Warfarin Therapy and Percutaneous Left Atrial Appendage Closure for a Patient with Atrial Fibrillation and Antithrombin-III Deficiency.

Some patients develop ischemic stroke despite taking direct oral anticoagulants because of the presence of other risk factors such as coagulopathies. A 65-year-old male patient with non-valvular atrial fibrillation (NVAF) taking rivaroxaban was diagnosed as having embolic stroke and antithrombin-III (AT-III) deficiency. Echocardiography revealed a thrombus in the left atrial appendage (LAA). He was prescribed warfarin, and after resolution of the thrombus, we successfully performed percutaneous LAA closure (LAAC), with no subsequent recurrence or device-related thrombosis. Warfarin and LAAC may be feasible for NVAF patients with AT-III deficiency.

Study Profile of the Tsuruoka Metabolomics Cohort Study (TMCS).

The Tsuruoka Metabolomics Cohort Study (TMCS) is an ongoing population-based cohort study being conducted in the rural area of Yamagata Prefecture, Japan. This study aimed to enhance the precision prevention of multi-factorial, complex diseases, including non-communicable and aging-associated diseases, by improving risk stratification and prediction measures. At baseline, 11,002 participants aged 35-74 years were recruited in Tsuruoka City, Yamagata Prefecture, Japan, between 2012 and 2015, with an ongoing follow-up survey. Participants underwent various measurements, examinations, tests, and questionnaires on their health, lifestyle, and social factors. This study used an integrative approach with deep molecular profiling to identify potential biomarkers linked to phenotypes that underpin disease pathophysiology and provide better mechanistic insights into social health determinants. The TMCS incorporates multi-omics data, including genetic and metabolomic analyses of 10,933 participants and comprehensive data collection ranging from physical, psychological, behavioral, and social to biological data. The metabolome is used as a phenotypic probe because it is sensitive to changes in physiological and external conditions. The TMCS focuses on collecting outcomes for cardiovascular disease, cancer incidence and mortality, disability, functional decline due to aging and disease sequelae, and the variation in health status within the body represented by omics analysis that lies between exposure and disease. It contains several sub-studies on aging, heated tobacco products, and women's health. This study is notable for its robust design, high participation rate (89%), and long-term repeated surveys. Moreover, it contributes to precision prevention in Japan and East Asia as a well-established multi-omics platform.

A Case of Symptomatic Intraluminal Internal Carotid Artery Thrombus in a Patient with Essential Thrombocythemia Surgically Treated by CEA.

We report a patient with a symptomatic intraluminal internal carotid artery thrombus clinically revealed by cerebral infarction. In the preoperative evaluation, it was revealed that essential thrombocythemia existed in the background. Therefore, medical treatment with antithrombotic agents in conjunction with hydroxycarbamide for essential thrombocythemia was initiated, but the thrombus was not dissolved by three weeks. At this time, the patient underwent carotid endarterectomy, which removed the thrombus completely with its adjacent plaque without any perioperative stroke. The possibility of essential thrombocythemia may also be kept in mind when an increased platelet count is observed in patients with internal carotid artery thrombus. It is a reasonable option to precede medical treatment, including anticoagulant therapy, by setting the time limit for surgical intervention in such a disease state.

Cerebral Venous Thrombosis Mimicking Limbic Encephalitis.

Cerebral venous thrombosis (CVT) is challenging to diagnose, as it presents with variable symptoms. We encountered a complicated case of CVT that mimicked limbic encephalitis due to sensory aphasia. Based on the characteristic magnetic resonance imaging findings, this 72-year-old Japanese man was later confirmed to have CVT, the cause of which was periodontitis due to Eikenella corrodens, a Gram-negative facultative anaerobic that is part of the mouth's normal flora. The symptoms improved without sequelae following anticoagulation treatment and antibiotics. Clinicians should consider CVT as a differential diagnosis when unexplainable neurological symptoms suggesting limbic encephalitis are observed.

A case of moyamoya disease diagnosed as cerebral infarction in the early postpregnancy period and surgically treated by bilateral revascularization after term delivery.

