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Enlarged perivascular spaces (EPVS) are common in cerebral small vessel disease (CSVD) and have been identified as a marker of dysfunctional brain clearance. However, it remains unknown if the enlargement occurs predominantly around arteries or veins. We combined in vivo ultra-high-resolution MRI and histopathology to investigate the spatial relationship of veins and arteries with EPVS within the basal ganglia (BG). Furthermore, we assessed the relationship between the EPVS and measures of blood-flow (blood-flow velocity, pulsatility index) in the small arteries of the BG. Twenty-four healthy controls, twelve non-CAA CSVD patients, and five probable CAA patients underwent a 3 tesla [T] and 7T MRI-scan, and EPVS, arteries, and veins within the BG were manually segmented. Furthermore, the scans were co-registered. Six autopsy-cases were also assessed. In the BG, EPVS were significantly closer to and overlapped more frequently with arteries than with veins. Histological analysis showed a higher proportion of BG EPVS surrounding arteries than veins. Finally, the pulsatility index of BG arteries correlated with EPVS volume. Our results are in line with previous works and establish a pathophysiological relationship between arteries and EPVS, contributing to elucidating perivascular clearance routes in the human brain., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

To retrospectively explore the role of magnetic resonance imaging (MRI) diffusion tensor imaging (DTI) in analyzing the corticospinal tract injury in acute cerebral anterior circulation infarction in the basal ganglia region and the correlation between DTI parameters and neurological function scores, patients with acute cerebral infarction and stroke had undergone plain MRI and DTI sequence scanning were enrolled. Diffusion tensor tractography was used to perform 3-dimensional reconstruction of bilateral corticospinal tracts (CST). The image data were processed to obtain fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values, and the correlation between the DTI parameters and neurological function scores of National Institutes of Health Stroke Scale (NIHSS) was evaluated. A total of thirty-two patients with acute ischemic cerebral infarction were retrospectively enrolled, including 19 males and 13 females with a mean age 63.22 ± 7.78 years. The CST score was 0 in 2 (6.25%) patients, 1 in 9 (28.13%), 2 in 9 (28.13%), 3 in 7 (21.88%), and 4 in 5 (15.63%). The FA value significantly (P = .01) decreased (0.52 ± 0.03 vs 0.62 ± 0.04) on the ischemic side compared with that on the normal side. A significant (P < .05) difference was detected in the number of nerve fibers (223.3 ± 110.0 vs 246.7 ± 104.4) rather than in the ADC values (0.86 ± 0.06 vs 0.84 ± 0.06) between the ischemic and healthy sides. The FA and ADC values were not significantly (P > .05) different according to the CST scores 0, 1, 2, 3, or 4 between the ischemic and healthy sides. There was a significant (P < .05) negative correlation between the FA value on the infarcted side and the NIHSS score. In conclusion, with the DTI technology, varying degrees of damage to the corticospinal tract at the infarcted side can be detected and important clinical information can be provided for the diagnosis and prognosis of acute cerebral infarction by evaluating the degree of corticospinal tract injury., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background and Purpose: Post-stroke movement disorders (PMDs) following ischemic lesions of the basal ganglia (BG) are a known entity, but data regarding their incidence are lacking. Ischemic strokes secondary to proximal middle cerebral artery (MCA) occlusion treated with thrombectomy represent a model of selective damage to the BG. The aim of this study was to assess the prevalence and features of movement disorders after selective BG ischemia in patients with successfully reperfused acute ischemic stroke (AIS)., Methods: We enrolled 64 consecutive subjects with AIS due to proximal MCA occlusion treated with thrombectomy. Patients were clinically evaluated by a movement disorders specialist for PMDs onset at baseline, and after 6 and 12 months., Results: None of the patients showed an identifiable movement disorder in the subacute phase of the stroke. At 6 and 12 months, respectively, 7/25 (28%) and 7/13 (53.8%) evaluated patients developed PMDs. The clinical spectrum of PMDs encompassed parkinsonism, dystonia and chorea, either isolated or combined. In most patients, symptoms were contralateral to the lesion, although a subset of patients presented with bilateral involvement and prominent axial signs., Conclusion: Post-stroke movement disorders are not uncommon in long-term follow-up of successfully reperfused AIS. Follow-up conducted by a multidisciplinary team is strongly advisable in patients with selective lesions of the BG after AIS, even if asymptomatic at discharge., (© 2024 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)

Background: The basal ganglia, a group of subcortical nuclei located deep in the insular cortex, are responsible for many functions such as motor learning, emotion, and behavior control. Nowadays, because it has been shown that deep brain stimulation and insular tumor surgery can be performed by endovascular treatment, the importance of the vascular anatomy of the basal ganglia is being increasingly recognized., Objective: To explain the arterial blood supply of the basal ganglia using white matter dissection., Methods: The Klingler protocol was used to prepare 12 silicone-injected human hemispheres. The dissections were performed from lateral to medial with the fiber dissection technique to preserve arteries., Results: The globus pallidus blood supply came from the medial lenticulostriate, lateral lenticulostriate, and anterior choroidal arteries; the substantia nigra and subthalamic nucleus were supplied by the branches of posterior cerebral artery; the putamen was supplied by the lateral and medial lenticulostriate arteries; and the caudate nucleus was supplied by the lateral lenticulostriate and medial lenticulostriate arteries and the recurrent artery of Heubner., Conclusion: Knowledge of the detailed anatomy of the basal ganglia and its vascular supply is essential for avoiding postoperative ischemic complications in surgeries related to the insula. In addition, knowledge of this anatomy and vascular relationship opens the doors to endovascular deep brain stimulation treatment. This study provides a 3-dimensional understanding of the blood supply to the basal ganglia by examining it using the fiber dissection technique. Further studies could use advanced imaging modalities to explore the vascular relationships with critical structures in the brain., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background and Purpose: Haemodynamics around the middle cerebral artery (MCA) and lenticulostriate arteries is believed to play important roles in the vascular rupture and local haemodynamics is subject to vascular geometry. Nonetheless, the relationship between the geometric features of MCA and spontaneous basal ganglia intracerebral haemorrhage (ICH) has not been investigated. To examine the relationship between the MCA geometric features and spontaneous basal ganglia ICH., Methods: This study was of retrospective and observational nature. The study recruited 158 consecutive hospitalised patients with consecutive CT-confirmed unilateral spontaneous basal ganglia ICH. Clinical data were extracted from electronic medical records, and imaging data were evaluated by two trained radiologists. The MCA-related geometric features were examined and their relationship with spontaneous basal ganglia ICH was analysed. Haemodynamic analyses under different MCA structural features were conducted., Results: Compared with the contralateral MCA, the ipsilateral MCA had greater M1 diameter ratio (proximal/distal) and a smaller M1/M2 angle and MCA bifurcation angle (p＜0.01). Imaging study showed differences in the MCA shape in both sides on coronal plane (p＜0.05). These MCA features were significantly correlated with the spontaneous ICH in basal ganglia. The greater M1 diameter ratio (proximal/distal), the inferior-oriented M1, the smaller M1/M2 angle and the superior-oriented M1 conditions increased the pressure, from high to low. The greater M1 diameter ratio (proximal/distal) and the inferior-oriented M1 increased the shear stress at the distal end of M1 segment., Conclusions: The geometric features of MCA were significantly related to the spontaneous ICH in basal ganglia. The risk of haemorrhage, from high to low, included the greater M1 diameter ratio (proximal/distal), the inferior-oriented M1 (distal end), the smaller M1/M2 angle and the superior-oriented M1. Mechanistically, these vascular structural features contribute to increased vascular wall pressure and shear stress, which eventually lead to haemorrhage., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Mineralizing angiopathy is a unique, age-specific stroke syndrome characterized by basal ganglia infarction and lenticulostriate calcification after minor head injury in early childhood. There is limited understanding of the pathophysiology, course, and clinical outcome of this syndrome. We describe the clinical and radiographical phenotype of a single-center, consecutively enrolled cohort of children with mineralizing angiopathy from January 2002 to January 2020 and provide a comparative analysis to previously published literature. Fourteen children were identified. Previously unreported findings include: stroke onset in eight children older than 18 months; presence of basal ganglia hemorrhage in four; multifocal basal ganglia infarcts in three; presence of additional non-basal ganglia calcifications in three; and presence of thrombophilia in one. Seven children had moderate-to-severe neurological deficits. There was no symptomatic stroke recurrence (mean follow-up 3y 7mo, SD 1y 7mo). Our expanded phenotype highlights distinct characteristics of mineralizing angiopathy in children and has the potential to inform future research. What this paper adds Children with mineralizing angiopathy are often misdiagnosed as having a limb fracture despite normal x-rays. A magnetic resonance imaging-only approach may miss this entity. Non-contrast computed tomography, in addition to MRI is recommended to identify calcifications in idiopathic arterial ischemic stroke. Most children have moderate-to-severe neurological sequela., (© 2021 Mac Keith Press.)

