Impact of subcallosal artery origin and A1 asymmetry on surgical outcomes of anterior communicating artery aneurysms.

BACKGROUND: Surgical clipping of anterior communicating artery (ACoA) aneurysms remains challenging due to their complex anatomy. Anatomical risk factors for ACoA aneurysm surgery require further elucidation. The aim of this study is to investigate whether proximity of the midline perforating artery, subcallosal artery (SubCA), and associated anomaly of the ACoA complex affect functional outcomes of ACoA aneurysm surgery. METHODS: A total of 92 patients with both unruptured and ruptured ACoA aneurysms, who underwent surgical clipping, were retrospectively analyzed from a multicenter, observational cohort database. Association of ACoA anatomy with SubCA origin at the aneurysmal neck under microsurgical observation was analyzed in the interhemispheric approach subgroup (n = 56). Then, we evaluated whether anatomical factors associated with SubCA neck origin affected surgical outcomes in the entire cohort (both interhemispheric and pterional approaches, n = 92). RESULTS: In the interhemispheric approach cohort, combination of A1 asymmetry and aneurysmal size ≥ 5.0 mm was stratified to have the highest probability of the SubCA neck origin by a decision tree analysis. Then, among the entire cohort using either interhemispheric or pterional approach, combination of A1 asymmetry and aneurysmal size ≥ 5.0 mm was significantly associated with poor functional outcomes by multivariable logistic regression analysis (OR 6.76; 95% CI 1.19-38.5; p = 0.03) as compared with A1 symmetry group in the acute subarachnoid hemorrhage settings. CONCLUSION: Combination of A1 asymmetry and larger aneurysmal size was significantly associated with SubCA aneurysmal neck origin and poor functional outcomes in ACoA aneurysm surgery. Interhemispheric approach may be proposed to provide a wider and unobstructed view of SubCA for ACoA aneurysms with this high-risk anatomical variant.

[Preliminary Experience of a Biplane Flat Panel and Tailor-made Operating Table-equipped Hybrid Operating Room].

A hybrid operating room(Hybrid OR), where operative equipment and flat panel angiography are both available, is becoming common for complex cerebrovascular surgery. However, the current Hybrid OR remains suboptimal as it is not cost-effective and contains uncomfortable operating beds, and a single-plane flat panel. Therefore, we introduced a novel Hybrid OR system, which has a biplane flat panel detector and three mutually exchangeable tailor-made operating beds. In this article, we report our preliminary experience of this novel Hybrid OR, focusing on improved cost-effectiveness by the availability of diagnostic angiography and standard endovascular surgery, optimal selection of three different types of operating beds, and procedural workflow in individual hybrid cerebrovascular surgery.

Impact of Upper Limb Function and Employment Status on Return to Work of Blue-Collar Workers after Stroke.

BACKGROUND AND PURPOSE: Return to work (RTW) after stroke is the ultimate goal of the working population to achieve economic independence and well-being. Previous studies have reported lower RTW rates of blue-collar workers versus white-collar workers. Thus, investigating predictive factors for RTW of blue-collar workers is meaningful to improve RTW after stroke. Here, we investigate the physical, cognitive, and social factors associated with the RTW of blue-collar workers after stroke. METHODS: Poststroke rehabilitation data for 71 patients aged 15-64 years who had been active blue-collar workers at stroke onset were analyzed from a single-center observational cohort database. Baseline characteristics, social background factors, and quantitative assessments of the upper limb, lower limb, and cognitive functions at discharge were analyzed to identify any association with RTW. Receiver operating characteristic curve analysis was performed to determine the optimal cutoff value of continuous valuables with significant associations. RESULTS: Functional upper limb represented by an increasing Simple Test for Evaluating hand Function (STEF) score was independently associated with RTW of blue-collar workers by multivariable logistic regression analysis (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.01-1.14; p = .017). Correlation with self-employment status was also significant compared to that with employee status (OR, 185; 95% CI, 1.05-32400; p = .048). The cutoff value of the 100-point scale STEF to discriminate between RTW and non-RTW was 82. CONCLUSIONS: Functional upper limb and self-employment status were independent predictors for the RTW of blue-collar workers after stroke.

[Failed Surgical Clipping of a Posterior Communicating Artery Aneurysm with Oculomotor Nerve Palsy due to Ventricular Tachycardia:Validity of Endovascular Coiling in the Hybrid Operating Room].