We treated a 37-year-old Japanese woman with moyamoya disease who developed cerebral infarction in the early period after pregnancy and had undergone infertility treatment. After being adequately informed, including regarding the risk of stroke in the perinatal period and the option to prioritize the treatment of moyamoya disease even if the pregnancy was interrupted, the patient decided to continue the pregnancy and underwent surgical treatment after a full-term delivery by caesarean section. No new stroke was observed throughout the perinatal period or postoperative course. Since serious stroke during the perinatal period has also been reported in moyamoya disease, it is important to plan "tailored" treatment by sufficiently informing patients considering individual backgrounds and for multiple medical departments, including obstetrics, neurology, and neurosurgery departments, to carry out close outpatient follow-up in the perinatal period and carefully careful medication usage and radiological examinations.

A Case of Neurofibromatosis Type 1 Diagnosed after Idiopathic Rupture of Superficial Temporal Artery Pseudoaneurysm Requiring Endovascular Treatment.

Patients with neurofibromatosis type 1 not only have characteristic skin findings but are also known to have vascular disorders due to vascular vulnerability. A 44-year-old man with previously undiagnosed neurofibromatosis type 1 was brought to the emergency room due to a sudden subcutaneous hematoma with no history of trauma. Angiography revealed extravasation from the parietal branch of the right superficial temporal artery, which was embolized with n-butyl-2-cyanoacrylate. However, the next day, the patient exhibited an increased subcutaneous hematoma, and new extravascular leakage was detected at the frontal branch of the superficial temporal artery, which was also embolized with n-butyl-2-cyanoacrylate. The patient had physical findings characteristic of neurofibromatosis type 1, such as café-au-lait spots, and was subsequently diagnosed with neurofibromatosis type 1. No obvious neurofibroma or any other subcutaneous lesion associated with neurofibromatosis type 1 was identified in the affected area. Massive idiopathic arterial bleeding in the scalp, although infrequent, can be fatal. Neurofibromatosis type 1 should be considered when a subcutaneous scalp hematoma is observed without a history of trauma, even if the facial skin structure appears normal. Neurofibromatosis type 1 is also known to have multiple sources of hemorrhage. Thus, it is important to repeatedly evaluate vascular structures via cerebral angiography, contrast-enhanced computed tomography, and magnetic resonance imaging, if necessary.

"Missing-piece" sign with dural arteriovenous fistula at craniocervical junction: A case report.

OBJECTIVES: Spinal dural arteriovenous fistula (sDAVF) is a rare and often underdiagnosed spinal disease. Early diagnosis is required because the deficits are reversible and delays in treatment cause permanent morbidity. Although the abnormal vascular flow void is a critical radiographic feature of sDAVF, they are not always present. A characteristic enhancement pattern of sDAVF has been recently reported as the "missing-piece" sign which can lead to the early and correct diagnosis. METHODS: We presented imaging findings, treatment decisions, and the outcome of a rare case of sDAVF, in which the "missing-piece" sign appeared atypical. RESULTS: A 60-year-old woman developed numbness and weakness in her extremities. Spinal MRI revealed longitudinal hyperintensity in the T2-weighted image, extending from the thoracic level to medulla oblongata. At first, myelopathy with inflammation or tumor was suspected because of the lack of flow voids and vascular abnormalities in CT-angiography and MR-DSA. However, we administered intravenous methylprednisolone and her symptom got worse with the appearance of the "missing-piece" sign. Then, we successfully diagnosed sDAVF by angiography. The "missing-piece" sign was considered to derive from inconsistency of the intrinsic venous system of spinal cord, with the abrupt segments without enhancement. The same etiology was considered in our case. CONCLUSIONS: Detecting the "missing-piece" sign can lead to the correct diagnosis of sDAVF, even if the sign appeared atypical.

Stepwise improvement in limb shaking achieved by staged angioplasty for severe carotid stenosis.