Enlarged perivascular spaces (EPVS) are widely considered as a feature of cerebral small vessel diseases (SVD), but its underlying pathology is still under active investigation. The aim of this study was to explore the association between hemoglobin level and the severity of EPVS. Consecutive patients with acute ischemic stroke who underwent baseline MRI scan and hemoglobin testing were evaluated. EPVS in basal ganglia (BG) and central semiovale (CS) were rated with a validated 4-point semiquantitative scale (0 = none; 1 = 1-10; 2 = 11-20; 3 = 21-40; and 4 ≥ 40). Bivariate logistic regression models were used to identify the associations of hemoglobin with predefined high-degree (score > 1) CS-EPVS and BG-EPVS. Multinomial logistic regression models were used to analyze the associations between hemoglobin and CS-/BG-EPVS predominance patterns. A total of 401 patients were included in the final analysis, 94 patients (23.4%) had a high degree of CS-EPVS and 45 patients (11.2%) had a high degree of BG-EPVS. Compared with tertile 1 of hemoglobin, tertile 3 of hemoglobin was independently associated with high degree of CS-EPVS after adjusting for other features of SVD (odds ratio [OR] 2.399, 95% confidence interval [CI] 1.315-4.379, P = 0.004) and potential confounding factors (OR 2.611, 95% CI 1.346-5.066, P = 0.005). In multinomial logistic regression models, compared with tertile 1 of hemoglobin, tertile 2 (OR 2.463, 95% CI 1.195-5.075, P = 0.015) and tertile 3 (OR 2.625, 95% CI 1.102-6.251, P = 0.029) of hemoglobin were associated with higher odds of BG-EPVS = CS-EPVS pattern, and tertile 3 of hemoglobin (OR 2.576, 95% CI 1.004-6.608, P = 0.049) was associated with higher odds of BG-EPVS < CS-EPVS pattern. Elevated hemoglobin level was independently associated with high degree of CS-EPVS and higher odds of CS-EPVS predominance pattern, but not with BG-EPVS, which support that the topography of EPVS is characteristic. However, the pathogenesis linking hemoglobin and CS-EPVS is unclear and still needs further investigation.

The purpose of this study was to assess whole brain and regional patterns of cerebrovascular reactivity (CVR) abnormalities in HIV-infected women using quantitative whole brain arterial spin labeling (ASL). We hypothesized that HIV-infected women would demonstrate decreased regional brain CVR despite viral suppression. This cross-sectional study recruited subjects from the Bay Area Women's Interagency Health Study (WIHS)-a cohort study designed to investigate the progression of HIV disease in women. In addition to conventional noncontrast cerebral MRI sequences, perfusion imaging was performed before and after the administration of intravenous acetazolamide. CVR was measured by comparing quantitative ASL brain perfusion before and after administration of intravenous acetazolamide. In order to validate and corroborate ASL-based whole brain and regional perfusion, phase-contrast (PC) imaging was also performed through the major neck vessels. FLAIR and susceptibility weighted sequences were performed to assess for white matter injury and microbleeds, respectively. Ten HIV-infected women and seven uninfected, age-matched controls were evaluated. Significant group differences were present in whole brain and regional CVR between HIV-infected and uninfected women. These regional differences were significant in the frontal lobe and basal ganglia. CVR measurements were not significantly impacted by the degree of white matter signal abnormality or presence of microbleeds. Despite complete viral suppression, dysfunction of the neurovascular unit persists in the HIV population. Given the lack of association between CVR and traditional imaging markers of small vessel disease, CVR quantification may provide an early biomarker of pre-morbid vascular disease.

Cerebral small vessel disease (SVD) contributes to 25% of ischemic strokes and 45% of dementias. We aimed to investigate the role of cerebral blood flow (CBF) and intracranial pulsatility in SVD. We scanned 60 patients with minor ischemic stroke, representing a range of white matter hyperintensities (WMH). We rated WMH and perivascular spaces (PVS) using semi-quantitative scales and measured WMH volume. We measured flow and pulsatility in the main cerebral vessels and cerebrospinal fluid (CSF) using phase-contrast MRI. We investigated the association between flow, pulsatility and SVD features. In 56/60 patients (40 male, 67.8±8.3 years) with complete data, median WMH volume was 10.7 mL (range 1.4-75.0 mL), representing median 0.77% (0.11-5.17%) of intracranial volume. Greater pulsatility index (PI) in venous sinuses was associated with larger WMH volume (e.g. superior sagittal sinus, β = 1.29, P  < 0.01) and more basal ganglia PVS (e.g. odds ratio = 1.38, 95% confidence interval 1.06, 1.79, per 0.1 increase in superior sagittal sinus PI) independently of age, sex and blood pressure. CSF pulsatility and CBF were not associated with SVD features. Our results support a close association of SVD features with increased intracranial pulsatility rather than with low global CBF, and provide potential targets for mechanistic research, treatment and prevention of SVD.

Objective: Arteriovenous malformations (AVMs) of the basal ganglia (BG) and thalamus are associated with elevated risks of both hemorrhage if left untreated and neurological morbidity after resection. Therefore, stereotactic radiosurgery (SRS) has become a mainstay in the management of these lesions, although its safety and efficacy remain incompletely understood. The aim of this retrospective multicenter cohort study was to evaluate the outcomes of SRS for BG and thalamic AVMs and determine predictors of successful endpoints and adverse radiation effects., Methods: The authors retrospectively reviewed data on patients with BG or thalamic AVMs who had undergone SRS at eight institutions participating in the International Gamma Knife Research Foundation (IGKRF) from 1987 to 2014. Favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RICs). Multivariable models were developed to identify independent predictors of outcome., Results: The study cohort comprised 363 patients with BG or thalamic AVMs. The mean AVM volume and SRS margin dose were 3.8 cm3 and 20.7 Gy, respectively. The mean follow-up duration was 86.5 months. Favorable outcome was achieved in 58.5% of patients, including obliteration in 64.8%, with rates of post-SRS hemorrhage and permanent RIC in 11.3% and 5.6% of patients, respectively. Independent predictors of favorable outcome were no prior AVM embolization (p = 0.011), a higher margin dose (p = 0.008), and fewer isocenters (p = 0.044)., Conclusions: SRS is the preferred intervention for the majority of BG and thalamic AVMs. Patients with morphologically compact AVMs that have not been previously embolized are more likely to have a favorable outcome, which may be related to the use of a higher margin dose.

Background: A common-stem origin of lenticulostriate arteries (CS-LSAs) is an anatomical variation that supplies a moderate to large section of the basal ganglia. We hypothesized that CS-LSAs with a patent orifice are located at distal positions of the acute-occluded middle cerebral artery (MCA) and that the blood flow of CS-LSAs is supplied by pail arterial anastomoses and results in hypoperfusion of CS-LSAs, similar to a deep watershed (DWS) infarction., Objective: Our study evaluated the possibility of CS-LSAs in patients with DWS infarction and MCA occlusion and also assessed the safety of endovascular therapy (ET) in these patients., Methods: A cohort of consecutive patients with DWS infarction and MCA occlusion and in whom full recanalization via ET was achieved were identified. Patients were divided into two groups based on the presence of CS-LSAs observed during ET. In addition, radiological and clinical data were retrospectively analyzed., Results: Thirty-three patients were included, and CS-LSAs were observed in 48.5% (16/33) of patients. The possibility (72.2%, 13/18) of CS-LSAs was high in patients with DWS infarction companied with basal ganglia infarction. A good clinical outcome was similar in patients with CS-LSAs and basal ganglia infarction and in patients without CS-LSAs and basal ganglia infarction (69.2% vs. 81.8%, P = 0.649)., Conclusions: The possibility of CS-LSAs was 48.5% in patients with DWS infarction and MCA occlusion, and the revascularization procedure was safe and feasible in these patients despite the moderate-to-large basal ganglia infarction.