Unruptured posterior communicating artery aneurysms with oculomotor nerve palsy are at high risk of rupture, and early intervention is recommended to prevent aneurysm bleeding and to improve oculomotor function. Both surgical clipping and endovascular coiling are available, and either of them is applied according to the anatomical condition and patient's comorbidity. In this article, we describe a case of an unruptured posterior communicating artery aneurysm with oculomotor nerve palsy, which was initially treated with surgical clipping. Owing to ventricular tachycardia during surgery, the craniotomy was discontinued and switched to endovascular coiling. In this operation, use of a hybrid operating room for coiling enabled adequate heparinization and immediate recraniotomy to prevent ischemic and hemorrhagic complications, respectively.

Attenuation of zinc-enhanced inflammatory M1 phenotype of microglia by peridinin protects against short-term spatial-memory impairment following cerebral ischemia in mice.

Activated microglia exhibit two opposite activation states, the inflammatory M1 and the anti-inflammatory M2 activation states. In the mammalian brain, ischemia elicits a massive release of zinc from hippocampal neurons, and the extracellular zinc primes M1 microglia-by inducing reactive oxygen species (ROS) generation-to enhance their production of proinflammatory cytokines, which ultimately results in short-term spatial memory impairment. Here, we examined how peridinin, a carotenoid in dinoflagellates, affects the zinc-enhanced inflammatory M1 phenotype of microglia. Treatment of microglia with 30-300 ng/mL peridinin caused a dose-dependent attenuation of zinc-enhanced interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNFα) secretion when M1 activation was induced by lipopolysaccharide exposure. Moreover, peridinin inhibited the increase in ROS levels in zinc-treated microglia without directly interacting with zinc. Notably, when mice were administrated peridinin (20-200 ng/animal) intracerebroventricularly 5 min before cerebral ischemia-reperfusion, the peridinin treatment not only suppressed the increase in expression of IL-1ß, IL-6, TNFα, and the microglial M1 surface marker CD16/32, but also protected the mice against ischemia-induced short-term spatial-memory impairment. Our findings suggest that peridinin prevents extracellular zinc-enhanced proinflammatory cytokine secretion from M1 microglia by inhibiting the increase in microglial ROS levels, and that this anti-inflammatory effect of peridinin might result in protection against deficits in short-term spatial memory.

[Two cases of spontaneous cervical epidural hematoma mimicking cerebral infarction].

Spontaneous spinal epidural hematoma(SSEH)is a rare condition that typically presents with acute back pain and paraparesis or quadriparesis. However, hemiparesis is a rare initial symptom of SSEH. Here, we report two cases of SSEH presenting with hemiparesis, which were difficult to distinguish from cerebral stroke. In both cases, source images of MR angiography were useful for the diagnosis of SSEH. The first patient was an 84-year-old man who presented with monoparesis in the left lower extremity, without back pain. He was initially misdiagnosed with a cerebral stroke and treated inappropriately with antiplatelet agents. Five days after admission, the correct diagnosis of SSEH was made based on cervical magnetic resonance imaging. Source images of cervical MR angiography also revealed SSEH. He was managed conservatively because of his relatively mild symptoms and stable condition, and his symptoms improved by rehabilitation. The second patient was a 72-year-old woman who presented with right hemiparesis and back pain. Source images of cervical MR angiography revealed a right posterolateral epidural hematoma, and underwent emergency surgical decompression and hematoma removal. We emphasize that SSEH should be considered in the differential diagnosis for patients with acute hemiparesis, even though they do not complain of back pain, and that source images of neck MR angiography could be useful for quickly screening for SSEH.

Impact of areal socioeconomic status on prehospital delay of acute ischaemic stroke: retrospective cohort study from a prefecture-wide survey in Japan.