Cerebral hyperperfusion syndrome is a rare but severe complication of carotid artery stenting or carotid endarterectomy. Staged angioplasty is reportedly an effective strategy to avoid cerebral hyperperfusion syndrome. We encountered a case of internal carotid artery stenosis with a rare clinical presentation of limb shaking that was successfully improved by staged angioplasty. To our knowledge, there are no reported cases of limb shaking treated with staged angioplasty.A 76-year-old woman presented with continuous chorea in her left lower limb and shoulder. Medical examination revealed a tiny cerebral infarction in the right corona radiata and severe right internal carotid artery stenosis. Angiography showed near occlusion of the right internal carotid artery. Staged angioplasty was performed to avoid the risk of cerebral hyperperfusion syndrome. The first angioplasty resulted in an expanded diameter of 2.5 mm and was followed by definitive carotid artery stenting using a closed-cell stent 3.5 weeks later. Limb shaking improved in a stepwise manner along with an improvement in internal carotid artery stenosis and distal flow state with no signs of cerebral hyperperfusion syndrome. Patients with internal carotid artery stenosis or occlusion presenting with limb shaking have been suggested to have impaired cerebrovascular reactivity, which is also thought to be a risk factor for cerebral hyperperfusion syndrome. The stepwise improvement in limb shaking observed in this case supports the idea that the pathophysiology of limb shaking is related to cerebral haemodynamic impairment. Measures to prevent cerebral hyperperfusion syndrome, including staged angioplasty, should be actively considered in patients with limb shaking because the symptoms themselves suggest severe hypoperfusion.

Impact of Coronavirus Disease 2019 on Time Delay and Functional Outcome of Mechanical Thrombectomy in Tokyo, Japan.

OBJECTIVES: An association has been reported between delays in the onset-to-door (O2D) time for mechanical thrombectomy (MT) and outbreaks of coronavirus disease 2019 (COVID-19). However, the association between other MT time courses or functional outcomes and COVID-19 outbreaks remains unclear. We compared the time courses of stroke pathways or functional outcomes in 2020 (the COVID-19 era) with those in 2019 (the pre-COVID-19 era) in Tokyo, Japan. MATERIALS AND METHODS: This retrospective observational study used data from the Tokyo-tama-REgistry of Acute endovascular Thrombectomy (TREAT), a multicenter registry of MT for acute large vessel occlusion in the Tokyo Metropolitan Area. Patients who had undergone acute MT from January 2019 to December 2020 were included. Patients were classified by the year they had undergone MT (2019 or 2020). RESULTS: In total, 477 patients were analyzed. O2D time was significantly longer in 2020 (146.0 min) than in 2019 (105.0 min; p = 0.034). No significant difference in door-to-puncture time (D2P) time or modified Rankin Scale (mRS) score 0-2 at 90 days was seen between 2019 and 2020. In the subgroup analysis, O2D time was significantly longer in the first half of 2020 compared with 2019. Multivariable logistic regression analysis revealed that the year 2020 was a independent predictor of longer O2D time, but not for mRS score 0-2 at 90 days. CONCLUSIONS: Although O2D time was significantly longer in the COVID-19 compared with the pre-COVID-19 era, D2P may not be significantly delayed and functional outcomes may not be different, despite the COVID-19 pandemic.

Carotenoid Nostoxanthin Production by Sphingomonas sp. SG73 Isolated from Deep Sea Sediment.

Carotenoids are used commercially for dietary supplements, cosmetics, and pharmaceuticals because of their antioxidant activity. In this study, colored microorganisms were isolated from deep sea sediment that had been collected from Suruga Bay, Shizuoka, Japan. One strain was found to be a pure yellow carotenoid producer, and the strain was identified as Sphingomonas sp. (Proteobacteria) by 16S rRNA gene sequence analysis; members of this genus are commonly isolated from air, the human body, and marine environments. The carotenoid was identified as nostoxanthin ((2,3,2',3')-ß,ß-carotene-2,3,2',3'-tetrol) by mass spectrometry (MS), MS/MS, and ultraviolet-visible absorption spectroscopy (UV-Vis). Nostoxanthin is a poly-hydroxy yellow carotenoid isolated from some photosynthetic bacteria, including some species of Cyanobacteria. The strain Sphingomonas sp. SG73 produced highly pure nostoxanthin of approximately 97% (area%) of the total carotenoid production, and the strain was halophilic and tolerant to 1.5-fold higher salt concentration as compared with seawater. When grown in 1.8% artificial sea salt, nostoxanthin production increased by 2.5-fold as compared with production without artificial sea salt. These results indicate that Sphingomonas sp. SG73 is an efficient producer of nostoxanthin, and the strain is ideal for carotenoid production using marine water because of its compatibility with sea salt.

