, and 50.7% in MCA occlusions. Of the 112 patients with DTFV, 57 (50.9%) had all 4 quadrants (superior, inferior, dorsal, and ventral sides) of the MCA involved. DTFV were more common in asymptomatic patients than in symptomatic patients with severe stenosis (49.3% vs 30.9%, p = 0.025) and occlusions (68.0% vs 41.7%, p = 0.033). Obvious flow voids in the basal ganglia region were observed in 58 patients (56.9%) with moyamoya disease but in none of the patients with DTFV (p < 0.001). DTFV are common in patients with severe steno-occlusive MCA disease, especially in asymptomatic patients. We hypothesize that DTFV originate from new vessel network formation in response to chronic cerebral ischemia.

Abstract WP130: Non-moyamoya Vessel Network Formation Along Steno-occlusive Middle Cerebral Artery

Introduction: “Deep tiny flow voids” (DTFV), defined as three or more flow voids along occlusive middle cerebral artery(MCA) on at least two consecutive T2-weigthed image slices of high-resolution magnetic resonance imaging(HR-MRI), were recently proposed as a sign of pathological collaterals formation. Objective: In this study, we sought to examine the prevalence and clinical relevance of DTFV in patients with steno-occlusive MCA disease. Methods: We retrospectively reviewed the HR-MRI and clinical data of 477 patients with MCA steno-occlusive disease. The presence and distribution of DTFV were observed. The relationships among DTFV, the degree of stenosis, and infarctions were analyzed. To clarify the difference between DTFV and moyamoya collaterals, we also compared the HR-MRI findings of 102 patients with moyamoya disease and the patients with DTFV. Results: DTFV were revealed in 112 (23.5%) patients. The prevalence of DTFV was 1.4% in mild stenosis (&lt;50%),12.8% in moderate stenosis (50-70%), 40.6% in severe stenosis (70-99%) and 50.7% in occlusions of MCA. DTFV were more common in asymptomatic than in symptomatic patients with severe stenosis (49.3% vs 30.9%, p=0.025) and occlusions (68.0% vs 41.7%, p=0.033). As high as 71.4% DTFV distributed in more than 3 of 4 quadrants around MCA stem. Obvious flow voids in basal ganglia region were observed in 58 (56.9%) patients with Moyamoya disease, but in none of patients with DTFV (p&lt;0.001). Conclusions: DTFV are common in patients with severe steno-occlusive MCA, especially in asymptomatic patients. We hypothesize DTFV are suggestive of non-Moyamoya vessel network formation due to chronic hypoxia and ischemia.

High-resolution magnetic resonance wall imaging findings of Moyamoya disease.

Diagnosis of Moyamoya disease (MMD) is based on the characteristic angiographic findings. However, differentiating MMD from intracranial atherosclerotic disease (ICAD) is difficult. We compared vessel wall imaging findings on high-resolution magnetic resonance imaging between MMD and ICAD. High-resolution magnetic resonance imaging was performed on 32 patients with angiographically proven MMD and 16 patients with acute infarcts because of ICAD. Bilateral internal carotid arteries and steno-occlusive middle cerebral artery were analyzed for wall enhancement and remodeling. Enhancement patterns and distribution were different. Most patients with MMD (90.6%) showed concentric enhancement on distal internal carotid arteries and middle cerebral arteries, whereas focal eccentric enhancement was observed on the symptomatic segment in ICAD. MMD was characterized by middle cerebral artery shrinkage; the remodeling index and wall area were lower in MMD than in ICAD (remodeling index, 0.19±0.11 versus 1.00±0.43; wall area, 0.32±0.22 versus 6.00±2.72; P<0.001). MMD was characterized by concentric enhancement on bilateral distal internal carotid arteries and shrinkage of middle cerebral artery, regardless of symptoms.

A non-invasive technique for visualization of microvessels in asymptomatic patients with middle cerebral artery steno-occlusion

We determined whether 7T magnetic resonance angiography (MRA) could be used for clearly observing microvessels in a clinically asymptomatic patient with steno-occlusion of the middle cerebral artery (MCA). We utilized 3T magnetic resonance imaging to obtain the brain images of a clinically asymptomatic patient and noted MCA steno-occlusion. In comparison with 3T MRA, 7T MRA could clearly delineate the microvessels, including lenticulostriate arteries and presumed collaterals, and our observation was comparable to that with conventional digital subtraction angiography. We report an interesting case of a clinically asymptomatic patient with MCA steno-occlusion.