Background/purpose: In acute proximal middle cerebral artery (MCA) occlusion covering the lenticulostriate arteries (LSA), ischemic tolerance of basal ganglia is limited due to supposed lack of collateral supply. However, in several patients, basal ganglia (BG) infarction was absent after successful mechanical thrombectomy (MTE). Purpose of our study was to evaluate predictors for BG viability in stroke patients despite prolonged MCA mainstem occlusion., Material/methods: We retrospectively reviewed all stroke patients from our local registry with MCA mainstem occlusion after mechanical thrombectomy between November 2009 and October 2016. All patients underwent non-enhanced post-interventional cranial CT imaging (NCCT) and were classified according to 6 patterns of BG viability: complete: putamen (P) and globus pallidus (GP); partial: P or GP, and combination of complete or partial BG and/or adjacent white matter/cortical (WMC) viability. We compared viability patterns with respect to pre-interventional stroke imaging including NCCT, CT-angiography (CTA), CT perfusion (CTP); demographics, pre- and intra-procedural data and occurrence of post-procedural intracerebral hematoma (ICH). CTP imaging of the affected and contralateral BG-territories were obtained separately and CTA-collateral score (CS) was assessed., Results: A significant correlation between higher collateral score and viability of GP (OR = 1.949; p = .011), P (OR = 2.039, p = .011), and the combination of GP, P and WMC (OR = 2.767, p = .007) was revealed. Higher relative CBV ratio (rCBVR) was significantly associated with viability of the pattern GP + WMC (univariate: OR = 3.160, p = .014; multivariate: OR = 6.058; p = .021)., Conclusion: CTA collateral score and rCBVR were predictive for BG viability in stroke patients after successful MTE in prolonged complete MCA-mainstem and LSA occlusion., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Aims of the Study: Neurological impairment after resuscitated cardiac arrest (CA) remains a significant unmet medical need. Brain ischemia associated with CA and subsequent reperfusion is evident as two fundamentally different types of damage on neuropathological examination: frank necrosis (involving all cell types) and selective eosinophilic neuronal death (SEND). These types of damage are not only dissimilar in micromorphology, but also differently detectable with clinical brain imaging methods. In a previous study, SEND was reported in most patients surviving the initial CA. This study was undertaken to further characterize and map SEND in an expanded dataset., Methods: A cohort of 46 cases was included from an observational study on targeted temperature management (TTM) of resuscitated CA. Six brain and brain stem regions and 21 subregions were examined, and SEND severity was tested for correlation with time to ROSC. Representativity of all regions vis-à-vis global SEND was assessed, to investigate whether any particular region could be used as a "sentinel site" for overall damage., Results: The thalamus, the CA4 subregion of the hippocampus and the Purkinje cell layer of the cerebellum were the most severely affected subregions. Involvement of the hippocampus, cerebellum, cortex or basal ganglia indicated presence of SEND in other regions. There was a significant correlation between time to ROSC and SEND., Conclusion: There are regional differences in SEND distribution. Cases free of SEND in the hippocampus or basal ganglia are unlikely to have significant SEND in other regions, suggesting that these regions could be used as "sentinel sites" for global SEND in future studies., (Copyright © 2019. Published by Elsevier B.V.)

Post-traumatic striatocapsular infarction is extremely rare and has been described only within the vascular territory of the perforating arteries originating from the middle cerebral artery (MCA). We recently encountered a patient presenting with unilateral multifocal striatocapsular hemorrhagic infarctions following mild head injury. This 25-year-old female was admitted to our trauma center after a motorcycle accident. Initial brain computed tomography and magnetic resonance (MR) imaging showed multifocal acute hemorrhagic infarctions with a clustering in the right caudate head, anterior limb of internal capsule, and globus pallidus. MR angiography and digital subtraction angiography showed suspicious luminal irregularities of the lenticulostriate arteries of the right MCA. Vessel wall MR images (VWI) did neither indicate intramural hematoma nor wall enhancement in the right MCA, suggesting dissection. However, VWI showed the passages of each lenticulostriate artery supplying each infarction site. Therefore, based on both conventional images and VWI, we postulate that this patient's post-traumatic multifocal striatocapsular hemorrhagic infarctions were caused by damage to multiple lenticulostriate arteries.

Objective: With the increasing use of flow diversion as treatment for intracranial aneurysms, there is a concomitant increased vigilance in monitoring complications. The low porosity of flow diverters is concerning when the origins of vessels are covered, whether large circle of Willis branches or critical perforators. In this study, the authors report their experience with flow diverter coverage of the lenticulostriate vessels and evaluate their safety and outcomes., Methods: The authors retrospectively reviewed 5 institutional databases of all flow diversion cases from August 2012 to June 2018. Information regarding patient presentation, aneurysm location, treatment, and outcomes were recorded. Patients who were treated with flow diverters placed in the proximal middle cerebral artery (MCA), proximal anterior cerebral artery, or distal internal carotid artery leading to coverage of the medial and lateral lenticulostriate vessels were included. Clinical outcomes according to the modified Rankin Scale were reviewed. Univariate and multivariate analyses were performed to establish risk factors for lenticulostriate infarct., Results: Fifty-two patients were included in the analysis. Postprocedure cross-sectional images were available in 30 patients. Two patients experienced transient occlusion of the MCA during the procedure; one was asymptomatic, and the other had a clinical and radiographic ipsilateral internal capsule stroke. Five patients had transient symptoms without radiographic infarct in the lenticulostriate territory. Two patients experienced in-stent thrombosis, leading to clinical MCA infarcts (one in the ipsilateral caudate) after discontinuing antiplatelet therapy. Discontinuation of dual antiplatelet therapy prior to 6 months was the only variable that was significantly correlated with stroke outcome (p < 0.01, OR 0.3, 95% CI 0-0.43), and this significance persisted when controlled for other risk factors, including age, smoking status, and aneurysm location., Conclusions: The use and versatility of flow diversion is increasing, and safety data are continuing to accumulate. Here, the authors provide early data on the safety of covering lenticulostriate vessels with flow diverters. The authors concluded that the coverage of these perforators does not routinely lead to clinically significant ischemia when dual antiplatelet therapy is continued for 6 months. Further evaluation is needed in larger cohorts and with imaging follow-up as experience develops in using these devices in more distal circulation.

Type 1 diabetes is associated with slower psychomotor speed, but the neural basis of this relationship is not yet understood. The basal ganglia are a set of structures that are vulnerable to small vessel disease, particularly in individuals with type 1 diabetes. Thus, we examined the relationship between psychomotor speed and resting state resting cerebral blood flow in a sample of adults with diabetes onset during childhood (≤ 17 years of age). The sample included 77 patients (39 M, 38 F) with a mean age of 47.43 ± 5.72 years, age of onset at 8.50 ± 4.26 years, and duration of disease of 38.92 ± 4.18 years. Resting cerebral blood flow was quantified using arterial spin labeling. After covarying for sex, years of education and normalized gray matter volume, slower psychomotor speed was associated with lower cerebral blood flow in bilateral caudate nucleus-thalamus and a region in the superior frontal gyrus. These results suggest that the basal ganglia and frontal cortex may underlie slower psychomotor speed in individuals with type 1 diabetes.