OBJECTIVES: To examine whether the Areal Deprivation Index (ADI), an indicator of the socioeconomic status of the community the patient resides in, is associated with delayed arrival at the hospital and poor outcomes in patients with acute ischaemic stroke from a prefecture-wide stroke database in Japan. DESIGN: Retrospective study. SETTING: Twenty-nine acute stroke hospitals in Kochi prefecture, Japan. PARTICIPANTS: Nine thousand and six hundred fifty-one patients with acute ischaemic stroke who were urgently hospitalised, identified using the Kochi Acute Stroke Survey of Onset registry. Capital and non-capital areas were analysed separately. PRIMARY AND SECONDARY OUTCOME MEASURES: Prehospital delay defined as hospital arrival ≥4-hour after stroke onset, poor hospital outcomes (in-hospital mortality and discharge to a nursing facility) and the opportunities of intravenous recombinant tissue plasminogen activator (rt-PA) and endovascular reperfusion therapy. RESULTS: In the overall cohort, prehospital delay was observed in 6373 (66%) patients. Among individuals residing in non-capital areas, those living in municipalities with higher ADI (more deprived) carried a significantly higher risk of prehospital delay (per one-point increase, OR (95% CI) 1.45 (1.26 to 1.66)) by multivariable logistic regression analysis. In-hospital mortality (1.45 (1.02 to 2.06)), discharge to a nursing facility (1.31 (1.03 to 1.66)), and delayed candidate arrival ≥2-hour of intravenous rt-PA (2.04 (1.30 to 3.26)) and endovascular reperfusion therapy (2.27 (1.06 to 5.00)), were more likely to be observed in the deprived areas with higher ADI. In the capital areas, postal-code-ADI was not associated with prehospital delay (0.97 (0.66 to 1.41)). CONCLUSIONS: Living in socioeconomically disadvantaged municipalities was associated with prehospital delays of acute ischaemic stroke in non-capital areas in Kochi prefecture, Japan. Poorer outcomes of those patients may be caused by delayed treatment of intravenous rt-PA and endovascular reperfusion therapy. Further studies are necessary to determine social risk factors in the capital areas. TRIAL REGISTRATION NUMBER: This article is linked to a clinical trial to UMIN000050189, No.: R000057166 and relates to its Result stage.

The role of diurnal fluctuations in excitatory amino acid carrier 1 levels in post-ischemic hippocampal Zn2+ accumulation.

Accumulating evidence indicates time-of-day variations in ischemic neuronal injury. Under ischemic conditions, Zn2+ is massively released from hippocampal glutamatergic neurons, and intracellular Zn2+ accumulation results in neuron death. Notably, excitatory amino acid carrier 1 (EAAC1), known as a cysteine transporter, is involved in Zn2+ homeostasis, and its expressions exhibit a diurnal fluctuation. This study aimed to investigate whether time of day of an ischemic insult affects Zn2+ accumulation and neuronal injury and determine whether altered Zn2+ accumulation is modulated by EAAC1 diurnal fluctuation in the hippocampus in a mouse model of ischemic stroke. Mice subjected to transient global ischemia for 40 min at Zeitgeber time 18 (ZT18) (23:00) exhibited reduced Zn2+ accumulation and neuronal death in the hilar region of the hippocampus compared to those at ZT4 (09:00). The EAAC1 protein expression in the hippocampus was increased at ZT18 relative to ZT4. Intracerebroventricular injection of a non-selective excitatory amino acid transporter inhibitor, DL-threo-ß-benzyloxyaspartate, or a selective EAAC1 inhibitor, L-aspartic acid ß-hydroxamate, increased ischemia-induced Zn2+ accumulation and neuronal death in the hilus at ZT18. These findings suggest that ischemia-induced Zn2+ accumulation displays circadian fluctuations through diurnal variations in EAAC1 expressions and affects susceptibility to ischemic neuronal injury in the hippocampal hilar region.

The Cervical Spine as a Predominant Site of Cerebrospinal Fluid Leak: Preliminary Results Using the Overflow Leak Test.