Microvascular imaging of asymptomatic MCA steno-occlusive patients using ultra-high-field 7T MRI

It is common that physicians are faced with patients who have severe steno-occlusion of intracranial arteries in the absence of clinical symptoms. This study is to determine whether a 7T magnetic resonance angiogram (MRA) could provide the improved depiction of microvessels of asymptomatic patients with steno-occlusive middle cerebral artery (MCA) and possible clues for diagnosis of their clinical symptoms. All the patients who were identified as severe MCA steno-occlusions underwent a 7T MRA study. Three of these also underwent conventional angiography (TFCA). The vascular densities around the steno-occlusive MCA and posterior cerebral artery (PCA) branches as control vessels were measured and the difference between the median values of 7T and 3T MRA data was also analyzed. The results of 7T MRA revealed numerous microvessels not visible by conventional MRA. These 7T MRA images were also comparable to those obtained by an invasive conventional angiography (TFCA). The median values of vascular densities observed by 7T MRA were significantly higher than those by 3T MRA (5.28 at 7T vs. 1.45 at 3T for steno-occlusive MCA, p = 0.012, while 3.39 at 7T vs. 3.32 at 3T for normal PCA, p = 0.093). Ultra-high-field 7T MRA is a totally noninvasive angiographic technique that is capable of visualizing microvascular circulation that is usually difficult with conventional MRA. This visualization technique, therefore, could provide an important avenue on the diagnosis of steno-occlusion as well as the search of the roles of the microvessel, especially collaterals, in the preservation of normal blood circulation in patients with asymptomatic MCA steno-occlusion.

Spotlight on the May 24 Issue

#### Notable in Neurology This issue features an article examining the prevalence and clinical relevance of deep tiny flow voids in patients with steno-occlusive middle cerebral artery disease and another analyzing the molecular mechanism of mutant HTRA1-dependent cerebral small vessel disease in heterozygous individuals. A featured article focuses on the influence of preexisting disabilities, age and stroke service level on standardized IV thrombolysis rates in acute ischemic stroke. ### A reappraisal of mortality after epilepsy surgery This study demonstrates that epilepsy surgery reduces mortality when patients become seizure-free or when seizure severity is ameliorated. Long-term mortality was assessed in …

Leptomeningeal collateral and cerebral hemodynamics in patients with ICA and MCA steno-occlusion

<title/>Objectives: The purpose of our study was to evaluate the correlation between fluid-attenuated inversion recovery (FLAIR) images of hyperintense vessel (HV), a representative of leptomeningeal vessels (LMVs), and cerebral vascular hemodynamic status in patients with steno-occlusive disease of the internal carotid artery (ICA) and middle cerebral artery (MCA).Methods: Sixty-eight patients with unilateral ICA or MCA stenosis or occlusion were enrolled. Correlations between hyperintense vessel (HV) on FLAIR images and hemodynamic status measured by quantitative single-photon emission computed tomography data were evaluated in four groups: affected (A) and non-affected (B) hemispheres in HV-positive patients, and affected (C) and non-affected (D) hemispheres in HV-negative patients.Results: The presence of HV was most frequently seen on affected hemispheres in patients with MCA and ICA occlusions. HV was significantly higher in the anterior communicating artery (AcomA) (−), posterior communicating artery (PcomA) (−) group than in other groups, which included either or both AcomA and PcomA (P = 0·008). The presence of HV had a significant correlation with transdural anastomosis (P = 0·046) and LMV (P = 1·64×10−9). No significant difference was observed in resting regional cerebral blood flow among the four groups. Vascular reserve in group A was significantly less compared to other groups (P = 0·021).Conclusions: HV is related to the hemisphere with severe ICA and MCA steno-occlusion when the circle of Willis is insufficient. The HV-positive hemisphere on the steno-occlusive side shows a lower vascular reserve than that in the contralateral hemisphere or HV-negative hemispheres.

Association of Internal Border Zone Infarction with Middle Cerebral Artery Steno-Occlusion

Background: Demonstrating the precise anatomical area of the internal border zone (IB) by brain imaging has been unclear, and it is not well known which relevant arteries are associated with IB infarction. Methods: Patients with IB infarctions were selected from 748 consecutive patients with acute ischemic stroke. The IB infarctions were identified by coronal diffusion-weighted imaging, excluding lesions over the upper pole of the lateral ventricle. The angiographic findings of the internal carotid artery (ICA) and middle cerebral artery (MCA), on contrast-enhanced MRA, were evaluated in the patients with and without IB infarction. Results: Thirty patients met the criteria for an IB infarction: 7 had MCA steno-occlusion without ICA disease, and 23 had ICA steno-occlusion. Sixty-one patients had ICA steno-occlusion without IB infarction. The multiple logistic regression analysis showed that a more than moderate degree of steno-occlusion of the MCA was a significant factor (OR, 11.32; p = 0.006) associated with IB infarction; whereas that of the ICA was not significant (OR, 2.19; p = 0.298). Conclusion: The results of this study suggest that IB infarctions were associated with MCA steno-occlusion. ICA disease resulting in IB infarctions would be expected to have significant MCA steno-occlusion causing hemodynamic compromise.