Preeclampsia (PE), a dangerous hypertensive complication of pregnancy, is associated with widespread maternal vascular dysfunction. However, the effect of PE on the cerebral vasculature that can lead to stroke and cognitive decline is not well understood. We hypothesized that function of cortical parenchymal arterioles (PAs) would be impaired during PE. Using a high cholesterol diet to induce experimental PE in rats (ePE), we studied the function and structure of isolated and pressurized PAs supplying frontoparietal white matter (WM) tracts and cortex and compared to normal pregnant (Preg) and nonpregnant (Nonpreg) Sprague Dawley rats (n = 8/group). Myogenic reactivity and tone were similar between groups; however, constriction to intermediate-conductance calcium-activated potassium (IK) channel inhibition was diminished and dilation to inward-rectifying K + (K IR ) channel activation was impaired in PAs from ePE rats, suggesting altered ion channel function. Conducted vasodilation was significantly delayed in response to 12 mM KCl, but not 10 μM adenosine, in PAs from ePE rats versus Preg and Nonpreg rats (940 ± 300 ms vs. 70 ± 50 ms and 370 ± 90 ms; p < 0.05). Overall, dysfunction of PAs supplying frontoparietal WM and gray matter was present in ePE. If persistent these changes could potentiate neuronal injury that over time could contribute to WM lesions and early-onset cognitive decline., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Ictal automatism with preserved responsiveness (APR) has been reported, particularly in nondominant temporal lobe epilepsy (TLE), but its pathophysiology remains poorly understood. This study sought to investigate the relationship between APRs and increased cerebral blood flow (CBF) using ictal single photon emission computed tomography (SPECT) in TLE. Forty-seven subjects with right mesial TLE (15 with and 32 without APR) were enrolled. Patients with APR (APR+) were subdivided into four groups according to degree of responsiveness during seizures. Cerebral blood flow changes during these seizures were semiquantitatively assessed by subtraction ictal SPECT coregistered to MRI (SISCOM). Hyperperfusion in temporal regions did not vary significantly between the APR+ and APR- groups. Cerebral blood flow changes in the frontal area, insula, cingulum, and occipital area were also nonsignificant. However, hyperperfusion in the ipsilateral parietal areas was more frequent in the APR- group than in the APR+ group. Furthermore, hyperperfusion of the contralateral basal ganglia showed an inclination to be more common in the APR- group, but without statistical significance. The study suggested that the involvement of the parietal association cortex during seizure may play an important role in ictal loss of consciousness in TLE. Further studies will be needed to elucidate the pathophysiology of changes in consciousness during temporal lobe seizures., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Hematoma expansion (HE) is an independent predictor of poor outcome and secondary neurological deterioration in intracerebral hemorrhage (ICH) and is associated with high morbidity and mortality. Noncontrast computed tomography (NCCT) may identify the sites of active extravasation. Therefore, we have attempted to (1) devise a reliable and easy-to-use prediction score to predict the risk of HE in ICH and (2) validate the accuracy of this grading system and perform an independent analysis of HE predictors. We included patients in whom an intracerebral hemorrhage (ICH) occurred in the basal ganglia between Jan. 2015 and Jan. 2018. These patients had undergone a baseline CT scan at Qinghai Provincial People's Hospital within 24 hours after the onset of ICH symptoms. Two observers independently assessed the presence of the island sign, blend sign, or swirl sign on an NCCT scan during patient selection. Patients underwent a baseline NCCT scan and 24-hour NCCT follow-up for analysis of HE. The accuracy of this grading system was assessed. Independent predictors of HE were identified using multivariable regression. Of 266 patients with ICH, 61 (22.93%) presented with the island sign, 63 (23.68%) presented with the blend sign, and 50 (18.80%) presented with the swirl sign. The overall incidence of HE was 37.22% (99/266). Of 125 patients (46.99%) who underwent a baseline CT scan within 6 hours of onset, 141 (53.01%) underwent a scan in 6-24 hours. Multivariable logistic regression analysis identified the hematoma volume (OR, 0.974; P = 0.042), intraventricular hemorrhage (IVH) extension (OR, 3.225; P = 0.003), time from onset to the baseline CT scan (OR, 0.986; P < 0.001), and anticoagulant use or an international normalized ratio (INR) > 1.5 (OR, 3.362; P = 0.006) as closely associated with HE. In conclusion, the grading system demonstrated reliable accuracy at predicting HE. The grading system demonstrated acceptable accuracy in an independent single-institution study. The role of the grading system in predicting HE and poor outcome in patients with ICH is significant. NCCT imaging markers may serve as key markers for HE prediction.

Purpose: Abnormal brain perfusion is a critical mechanism in neonatal brain injury. The aim of the present study was to compare Cerebral Blood Flow (CBF) evaluated with ASL MRI in three groups of neonates: preterms without brain lesions on MRI (PN), preterms with periventricular white matter lesions (PNp) and term neonates with normal MRI (TN). The correlation between CBF and clinical outcome was explored., Materials and Methods: The institutional review board approved this prospective study and waived informed consent. The perfusion ASL data from 49 consecutive preterm neonates (PN) studied at term-equivalent age and 15 TN were evaluated. Statistically significant differences in gray matter CBF were evaluated by using a linear mixed-model analysis and Mann-Whitney U test. Logistic regression analysis was used to assess the relation between CBF and neuromotor outcome at 12 months., Results: Comparison of means indicated that the CBF of the whole brain were significantly higher in PN compared to TN ( P  = 0.011). This difference remained significant when considering the frontal ( P  = 0.038), parietal ( P  = 0.002), temporal ( P  = 0.030), occipital ( P  = 0.041) and cerebellar ( P  = 0.010) gray matter. In the PN group, lower CBF in basal ganglia was associated with a worse neuromotor outcome ( P  = 0.012)., Conclusions: ASL MRI demonstrated differences in brain perfusion of the basal ganglia between PN and TN. In PN, a positive correlation between CBF and neuromotor outcome was demonstrated in this area.

Background and Objective: Recent studies suggest perivascular spaces are a marker of small vessel disease, blood-brain barrier permeability, and inflammation, but little is known about their risk factors and associations with peripheral blood markers., Materials and Methods: In prospectively recruited patients with recent minor ischemic stroke, we investigated the influence of age, sex, hypertension, diabetes, and smoking on the severity of perivascular spaces in the basal ganglia seen on T2-weighted magnetic resonance imaging. We assessed plasma markers of endothelial function (von Willebrand factor, intracellular adhesion molecule-1), inflammation (interleukin-6, tumor necrosis factor-alpha, C-reactive protein), and thrombosis (fibrinogen, prothrombin fragments 1 + 2, thrombin-antithrombin complex, tissue plasminogen activator, D-dimer). We used a validated semi-automated method to measure basal ganglia perivascular spaces count and volume. We tested uni- and multivariable associations between blood markers and basal ganglia perivascular spaces count and volume., Findings: In 100 patients (median age: 67 years, range: 37-92), on adjusted analysis, basal ganglia perivascular spaces count was associated with age (r = .117, P = .003) and hypertension (r = 2.225, P = .013). On multivariable linear regression, adjusted for age, sex, hypertension, smoking and diabetes, reduced von Willebrand factor was associated with increased basal ganglia perivascular spaces count (r = -.025, P = .032)., Conclusion: The association of increased basal ganglia perivascular spaces count with reduced von Willebrand factor is novel. As von Willebrand factor may promote cerebral endothelial integrity, insufficient von Willebrand factor is consistent with dysfunctional cerebral endothelium and increased basal ganglia perivascular spaces in cerebral small vessel disease. Quantitative perivascular spaces measurement may increase sensitivity to detect cerebral endothelial dysfunction., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The preterm brain is susceptible to changes in blood flow. Using power Doppler images, digital imaging techniques have been developed to measure the total amount of blood flow in a defined area, giving the index: fractional moving blood volume (FMBV). The aim of this study was to investigate temporal changes in basal ganglia perfusion during the transitional period after birth., Methods: Twenty-four preterm infants were examined with serial cranial ultrasounds at four time points during the first 48 h of life. FMBV was calculated using power Doppler images at each time point., Results: All infants had analyzable data and FMBV was successfully calculated at all time points. Twenty-three of the 24 infants had an increasing trend in FMBV over time. The median FMBV increased from 17% at 6 h to 25% at 48 h. One-way repeated measures ANOVA showed a significant increase in values at P < 0.001 at each of the four time points., Conclusion: We have demonstrated changes in basal ganglia blood flow as the cerebral circulation adapts to extrauterine life. With further investigation, this technique may be useful in the assessment of preterm circulatory adaptation, either alone or in conjunction with other modes of evaluating cerebral blood flow.