Comparisons of Characteristics and Outcomes after Mechanical Thrombectomy for Vertebrobasilar Occlusion with Cardioembolism or Atherosclerotic Brain Infarction: Data from the Tokyo-Tama-Registry of Acute Endovascular Thrombectomy (TREAT).

BACKGROUND: Some reports suggest the efficacy of mechanical thrombectomy (MT) for acute vertebrobasilar artery (VBA) occlusion. The major causes of VBA occlusion include cardioembolism (CE) and large-artery atherosclerosis (LAA). However, the clinical characteristics of each cause remain unclear, and they might be important for decision making related to the indications and strategy of MT. OBJECTIVE: This study aimed to compare functional outcomes and factors affecting outcomes between patients with CE and LAA with acute VBA occlusion. METHODS: This was a retrospective and prospective observational study using data from TREAT (Tokyo-Tama-Registry of Acute Endovascular Thrombectomy), a multicenter registry of MT for acute large-vessel occlusion in the Tokyo metropolitan area. Patients with VBA occlusion classified into CE and LAA groups were analyzed. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days. RESULTS: Seventy-nine patients (57 with CE and 22 with LAA) were eligible from January 2015 to March 2020. Despite significantly shorter puncture-to-recanalization and onset-or-last-well-known-to-recanalization times in the CE group, the primary outcome was not significantly different between the 2 groups (CE, 31.6% vs. LAA, 45.5%; P = 0.248). In the subgroup analysis, patients with CE had worse clinical outcomes in the onset-or-last-well-known-to-door time ≥180 minutes, onset-or-last-well-known-to-door time ≥300 minutes, and low posterior circulation Alberta Stroke Program Early CT Score (≤7) subgroups. CONCLUSIONS: Functional outcomes of VBA occlusion were not significantly different between CE and LAA. Based on the subgroup analysis, patients with CE might have poorer collateral status than do patients with LAA, and earlier recanalization might therefore be desired.

Long-term Durability of Coil Embolization for Unruptured Aneurysm after Introduction of the Neck-bridge Stent: Comparison between the Pre-stent Era and the Stent Era.

More complex aneurysms can be treated by coil embolization with neck-bridge stent assistance. However, concerns about postprocedural ischemic or hemorrhagic complications remain. In this study, we assessed the long-term durability after introduction of neck-bridge stent in the context of coil embolization for unruptured aneurysm by comparing re-treatment and neurological events between the pre-stent and stent eras. Unruptured aneurysms treated by coil embolization between April 2005 and May 2018 were analyzed retrospectively. We divided cases into two groups: the pre-stent era and the stent era. The cumulative rate of re-treatment and neurological events were assessed and compared. During the period, 177 aneurysms were treated in the pre-stent era and 354 aneurysms were treated in the stent era. The median follow-up was 55 months. In the stent era, the dome/neck (D/N) ratio was significantly lower (P <0.001) and the number of aneurysms located at the posterior circulation was higher (P <0.001). A stent was used in 31.92% of cases in the stent era. The cumulative rate of re-treatment was significantly higher in the pre-stent era than it was in the stent era in univariate and multivariate analyses (P = 0.008, P = 0.008, respectively). The cumulative rate of neurological events was not significantly different between the two groups. The re-treatment rate has been improved without increasing neurological complications after introduction of the neck-bridge stent.

Suspected Cerebral Hyperperfusion Syndrome after Stenting for Intracranial Vertebral Artery Stenosis Associated with Reduced Cerebral Blood Flow to the Posterior Cerebral Artery Territory.