BACKGROUND: Cerebrospinal fluid (CSF) hypovolemia is usually treated via an epidural blood patch (EBP). Accurate placement of the EBP at the site of CSF leakage is required for successful treatment of CSF hypovolemia. The thoracolumbar spine is evidently a common site of leakage, but because rates of detection of the leakage site via conventional imaging have historically not been high, there may be other common leakage sites. In this study, CSF leakage sites were identified via a combination of conventional imaging, a new method called the overflow leak test, and patient interviews. METHODS: CSF leakage sites were identified using computed tomography myelography, radioisotope cisternography, and the overflow leak test in 14 patients with CSF hypovolemia. The patients were also asked about their history with regard to potential trauma. EBP was performed, and the accuracy of leakage site identification was assessed. RESULTS: Conventional imaging identified a leakage site in 7 of 14 patients, and in most cases it was in the lumbar spine. In the remaining 7 cases, the overflow leak test and ascertaining a history of trauma facilitated identification of the cervical spine as a leakage site. The site of the EBP was the cervical spine in 10 patients and the lumbar spine in 4 patients. Complete recovery was observed in 13 of 14 patients. CONCLUSIONS: The cervical spine was a common leakage site in this study. Leakage in the cervical spine was undetectable via conventional imaging, suggesting that many cases of cervical spine leakage may remain undetected.

Three-dimensional Visualization of Aortic Arch Morphology via Rearrangement of Non-enhanced Thoracic CT Images.

Objective: The objective of this study was to evaluate the reproducibility of three-dimensional (3D) images of the aortic arch reconstructed using a novel image processing algorithm for non-enhanced computed tomography (CT) images of the cervicothorax and abdomen obtained before emergency endovascular surgery. Case Presentations: In all, 46 patients who underwent acute mechanical thrombectomy between January and December 2018 were examined. The anatomical variations of the aortic arch were reproduced in all cases; however, the reproduction of the carotid arteries was difficult. Conclusion: Our novel 3D analysis system enables obtaining information on the aortic arch easily from plain CT data that may be useful in acute endovascular treatment.

Acute Proximal Anterior Circulation Occlusion after Pulmonary Lobectomy Treated by Endovascular Therapy: Two Case Reports.

Objective: We report two cases of acute proximal anterior circulation occlusion after pulmonary lobectomy. Case Presentation: Case 1 was a 64-year-old male who presented with occlusion of the right middle cerebral artery (MCA) one day after left lower lobectomy. Case 2 was a 68-year-old male who presented with occlusion of the right internal carotid artery (ICA). In both cases, mechanical thrombectomy was performed for complete recanalization and symptoms were improved. Conclusion: Prompt mechanical thrombectomy in the acute phase after pulmonary lobectomy improved the prognosis of patients with acute proximal anterior circulation occlusion. It is important to share information about ischemic complications with medical staff engaged in thoracic surgery.

Zinc-aggravated M1 microglia regulate astrocytic engulfment via P2×7 receptors.

BACKGROUND: Glial cells such as astrocytes and microglia play an important role in the central nervous system via communication between these glial cells. Activated microglia can exhibit either the inflammatory M1 phenotype or the anti-inflammatory M2 phenotype, which influences astrocytic neuroprotective functions, including engulfment of cell debris. Recently, extracellular zinc has been shown to promote the inflammatory M1 phenotype in microglia through intracellular zinc accumulation and reactive oxygen species (ROS) generation. PURPOSE: Here, we investigated whether the zinc-enhanced inflammatory M1 phenotype of microglia affects the astrocytic engulfing activity. METHODS: Engulfing activity was assessed in astrocytes treated with microglial-conditioned medium (MCM) from lipopolysaccharide (LPS)-activated or from ZnCl2-pretreated LPS-activated M1 microglia. The effect of zinc on microglia phenotype was also validated using the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) and the ROS scavenger Trolox. RESULTS: Although treatment of astrocytes with LPS showed no significant effect on the engulfing activity, MCM from LPS-induced M1 microglia increased the beads uptake by astrocytes. This increased uptake activity was suppressed when MCM from LPS-induced M1 microglia pretreated with ZnCl2 was applied to astrocytes, which was further abolished by the intracellular zinc chelator TPEN and the ROS scavenger Trolox. In addition, expression of P2×7 receptors (P2×7R) was increased in astrocytes treated with MCM derived from M1 microglia but not in the M1 microglia pretreated with ZnCl2. CONCLUSION: These findings suggest that zinc pre-treatment abolishes the ability of LPS-induced M1 microglia to increase the engulfing activity in astrocytes via alteration of astrocytic P2×7R.

Impact of temperature decline from the previous day as a trigger of spontaneous subarachnoid hemorrhage: case-crossover study of prefectural stroke database.