Cerebral proliferative angiopathy (CPA), which is characterized by diffuse vascular abnormalities with intermingled normal brain parenchyma, is a rare clinical entity distinct from classical cerebral arteriovenous malformations. Its pathology at initial state and subsequent course of progression has totally been undetermined. We herein presented a case of a child who was initially diagnosed with deep-seated arteriovenous fistula (AVF), and ultimately developed symptomatic CPA-like vascular lesion over a long period of clinical follow-up. A 7-month-old boy was incidentally found to have an AVF in the right basal ganglia and conservatively followed up. Serial magnetic resonance angiograms revealed the gradual proliferation and enlargement of pial and medullary vessels surrounding the AVF. Seven years later, he had a transient ischemic attack followed by intraventricular hemorrhage. A catheter angiogram showed a diffuse large vascular malformation composed of 2 distinct structures, including AVF in the right basal ganglia and the surrounding proliferated pial and medullary arteries in the right hemisphere. Single-photon emission computed tomography with N-isopropyl[123I]-p-iodoamphetamine revealed apparent hemodynamic compromise on the right hemisphere. Targeted embolization of the pseudoaneurysm originating from the right A1 perforator was performed to prevent rebleeding without complications. The patient had no further cerebrovascular events. Perinidal hypoperfusion induced by a deep-seated AVF could be one of the underlying pathologies of progressive angiogenic activity. This is the first case showing the development of abnormal hemispheric vascular networks mimicking CPA, which offers insight into the pathogenesis of this new entity., (Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Recent studies have found long-range temporal correlations (LRTC) of neuronal oscillation under different physiological and pathological state. In this paper we aimed to explore the temporal correlations of broadband neuronal oscillation in poststroke depression. Resting state EEGs of 16 electrodes in 16 poststroke depression (PSD), 18 poststroke non-depression (PSND) and 18 healthy control (HC) subjects were analyzed by means of detrended fluctuation analysis (DFA), a quantitative measurement of LRTC. The results indicated that LRTC of broadband oscillation in PSD subjects was still preserved and had similar spatial distribution to non-depression subjects, but attenuated especially in left hemisphere and frontal and posterior temporal regions of right hemisphere. Moreover, a linear correlation between the severity of psychiatric symptoms and attenuation of LRTC was observed in stroke subjects. ROC curves indicated a high discriminating ability of scaling exponents in prefrontal regions distinguishing PSD from PSND, suggesting the feasibility for LRTC as assessment indicators to PSD.

Objectives: Pain disability is a major impediment to fibromyalgia (FM) patients' quality of life. Neuroimaging studies have demonstrated abnormal pain processing in FM. However, it is not known whether there are brain abnormalities linked to pain disability. Understanding neural correlates of pain disability in FM, independent from pain intensity, could provide a framework to guide future more efficient therapy strategies to improve patients' functional ability., Methods: We used arterial spin labeling to image cerebral blood flow (CBF) in 23 FM patients and 16 controls. Functional connectivity was also estimated using blood oxygenation level-dependent imaging to further investigate the possible underpinnings of the observed CBF changes., Results: Among patients, CBF in the basal ganglia correlated negatively with pain disability index and positively with the overall impact of FM (Fibromyalgia Impact Questionnaire) but did not correlate with pain intensity. Whole-brain analysis revealed no CBF differences between the 2 groups; however, post hoc analysis in the basal ganglia showed CBF reductions mainly in the right putamen and right lateral globus pallidus in patients, likely reflecting the negative correlation with the pain disability index. However, the connectivity of the corresponding corticobasal ganglia-thalamus loop, that is, motor network (the connection between supplementary motor area, putamen, and thalamus) remained intact., Discussion: Basal ganglia perfusion reflects long-term symptoms, including somatic and psychological components of FM rather than pain intensity. These CBF findings may reflect differences in behavioral and psychological responses between patients.

Background: Besides motor function, the basal ganglia have been implicated in feedback learning. In patients with chronic basal ganglia infarcts, deficits in reward-based reversal learning have previously been described., Methods: We re-examined the acquisition and reversal of stimulus-stimulus-reward associations and acquired equivalence in eleven patients with acute basal ganglia stroke (8 men, 3 women; 57.8±13.3 years), whose performance was compared eleven healthy subjects of comparable age, sex distribution and education, who were recruited outside the hospital. Eleven hospitalized patients with a similar vascular risk profile as the stroke patients but without stroke history served as clinical control group., Results: In a neuropsychological assessment 7±3 days post-stroke, verbal and spatial short-term and working memory and inhibition control did not differ between groups. Compared with healthy subjects, control patients with vascular risk factors exhibited significantly reduced performance in the reversal phase (F[2,30] = 3.47; p = 0.044; post-hoc comparison between risk factor controls and healthy controls: p = 0.030), but not the acquisition phase (F[2,30] = 1.01; p = 0.376) and the acquired equivalence (F[2,30] = 1.04; p = 0.367) tasks. In all tasks, the performance of vascular risk factor patients closely resembled that of basal ganglia stroke patients. Correlation studies revealed a significant association of the number of vascular risk factors with reversal learning (r = -0.33, p = 0.012), but not acquisition learning (r = -0.20, p = 0.121) or acquired equivalence (r = -0.22, p = 0.096)., Conclusions: The previously reported impairment of reward-based learning may be attributed to vascular risk factors and associated diseases, which are enriched in stroke patients. This study emphasizes the necessity of appropriate control subjects in cognition studies.

Flat-detector CT perfusion (FD-CTP) imaging has demonstrated efficacy in qualitatively accessing the penumbra in acute stroke equivalent to that of magnetic resonance perfusion (MRP). The aim of our study was to evaluate the feasibility of quantifying oligemia in the brain in patients with carotid stenosis.Ten patients with unilateral carotid stenosis of >70% were included. All MRPs and FD-CTPs were performed before stenting. Region-of-interests (ROIs) including middle cerebral artery territory at basal ganglia level on both stenotic and contralateral sides were used for quantitative analysis. Relative time to peak (rTTP) was defined as TTP of the stenotic side divided by TTP of the contralateral side, and so as relative cerebral blood volume (rCBV), relative mean transit time (rMTT), and relative cerebral blood flow (rCBF). Absolute and relative TTP, CBV, MTT, CBF between two modalities were compared.For absolute quantitative analysis, the correlation of TTP was highest (r = 0.56), followed by CBV (r = 0.47), MTT (r = 0.47), and CBF (r = 0.43); for relative quantitative analysis, rCBF was the highest (r = 0.79), followed by rTTP (r = 0.75) and rCBV (r = 0.50).We confirmed that relative quantitative assessment of FD-CTP is feasible in chronic ischemic disease. Absolute quantitative measurements between MRP and FD-CTP only expressed moderate correlations. Optimization of acquisitions and algorithms is warranted to achieve better quantification.

Objective: Animal models suggest that the development of psychosis involves hyperactivity in the hippocampus that drives increased activity in the midbrain and basal ganglia. The authors examined this hypothesis by measuring resting perfusion in the hippocampus, basal ganglia, and midbrain in people at high risk of psychosis., Method: Pseudo-continuous arterial spin labeling imaging was used to measure resting regional cerebral blood flow (rCBF) in 52 individuals at ultra-high risk for psychosis and in 27 healthy volunteers. The severity of psychotic symptoms was assessed using the Comprehensive Assessment of At-Risk Mental States. The ultra-high-risk subjects were reassessed after a mean of 17 months, using the same measures as at baseline., Results: At baseline, relative to healthy volunteers, ultra-high-risk subjects showed elevated rCBF in the hippocampus, basal ganglia, and midbrain. In the ultra-high-risk sample overall, at follow-up, symptomatic improvement and reduced rCBF in the hippocampus and ventral striatum were observed. Subjects whose symptoms had resolved such that they no longer met ultra-high-risk criteria showed a longitudinal reduction in left hippocampal rCBF that was not evident in subjects who remained in a high-risk state or had become psychotic., Conclusions: A high risk for psychosis was associated with increased resting activity in the hippocampus, midbrain, and basal ganglia. Subsequent resolution of the high-risk state was linked to a normalization of activity in these regions. These findings are consistent with animal models that propose that psychotic symptoms may be generated when hippocampal hyperactivity drives hyperactivity in regions involved in subcortical dopamine signaling.