Objective: Although several studies have reported on cerebral hyperperfusion syndrome (CHS)/hyperperfusion phenomenon (HPP) involving the anterior circulation after carotid artery stenting (CAS), little is known about CHS/HPP involving the posterior circulation after percutaneous transluminal angioplasty (PTA) and stenting of the vertebral artery (VA). Case Presentation: A 79-year-old man with known chronic occlusion of the left VA (V4 segment) was admitted to another hospital with right-sided hemiplegia, mild disturbance of consciousness, and dysphagia. A head MRI revealed multiple infarcts in posterior circulation areas, and severe stenosis of the right VA (V4 segment). Single photon emission computed tomography (SPECT) indicated reduced cerebral blood flow (CBF) in the posterior circulation, and DSA revealed 76% stenosis of the right V4 segment. On day 18, PTA/stenting was performed under general anesthesia for the severe stenosis of the right VA. However, head MRI and CT on postoperative day (POD)1 showed intracranial hemorrhage (ICH) occupying an area measuring 2 cm in diameter in the left posterior lobe and a small subdural hematoma (SDH). SPECT on POD1 indicated increased CBF in the posterior lobe, and we diagnosed CHS might have caused ICH. Although SPECT on POD4 showed residual hyperperfusion, SPECT on POD11 revealed reduced CBF in the posterior circulation area. Conclusion: Our patient developed ICH after undergoing PTA/stenting for known severe symptomatic stenosis of the right VA. CHS/HPP in the posterior cerebral artery territory might be one of the etiologies, and reduced CBF prior to the procedure could be a risk factor for CHS/HPP developing after PTA/stenting.

Mechanically Induced Vasospasm and Postoperative Cerebral Infarction after Coil Embolization of Unruptured Cerebral Aneurysms in Anterior Circulation.

We occasionally encounter situations which requires retraction of the guiding system or administration of vasodilatory agents for mechanically induced vasospasm (MVS). However, whether MVS is associated with postoperative cerebral infarction has not been reported.To explore factors associated with MVS and to verify how MVS influences procedure outcomes,we reviewed consecutive cases of unruptured aneurysms in the anterior circulation treated with coil embolization between January 2017 and February 2020. Collected data included patients' clinical characteristics, devices, vessel tortuosity, severity of MVS, diameter of the parent vessel, and procedure duration. Significant MVS was defined as a condition necessitating a pause in the procedure. We also counted postoperative diffusion-weighted imaging (DWI) hyperintense spots (DHS). Parameters associated with MVS and postoperative DHS were investigated by multivariate logistic regression.A total of 103 cases met the eligibility criteria, with significant MVS occurring in 21 cases (20.3%), and postoperative DHS (≥3) confirmed in 30 cases (29.1%). Significant MVS was associated only with larger caliber at the tip of the guiding system compared with the parent vessel (p = 0.001). Postoperative DHS was associated with significant MVS (p = 0.002, OR: 5.313; 95% CI: 1.851-15.254).Significant MVS is a predictor of postoperative cerebral ischemia and occurs in patients with smaller caliber of the parent vessel. In patients with high-risk features for MVS, we should avoid navigating the guiding system forcibly through the narrow parent vessel. In other words, it is crucial to place the large-caliber guiding sheath/catheter proximally and only guide distally the intermediate catheter with better trackability.

Retrograde three-dimensional rotational angiography: A novel method for the detection of plaque protrusion during carotid artery stenting under continuous distal balloon protection.

BACKGROUND: To prevent ischemic complications during carotid artery stenting, accurate detection of plaque protrusion and appropriate additional treatment are essential. Here, we introduce a novel method for the detection of plaque protrusion under distal balloon protection using three-dimensional rotation angiography-"retrograde 3DRA." We evaluated the safety and efficacy of this method. MATERIALS AND METHODS: We retrospectively analyzed 28 consecutive carotid artery stenting procedures under distal balloon protection at our hospital between July 2017 and August 2019. The first line of protection was dual balloon protection (proximal and distal balloon). After stent deployment, balloon dilatation, and subsequent blood aspiration, 3DRA was performed with the injection of diluted contrast medium from the aspiration catheter positioned just proximal to the distal protection balloon. The stent lumen was analyzed by obtaining the reconstruction maximum intensity projection image. RESULTS: Among the 28 cases, all cases could be assessed for in-stent plaque protrusion using "retrograde 3DRA." We were able to evaluate the stent lumen clearly. There were three cases (10.7%) in which plaque protrusion could be confirmed. Since additional balloon dilatation was performed for all protrusion cases under continuing balloon protection, no ischemic complications occurred. CONCLUSION: Retrograde 3DRA could be safe and useful for the detection of plaque protrusions and to avoid ischemic complication for tolerable cases of internal carotid artery transient balloon protection.