OBJECTIVE: Several environmental factors have been reported to correlate with incidence of spontaneous subarachnoid hemorrhage (SAH). However, because of different patient selection and study designs among these studies, meteorological factors that trigger the incidence of SAH in a short hazard period remain unknown. Among meteorological factors, daily temperature changes may disrupt and violate homeostasis and predispose to cerebrovascular circulatory disturbances and strokes. The authors aimed to investigate whether a decline in the temperature from the highest of the previous day to the lowest of the event day (temperature decline from the previous day [TDP]) triggers SAH in the prefecture-wide stroke database. METHODS: All 28 participating institutions with primary or comprehensive stroke centers located throughout Kochi Prefecture, Japan, were included in the study. Data collected between January 2012 and December 2016 were analyzed, and 715 consecutive SAH patients with a defined date of onset were enrolled. Meteorological data in this period were obtained from the Kochi Local Meteorological Observatory. A case-crossover study was performed to investigate association of TDP and other environmental factors with onset of SAH. RESULTS: The increasing TDP in 1°C on the day of the SAH event was associated with an increased incidence of SAH (OR 1.041, 95% CI 1.007-1.077) after adjustment for other environmental factors. According to the stratified analysis, a significant association between TDP and SAH was observed in women, patients < 65 years old, and patients with weekday onset. Among these factors, increasing TDP had a great impact on SAH onset in patients < 65 years old (p = 0.028, Mann-Whitney U-test). CONCLUSIONS: TDP, temperature decline from the highest of the previous day to the lowest of the day, was correlated with the incidence of spontaneous SAH, particularly in younger patients < 65 years old.

The inhibitory role of intracellular free zinc in the regulation of Arg-1 expression in interleukin-4-induced activation of M2 microglia.

Microglia, the resident immune cells of the central nervous system, can display a pro-inflammatory M1 phenotype or an anti-inflammatory M2 phenotype. Arginase (Arg)-1 expressed in interleukin-4 (IL-4)-induced M2 microglia reduces nitric oxide (NO) production by competing with inducible NO synthase for l-arginine, which contributes to the attenuation of brain inflammation. Although previous studies have indicated that brain zinc promotes M1 activation, the effect of zinc on M2 microglial activation remains to be determined. In the present study, murine primary microglia treated with 10 ng mL-1 IL-4 exhibited increased Arg-1 mRNA expression and levels of intracellular free zinc. Chelation of this increased intracellular free zinc by the cell permeable zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN) aggravated the IL-4-induced mRNA expression and enzymatic activity of Arg-1. However, the cell impermeable zinc chelator CaEDTA had no effect on Arg-1 expression or cytosolic levels of free zinc in IL-4-induced M2-polarized microglia. Furthermore, treatment with IL-4 resulted in upregulation of phagocytic activity in microglia, while administration of TPEN abolished IL-4-induced phagocytic activity. Moreover, this effect was reversed vial-arginine supplementation. These findings suggest that IL-4 induces an increase in intracellular free zinc in microglia, which may act as a negative regulator of IL-4-induced Arg-1 expression, and that such negative regulation is essential for microglial phagocytic activity.

Remote effects in the ipsilateral thalamus and/or contralateral cerebellar hemisphere using FDG PET in patients with brain tumors.

PURPOSE: To evaluate reduced metabolism in the ipsilateral thalamus (TH) and/or contralateral cerebellum (CE) according to tumor localization and cortical metabolism around the tumor in patients with brain tumors based on FDG uptake. METHODS: This study investigated 48 consecutive patients with solitary cerebral hemisphere parenchymal brain tumors who underwent PET/CT and MRI. Patients were divided into 4 groups (A: reduced uptake in ipsilateral TH and contralateral CE, B: reduced uptake in ipsilateral TH only, C: reduced uptake in contralateral CE only, and D: no reduced uptake in ipsilateral TH or contralateral CE). FDG uptake and MRI findings were compared among these groups. RESULTS: Of 48 patients, group A included 24 (50%), group B included 10 (21%), group C included 0, and group D included 14 (29%). No significant tendencies were observed between the groups regarding tumor localization. However, reduced cortical metabolism around the tumor was observed in 22 patients in group A, 7 patients in group B, and 1 patient in group D. All patients in group B showed reduced metabolism from around the tumor up to the ipsilateral TH. CONCLUSION: Reduced FDG uptake in ipsilateral TH and contralateral CE usually occur simultaneously in patients with solitary brain tumors.