Although the general vascular supply of the basal ganglia and internal capsule is well known, precise data are lacking regarding the variations of the vascular territories in the two regions. Twelve hemispheres were studied following an injection of coloured ink into the main cerebral arteries, namely the anterior cerebral (ACA), middle cerebral (MCA), anterior choroidal (AChA) and posterior cerebral artery (PCA). Serial sections of the injected hemispheres were taken in the axial or coronal plane. In 75% of the hemispheres, ACA perforators were seen to supply the inferomedial part of the head of the caudate nucleus and the anterior limb of the internal capsule, as well as the anterior and inferior portions of the putamen and globus pallidus. The MCA vessels perfused the superolateral part of the head and body of the caudate nucleus, the superior part of the entire internal capsule, most of the putamen and part of the globus pallidus. The AChA perforators perfused the medial segment of the globus pallidus, the inferior part of the posterior limb, the retrolenticular and sublenticular portions of the internal capsule, and occasionally its genu. The same segment of the globus pallidus and the inferior part of the genu of the internal capsule were most likely supplied by the perforators of the internal carotid artery. A predominance of ACA territory was noticed in one specimen (8.33%) and a predominance of MCA territory in two specimens (16.67%). The obtained anatomical data may help radiologic determination of perforators involved in ischemic events, as well as a better understanding of the neurological deficits in the same events., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Regional changes in cerebral blood flow and perfusion are implicated in the pathogenesis of adverse neurological events that lead to death and severe disability in the newborn infant. The basal ganglia, in particular, are extremely sensitive to acute hypoxia in the perinatal period, but normal perfusion to this area is unknown., Objectives: To establish a reference range for regional basal ganglia perfusion using fractional moving blood volume (FMBV) as an index., Methods: Head ultrasounds were performed on neonates from 25 to 41 weeks' gestation. Power Doppler images were obtained from a pre-specified coronal plane. FMBV was calculated offline after selecting the basal ganglia as a region of interest. The average of five calculations was considered to be representative of the regional perfusion for each neonate. The data were analysed, and a neonatal reference range was defined., Results: 124 neonates were included in the study, and all had analysable data. The mean FMBV was 28.8% (±9.6) with a reference range defined as 10-48%. The mean FMBV for neonates <32 weeks', 32-35 weeks' and >35 weeks' gestation were 29.4% (±7.8), 29.2% (±11.0) and 27.4% (±9.7), respectively. Analysis of variance showed no significant difference between neonates based on gestation., Conclusions: We have successfully used the index FMBV to define a reference range for perfusion in the basal ganglia. These data can be used as a reference for subsequent studies that evaluate basal ganglia perfusion in pathological conditions., (© 2015 S. Karger AG, Basel.)

Purpose: Hyperintense vessels (HVs) on fluid-attenuated inversion recovery (FLAIR) imaging are associated with the leptomeningeal collateral circulation in cases of arterial occlusive lesions. Nevertheless, the relationship between HVs on FLAIR imaging and arterial circulation time (ACT) on cerebral angiography has not been defined., Methods: We analyzed images of 11 patients with acute occlusion of the distal internal carotid artery or proximal middle cerebral artery and calculated the difference in ACT (DACT) between infarcted and normal hemispheres. ACT was defined as the time interval from the initial opacification of the ipsilateral or contralateral cavernous internal carotid artery to the late arterial phase of the carotid artery territories. We scored HVs on FLAIR imaging using a modified Alberta Stroke Program Early Computerized Tomography Score (ASPECTS) and determined collateral circulation by grading collateral flow., Results: We detected HVs on FLAIR images in 10 patients (median score, 4; range, 0 to 6). Comparison of infarcted and normal hemispheres demonstrated absent or subtle HVs on FLAIR imaging when the DACT was too short (7.98 s) and prominent HVs with moderate DACT (2 to 5 s). The score of HVs on FLAIR was estimated well by DACT using a quadratic regression model (R(2) = 0.602) and better than by grading collateral flow (R(2) = 0.256)., Conclusion: In cases of large arterial occlusion, the hyperintensity of vessels on FLAIR images may be dependent on arterial circulation time via retrograde filling of the leptomeningeal collateral circulation.

Background: Cerebral microvascular abnormality is frequently associated with lacunar and subcortical ischemic lesions. We performed acute and follow-up CT perfusion scans over the first 3 months after ischemic stroke to investigate disturbances of the blood-brain barrier (BBB) and cerebral perfusion in patients with lacunar/subcortical lesions compared to those with cortical lesions alone., Methods: Thirty-one patients with lacunar/subcortical infarct (n = 14) or with cortical large vessel infarct (n = 17) were recruited and underwent a CT perfusion study at admission, 24 h, 7 days and 3 months after stroke using a two-phase imaging protocol. Functional maps of BBB permeability surface area product (BBB-PS), cerebral blood flow (CBF) and blood volume (CBV) at follow-up were co-registered with those at admission, and the measurements in non-infarcted ipsilateral basal ganglia and thalamus were compared within each group and between the two groups., Results: For the lacunar/subcortical group, BBB-PS within non-infarcted ipsilateral basal ganglia and thalamus peaked at day 7 compared to all other time points, and was significantly higher than the cortical group at day 7 and month 3. The CBF and CBV in the same region were significantly lower at admission and transient hyperemia was seen at day 7 in the lacunar/subcortical group., Conclusion: Disturbed BBB-PS and compromised cerebral perfusion over the first 3 months post stroke were shown in the non-infarcted basal ganglia and thalamus of lacunar/subcortical stroke using CT perfusion. Future studies are required to elucidate the relationship of post-stroke BBB disturbances to chronic cognitive impairment.

Background: Neurointerventionalists do not agree about the optimal imaging protocol when evaluating patients with acute stroke for potential endovascular revascularization. Preintervention cerebrovascular blood volume (CBV) has been shown to predict outcomes in patients undergoing intra-arterial stroke therapies., Objective: To determine whether CBV can predict hemorrhagic transformation and clinical outcomes in patients selected for endovascular therapy for acute ischemic middle cerebral artery (MCA) stroke using a CT perfusion (CTP)-based imaging protocol., Methods: We retrospectively reviewed cases of acute ischemic stroke due to MCA M1 segment occlusion and correlated favorable clinical outcomes (modified Rankin scale (mRS) ≤2) and radiographic outcomes with preintervention CBV values. All patients underwent whole-brain (320-detector-row) CTP imaging, and absolute CBV values of the affected and contralateral MCA territories were obtained separately for the cortical and basal ganglia regions., Results: Relative CBV (rCBV) of the MCA cortical regions was significantly lower in patients with poor clinical outcomes than in those with favorable clinical outcomes (0.87±0.21 vs 1.02±0.09, p=0.0003), and a negative correlation was found between rCBV values and mRS score severity. rCBV of the basal ganglia region was significantly lower in patients with hemorrhagic infarction (p=0.004) and parenchymal hematoma (p=0.04) than in those without hemorrhagic transformation., Conclusions: We found that cortical CBV loss is predictive of poor clinical outcomes, whereas basal ganglia CBV loss is predictive of hemorrhagic transformation but without translation into poor clinical outcomes. Our study findings support published results of baseline preintervention CBV as a predictor of outcomes in patients undergoing intra-arterial stroke therapies., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objectives: Recent studies indicate an interest in early infarct assessment, mainly using post-interventional perfusion imaging. This work evaluated two specific angiographic signs for infarct prediction in the basal ganglia immediately after successful mechanical intra-arterial thrombectomy., Methods: In this retrospective study, 57 consecutive patients (mean ± SD age 67 ± 15 years) with acute occlusion of the proximal anterior circulation who underwent mechanical thrombectomy of the M1 segment of the middle cerebral artery were included. Two separate angiographic signs, early venous drainage and capillary blush, were identified and analysed regarding their statistical significance for infarct prediction within the basal ganglia., Results: Four patients were excluded due to parenchymal haemorrhage. Forty-four of 53 patients developed infarction of the basal ganglia. Sensitivity/specificity were 93%/27%, respectively, for the capillary blush sign and 88%/63%, respectively, for the early venous drainage sign. Combining both signs increased the sensitivity and specificity to 88% and 81%, respectively, and increased the positive predictive value to 95%., Conclusions: Both angiographic signs seem to predict the irreversible damage of tissue in the basal ganglia reliably despite successful recanalization of the middle cerebral artery in patients with ischaemic stroke., Key Points: • Evaluation of success in neurointerventional procedures is mainly based on recanalization rates. • Two separate angiographic signs can predict infarction immediately after proximal MCA recanalization. • Combining both signs increases their specificity.