Comparing Retreatments and Expenditures in Flow Diversion Versus Coiling for Unruptured Intracranial Aneurysm Treatment: A Retrospective Cohort Study Using a Real-World National Database.

BACKGROUND: Flow diverters (FDs) have marked the beginning of innovations in the endovascular treatment of large unruptured intracranial aneurysms, but no multi-institutional studies have been conducted on these devices from both the clinical and economic perspectives. OBJECTIVE: To compare retreatment rates and healthcare expenditures between FDs and conventional coiling-based treatments in all eligible cases in Japan. METHODS: We identified patients who had undergone endovascular treatments during the study period (October 2015-March 2018) from a national-level claims database. The outcome measures were retreatment rates and 1-yr total healthcare expenditures, which were compared among patients who had undergone FD, coiling, and stent-assisted coiling (SAC) treatments. The coiling and SAC groups were further categorized according to the number of coils used. Retreatment rates were analyzed using Cox proportional hazards models, and total expenditures were analyzed using multilevel mixed-effects generalized linear models. RESULTS: The study sample comprised 512 FD patients, 1499 coiling patients, and 711 SAC patients. The coiling groups with ≥10 coils and ≥9 coils had significantly higher retreatment rates than the FD group with hazard ratios of 2.75 (1.30-5.82) and 2.52 (1.24-5.09), respectively. In addition, the coiling group with ≥10 coils and SAC group with ≥10 coils had significantly higher 1-year expenditures than the FD group with cost ratios (95% CI) of 1.30 (1.13-1.49) and 1.31 (1.15-1.50), respectively. CONCLUSION: In this national-level study, FDs demonstrated significantly lower retreatment rates and total expenditures than conventional coiling with ≥ 9 coils.

Clinical Characteristics and Endovascular Treatment for Spinal Dural Arteriovenous Fistula in Japan: Japanese Registry of Neuroendovascular Therapy 2 and 3.

A subgroup analysis of spinal vascular lesions registered in the Japanese Registry of Neuroendovascular Therapy 2 (JR-NET2) and JR-NET3 was performed. About 172 analyzable cases of spinal dural arteriovenous fistula (SDAVF) were assessed, including the characteristics, treatment strategy, and treatment outcome. SDAVF was more common in middle-aged and older males. The most commonly affected area was the thoracolumbosacral region (83.7%), and most cases had a non-hemorrhagic onset (89.0%). Complete obliteration was achieved in 54.7%. Treatment-related complications occurred in three patients (7.0%). Post-treatment neurological improvement was achieved in 48.3%. The primary endpoint [modified Rankin Scale (mRS) score of 0-2 on postoperative day 30] was achieved in 60.5% of the cases. As a new discovery, the incidence of cervical SDAVF increased from 1.8% in JR-NET2 to 19.7% in JR-NET3. Compared with non-cervical SDAVF, cervical SDAVF was characterized by a higher proportion of hemorrhagic onset (P <0.01), incomplete obliteration of the shunt (P <0.01), and embolization-related complications (P = 0.01). Overall, a mRS of 0-2 on postoperative day 30 was correlated with a pre-treatment mRS of 0-2 (P <0.01) in a univariate analysis. Complete obliteration of the shunt was the only predictor of postoperative neurological improvement (P = 0.001) in a multivariate analysis. Endovascular treatment for SDAVF has been safely administered in Japan. The incidence of cervical SDAVF, which has more aggressive features, appears to be increasing. Early diagnosis and complete obliteration of the shunt are important for improving the treatment outcomes of patients with SDAVF.

Rivaroxaban Promotes Reduction of Embolus Size within Cerebrocortical Microvessels in a Mouse Model of Embolic Stroke.