Background: Virchow-Robin spaces (VRS) are brain perivascular spaces containing perforating arteries. Although enlarged VRS are associated with various disorders such as Alzheimer's disease, cerebrovascular disease, and head trauma, their functional role remains unclear. Using highly fluid-sensitive magnetic resonance imaging (MRI) sequences, fine morphological features of VRS and their relevance to idiopathic normal pressure hydrocephalus (iNPH) were investigated., Methods: Three-dimensional constructive interference in steady state (3D-CISS) on 3 Tesla MRI was applied to 29 individuals. The morphology and number of VRS in the basal ganglia and white matter were compared between 20 patients with iNPH and nine age-matched controls. The VRS number per hemisphere was classified into three grades: few, moderate, and abundant., Results: Virchow-Robin spaces in the basal ganglia were curved, irregularly sized and shaped, and communicated with the cerebrospinal fluid in the subarachnoid space; they contained perforating arteries. VRS in the white matter were straight, smooth, homogeneously sized and shaped, and did not penetrate the cortex. Arteries were not seen in VRS of the white matter. White matter VRS were sparse in patients with iNPH. In contrast, basal ganglia VRS positively correlated with age. Postoperatively after shunt surgery, VRS in the white matter were mildly decreased in diameter, but not in number. No significant changes were noted in basal ganglia VRS., Conclusions: The present study revealed different morphological features of VRS in the basal ganglia and white matter. VRS in the basal ganglia were seen as genuine perivascular spaces; while neither communication with subarachnoid spaces nor arteries were seen in white matter VRS, even by 3D-CISS sequences and high-resolution magnetic resonance angiography on 3T-MRI. White matter VRS were sparse in patients with iNPH and they were mildly decreased in diameter, but did not change in number after surgery. At present, it remains unclear whether the white matter VRS are dilated interstitial fluid spaces or cerebral amyloid angiopathy, or both. Further studies are necessary to elucidate the functional role of VRS in normal subjects and patients with iNPH.

Marked changes in brain physiology and structure take place between childhood and adulthood, including changes in functional connectivity and changes in the balance between main excitatory and inhibitory neurotransmitters glutamate (Glu) and GABA. The balance of these neurotransmitters is thought to underlie neural activity in general and functional connectivity networks in particular, but so far no studies have investigated the relationship between human development related differences in these neurotransmitters and concomitant changes in functional connectivity. GABA+/H2O and Glu/H2O levels were acquired in a group of healthy children, adolescents, and adults in a subcortical (basal ganglia) region, as well as in a frontal region in adolescents and adults. Our results showed higher GABA+/Glu with age in both the subcortical and the frontal voxel, which were differentially associated with significantly lower Glu/H2O with age in the subcortical voxel and by significantly higher GABA+/H2O with age in the frontal voxel. Using a seed-to-voxel analysis, we were further able to show that functional connectivity between the putamen (seed) and other subcortical structures was lower with age. Lower subcortical Glu/H2O with age mediated the lower connectivity in the dorsal putamen. Based on these results, and the potential role of Glu in synaptic pruning, we suggest that lower Glu mediates a reduction of local connectivity during human development., (Copyright © 2015 the authors 0270-6474/15/358433-09$15.00/0.)

The prefrontal cortex and the basal ganglia interact to selectively gate a desired action. Recent studies have shown that this selective gating mechanism of the basal ganglia extends to the domain of attention. Here, we investigate the nature of this action-like gating mechanism for attention using a spatial attention-switching paradigm in combination with functional neuroimaging and dynamic causal modeling. We show that the basal ganglia guide attention by focally releasing inhibition of task-relevant representations, while simultaneously inhibiting task-irrelevant representations by selectively modulating prefrontal top-down connections. These results strengthen and specify the role of the basal ganglia in attention. Moreover, our findings have implications for psychological theorizing by suggesting that inhibition of unattended sensory regions is not only a consequence of mutual suppression, but is an active process, subserved by the basal ganglia., (© The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

We were interested in motor performance gain after unilateral hand motor training and associated changes of cerebral and cerebellar movement representation tested with functional magnetic resonance imaging (fMRI) before and after training. Therefore, we trained the left hand of strongly right-handed healthy participants with a comprehensive training (arm ability training, AAT) over two weeks. Motor performance was tested for the trained and non-trained hand before and after the training period. Functional imaging was performed for the trained and the non-trained hand separately and comprised force modulation with the fist, sequential finger movements and a fast writing task. After the training period the performance gain of tapping movements was comparable for both hand sides, whereas the motor performance for writing showed a higher training effect for the trained hand. fMRI showed a reduction of activation in supplementary motor, dorsolateral prefrontal cortex, parietal cortical areas and lateral cerebellar areas during sequential finger movements over time. During left hand writing lateral cerebellar hemisphere also showed reduced activation, while activation of the anterior cerebellar hemisphere was increased. An initially high anterior cerebellar activation magnitude was a predictive value for high training outcome of finger tapping and visual guided movements. During the force modulation task we found increased activation in the striate. Overall, a comprehensive long-term training of the less skillful hand in healthy participants resulted in relevant motor performance improvements, as well as an intermanual learning transfer differently pronounced for the type of movement tested. Whereas cortical motor area activation decreased over time, cerebellar anterior hemisphere and striatum activity seem to represent increasing resources after long-term motor training., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A 73-year-old man presented with continuous hemichoreic movement of right arm and leg and with dyskinesia in his tongue. Magnetic resonance image (MRI) showed no ischemic lesion within the basal ganglia, but magnetic resonance angiography (MRA) and carotid duplex ultrasonography showed the left internal carotid occlusion and 80% stenosis in the right common carotid artery. Tc-99m-ECD-SPECT showed hypoperfusion of the frontal lobe, temporal lobe, parietal lobe, basal ganglia and thalamus. A trial of haloperidol had no effect; therefore, the right carotid artery stenting was performed. Hypoperfusion in the left internal carotid artery area was improved by cross flow from the right side, and his hemichorea gradually improved. This result supports the notion that hypoperfusion-related hemichorea may occur, even in the absence of cerebral ischemia.

Purpose: Hyperperfusion may be related to outcome in neonates with hypoxic-ischemic encephalopathy (HIE). The purpose of this study was to evaluate whether arterial spin labelling (ASL) perfusion is associated with outcome in neonates with HIE and to compare the predictive value of ASL MRI to known MRI predictive markers., Methods: Twenty-eight neonates diagnosed with HIE and assessed with MR imaging (conventional MRI, diffusion-weighted MRI, MR spectroscopy [MRS], and ASL MRI) were included. Perfusion in the basal ganglia and thalami was measured. Outcome at 9 or 18 months of age was scored as either adverse (death or cerebral palsy) or favourable., Results: The median (range) perfusion in the basal ganglia and thalami (BGT) was 63 (28-108) ml/100 g/min in the neonates with adverse outcome and 28 (12-51) ml/100 g/min in the infants with favourable outcome (p < 0.01). The area-under-the-curve was 0.92 for ASL MRI, 0.97 for MRI score, 0.96 for Lac/NAA and 0.92 for ADC in the BGT. The combination of Lac/NAA and ASL MRI results was the best predictor of outcome (r(2) = 0.86, p < 0.001)., Conclusion: Higher ASL perfusion values in neonates with HIE are associated with a worse neurodevelopmental outcome. A combination of the MRS and ASL MRI information is the best predictor of outcome., Key Points: • Arterial spin labelling MRI can predict outcome in neonates with hypoxic-ischemic encephalopathy • Basal ganglia and thalami perfusion is higher in neonates with adverse outcome • Arterial spin labelling complements known MRI parameters in the prediction of outcome • The combined information of ASL and MRS measurements is the best predictor of outcome.