Previous reports have suggested that direct oral anticoagulants exert a prothrombolytic effect against intracardiac thrombi. We hypothesized that these anticoagulants may also help recanalize occluded intracranial arteries via prothrombolytic effects. In this study, we evaluated the effects of rivaroxaban, a direct oral anticoagulant, on fibrin emboli within the cerebrocortical microvessels in a mouse model of embolic stroke. Fibrin emboli prepared ex vivo were injected into the common carotid artery of male C57BL/6 mice, and embolization in the microvessels on the brain surface was observed through a cranial window. Oral administration of rivaroxaban was initiated a week before injection of the emboli. The number and sizes of the emboli were measured at two time points: immediately after and 3 h after the embolus injection in the rivaroxaban-treated mice (n =6) and untreated mice (n =7). The rates of recanalization and change in the embolus size were analyzed between the two groups. Complete recanalization was observed only in the rivaroxaban group (three mice in the rivaroxaban group compared with none in the control group). A significantly higher rate of reduction of the embolus size was observed in the rivaroxaban group than in the control group (P=0.0216). No significant differences between the two groups were observed in the serum levels of the following coagulation markers: thrombin-antithrombin III complexes, D-dimers, or plasmin-α2-plasmin inhibitor complex. Our findings indicate that rivaroxaban may promote reduction in the size of stagnated fibrin emboli in cerebrocortical microvessels in cases of embolic stroke.

Trends of Antiplatelet Therapy for the Management of Moyamoya Disease in Japan: Results of a Nationwide Survey.

BACKGROUND: The efficacy and safety of antiplatelet drugs in the treatment of moyamoya disease remain unclear. This study reports results of a nationwide survey conducted in 2016 on the trends of antiplatelet therapy for moyamoya disease in Japan. METHODS: Data were obtained through questionnaires related to treatment policies regarding antiplatelet drugs from each specialized stroke management department of 765 hospitals in Japan. Data were also compared between experienced facilities (defined as facilities managing more than 10 cases per year) and those less experienced (not more than 10 cases per year) to determine experts' opinion. RESULTS: Of the 389 departments in 375 hospitals that responded, 330 departments provided medical care for moyamoya disease. Regarding ischemic stroke, numerous departments considered the use of antiplatelet drugs "in principle" (218 departments). After surgery for ischemic moyamoya disease, the use of antiplatelet drugs for a certain period of time was the most popular opinion (74 departments). Regarding asymptomatic moyamoya disease, majority departments reported no use of APDs "in principle" (256 departments). The experienced facilities reported "no use of antiplatelet drugs" more frequently than those less experienced for treating asymptomatic moyamoya disease. In moyamoya disease, aspirin was the most commonly used antiplatelet drugs followed by cilostazol and clopidogrel. CONCLUSIONS: This survey revealed details of treatment policies, and the selection of antiplatelet drugs widely varied across facilities. Further prospective studies are necessary to improve the current unclear situation regarding the use of antiplatelet drugs for the management of moyamoya disease.

Diameter of fluorescent microspheres determines their distribution throughout the cortical watershed area in mice.

A hemodynamic mechanism has long been assumed to play an important role in watershed infarction. In recent years, however, clinical evidence has indicated that an embolic mechanism is involved. The mechanism by which emboli are trapped preferentially in watershed areas remains unclear. In the present study, we developed a mouse embolus model using fluorescent microspheres with different diameters and evaluated the role of the microspheres' diameters in the generation of a watershed-patterned distribution. We injected fluorescent microspheres of four different diameters (i.e., 13, 24, 40, and 69 µm) into the internal carotid artery of C57BL/6 mice either (1) without ligation of the common carotid artery (normal perfusion pressure model: NPPM) or (2) with ligation of the common carotid artery (low perfusion pressure model: LPPM). Left common carotid artery ligation induced reductions in local cerebral blood flow in both the periphery and the core area of the left middle cerebral artery. A greater reduction in the border-zone area between the left anterior cerebral artery and the middle cerebral artery was also noted. After 24 h, the brains were removed and the distribution of the microspheres in the brain was evaluated using a fluorescence microscope. The 24-µm microspheres were distributed in the watershed area more frequently than the other microsphere sizes (P < .05, ANOVA followed by Tukey's test). Meanwhile, the distribution rates were similar between the NPPM and LPPM models for all microsphere sizes. This study suggested that the distribution pattern of the microspheres was only affected by the microspheres' diameters.