Recent symptom provocation studies that compared patients suffering from dental phobia with healthy controls identified hyperactivation of basal ganglia structures, but none have assessed striatal functional connectivity. We reanalyzed data from a previous functional magnetic resonance imaging study on dental phobia. Patients (20 men, 25 women) and healthy controls (18 men, 23 women) had been exposed to pictures showing dental treatment, and neutral contents. We conducted connectivity analyses via psychophysiological interactions (PPIs). Relative to non-phobic controls, the patients showed decreased connectivity between prefrontal and basal ganglia regions. Moreover, the clinical group was characterized by increased internal basal ganglia connectivity, which was more pronounced in female compared with male patients. This study provides first evidence for an altered information flow within a fronto-striatal network in dentophobic individuals during visual symptom provocation, which can be considered a neuromarker of this disorder., (© The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.)

Background: The insular perforating arteries originate from the middle cerebral artery. They have only been very partially described up to now. In the literature, they come from the M2 segment and three types are listed: the short, medium and long perforators. The first two types supply the claustrum as well as the external and extreme capsules., Objective: We describe the anatomy of long perforating insular arteries and their arterial contribution to the main white matter bundles of the oval center of Vieussens., Materials and Method: Twenty adult cadaveric hemispheres were studied after perfusion of the arteries and veins with colored latex. The arteries were dissected and photographed under an operating microscope., Results: The long insular perforating arteries come from the M2 segment or from the junction of the M2 and M3 segments and sometimes from the M3 segment. They often perforate the insular cortex on the top of the posterior short insular gyrus and the insular long gyri, or in the superior peri-insular sulcus, before coming together in the oval center. At this level, they give arterial contribution to the main white matter bundles such as corticospinal and corticonuclear tracts for motricity, and the arcuate fasciculus and the occipitofrontal tract for language in the dominant hemisphere., Conclusion: These perforating arteries have to be carefully respected during insular surgery to avoid neurologic weakness.

Aim: The aim of this study was to investigate the association of infarct location with post-stroke executive dysfunction., Methods: One hundred seventy-seven patients hospitalized with acute infarction were enrolled. General information and NIHSS score at admission were recorded. The infarct site was recorded from magnetic resonance T2-W1 and FLAIR images, and the extent of white matter disease was assessed using the Fazekas score. Seven days after symptoms, executive function was assessed using the validated Chinese version of Mattis Dementia Rating Scale (MDRS) Initiation/Perseveration (I/P) [MDRS I/P]., Results: The average MDRS I/P score of the 177 infarction patients was 24.16 ± 5.21, considerably lower than the average score (32.7 ± 3.1) of a control group of normal individuals. Patients with infarcts in the corona radiata or basal ganglia had significantly lower MDRS I/P scores that those without infarcts at these locations. The number of infarcts in the basal ganglia was also significantly associated with low MDRS I/P scores. Male gender and low NIHSS score were significantly associated with low MDRS I/P score, and high-density lipoprotein cholesterol was significantly associated with high MDRS I/P score. The number of infarcts in areas other than the basal ganglia as well as corona radiata and the extent of white matter disease had no influence on this score., Conclusions: The number of infarcts in the basal ganglia corona radiata, low NIHSS score, and male gender are significantly and independently related to poor executive function (that is, low MDRS I/P score) after acute infarct.

Background and Purpose: CT perfusion scans are often used in acute stroke evaluations. We aimed to assess the outcome of areas of basal ganglia hyperperfusion on CTP in patients with acute ischemic stroke., Materials and Methods: We retrospectively reviewed the medical records and brain imaging of 139 patients presenting with acute stroke who underwent CTP for consideration of endovascular recanalization. Hyperperfusion was assessed qualitatively and defined as a matched region of increased cerebral blood flow and cerebral blood volume. CTA was used to locate arterial occlusion. Follow-up imaging was used to determine whether regions of hyperperfusion at baseline became infarcted or developed hemorrhage. Angiographic imaging was assessed to determine the presence or absence of early venous opacification., Results: Six patients (4.3%) demonstrated hyperperfusion in the basal ganglia of the affected side (4 in the lenticular nucleus and 2 in the caudate). In all cases, the area of hyperperfusion ultimately proved to be infarcted. All patients had received intravenous thrombolysis before the CTP. CTA at the time of CTP showed middle or distal M1 occlusion but patency of the proximal M1 and A1 segments. Intracranial hemorrhage was noted in 2 of these 6 patients at follow-up., Conclusions: Acute basal ganglia hyperperfusion in patients with stroke may indicate nonviable parenchyma and risk of hemorrhagic conversion., (© 2014 by American Journal of Neuroradiology.)

Objectives: The objectives of this study were to explore the possibilities of 7 T brain magnetic resonance imaging to visualize perivascular spaces (PVS) and to depict their related blood vessels., Materials and Methods: Five subjects aged 19 to 27 years and 5 subjects aged 51 to 72 years were scanned. High-resolution 3-dimensional T1-, T2-, as well as T2*-weighted sequences and time-of-flight angiography were used for the visualization of PVS, veins, and perforating arteries. Three extra subjects were scanned with a 2-dimensional time-of-flight sequence tailored to visualize small arteries and veins in the semioval center. The anatomy of PVS and their spatial relation with blood vessels were examined. The number and size of PVS in the semioval center were compared between the 2 groups., Results: In the basal ganglia, PVS were connected to the basal cisterns. Prominent dilations were observed in these PVS around the lower end of the putamen. From here, they ran upward and frequently showed caliber changes along their track. In the semioval center, smoothly shaped PVS started a few millimeters below the cortex, converged and tapered toward the ventricles, and ended 1 to 2 cm before the ventricle wall. Perivascular spaces correlated spatially with lenticulostriate arteries and with perforating arteries in the semioval center, but not with veins. The mean (SD) number of PVS was larger in the older subjects (55 [14]) than in the younger subjects (22 [11]), (P = 0.004). No difference in PVS diameter was observed., Conclusions: Seven-tesla magnetic resonance imaging offers detailed 3-dimensional visualization of PVS, their morphological features, and their related perforating arteries. This may offer new opportunities to study the role of PVS in ageing and cerebral small vessel disease.

The ventral striatum (VStr) integrates mesolimbic dopaminergic and corticolimbic glutamatergic afferents and forms an essential component of the neural circuitry regulating impulsive behaviour. This structure represents a primary target of psychostimulant medication, the first-choice treatment for attention-deficit/hyperactivity disorder (ADHD), and is biochemically modified by these drugs in animals. However, the effects of stimulants on the human VStr remain to be determined. We acquired anatomical brain MRI scans from 23 never-medicated adult patients with ADHD, 31 adult patients with a history of stimulant treatment and 32 control subjects, and VStr volumes were determined using individual rater-blinded region of interest delineation on high-resolution neuroanatomical scans. Furthermore, we also extracted VStr volumes before and after methylphenidate treatment in a subsample of the medication-naïve adult patients as well as in 20 never-medicated children with ADHD. We observed smaller VStr volumes in adult patients with a history of stimulant treatment in comparison to never-medicated patients. Moreover, our longitudinal analyses uncovered a reduction of grey matter volume in the bilateral VStr in adult patients after exposure to methylphenidate, which was followed by volumetric recovery to control level. In children, the same pattern of VStr volume changes was observed after treatment with methylphenidate. These findings suggest that the altered VStr volumes previously observed in patients with ADHD may represent a transitory effect of stimulant exposure rather than an intrinsic feature of the disorder. More generally, these data show that stimulant drugs can render plastic volume changes in human VStr neuroanatomy.