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Background: Severe headaches, projectile vomiting, focal neurological deficits and early onset seizure are regarded as early warning symptoms of subarachnoid hemorrhage (SAH). Earlier diagnosis based on such warning symptoms theoretically would improve the clinical prognosis. However, it is still not clear whether the prognosis is correlated with early warning symptoms. Here, we reviewed warning symptoms and other predictive factors in the emergency room (ER) setting and examined their correlations with mortality. Methods: Ninety saccular aneurysmal SAH cases were reviewed in a single medical center between January 2011 and December 2013. We examined differences in mortality rate related to warning symptoms, SAH scales, onset-to-ER time, hydrocephalus, and aneurysm size, location, and complexity. Logistic regression analyses were performed to determine the correlations of warning symptoms and other predictive factors with mortality. Receiver operating characteristic (ROC) curve analysis was used to calculate the area the under curve (AUC) of SAH mortality prediction tools. Results: Warning headache, projectile vomiting, the Hunt and Hess scale, Fisher scale, World Federation of Neurological Surgeons (WFNS) grading scale, and modified WFNS (m-WFNS) scale, body mass index, aneurysm complexity and hydrocephalus were significantly different between the survivors and the decedents. The warning headache and WFNS grade were strongly correlated with mortality. The rate of prognostic prediction improved from 90.4% to 94.6% when warning headache was additionally evaluated. Conclusions: With growing healthcare costs and recognition of the value of palliative care, early identification via warning headache and a detailed clinical history review is necessary for cases of aSAH. Keywords: Warning headache, SAH, WFNS, Survival rate

Objective Increased intracranial pressure (ICP) is a well-known complication after aneurysmal subarachnoid hemorrhage (aSAH). This study focused on the different temporal changes in ICP, mean arterial pressure, and cerebral perfusion pressure at the early stage of aSAH, throughout aneurysm embolization, and their effects on improvement in angiographic perfusion patterns. Methods Twenty-seven patients with aSAH were evaluated who underwent coiling and cerebrospinal fluid (CSF) drainage. Diagnostic angiography was performed to confirm the presence and location of the vascular lesion. The transit time of the capillary filling phase was defined as a surrogate of cerebral perfusion. Capillary filling transit times were compared before and after CSF drainage. Univariate and multivariate analyses were performed to identify associations between different physical parameters and capillary filling transit times. Results By univariate analysis, average capillary transit time before CSF drainage had a significant correlation with initial ICP (P = 0.0004; R2 = 0.398) but not systemic pressure (mean arterial pressure or cerebral perfusion pressure). Improvement in capillary filling pattern (i.e., a decrease in angiographic capillary transit time after CSF drainage) was seen in patients with high initial ICP and correlated with ICP difference after ventricular drainage (P = 0.0001 and P Conclusions Decreasing ICP by CSF drainage strongly correlated with improved cerebral microcirculation after aSAH. Further development of ICP control protocols that can provide better ICP management of patients with aSAH is warranted.

Background A ruptured vertebral artery dissecting aneurysm (VADA) with a high clinical grade (Hunt and Hess grade 5) has a devastating prognosis. Because of the high rebleeding rate and location, rapid mortality can occur in patients owing to brainstem compression. Adjuvant decompression of the posterior fossa after securing the aneurysm may improve the outcomes of these patients. Methods Between January 2011 and December 2016, 22 patients who presented with Hunt and Hess grade 5 ruptured VADA underwent endovascular treatment. Patients were divided into 2 groups: group 1 (n = 12) received conventional endovascular treatment of VADA and external ventricular drainage, and group 2 (n = 10) received external ventricular drainage and suboccipital craniectomy for posterior fossa decompression after rapid endovascular trapping of VADA. Results In group 2, the survival rate and good clinical outcome rate (modified Rankin scale score ≤2) were 80% and 60%, respectively, which were favorable to the corresponding rates in group 1 (66.67% and 16.67%). Moreover, 80% of patients (8/10) in group 2 regained consciousness compared with 50% of patients in group 1. Conclusions Adjuvant decompression of the posterior fossa can improve outcomes in patients with Hunt and Hess grade V ruptured VADA.

We investigate daily robust hedging performance with trading costs for markets of Standard and Poor's (S&P) 500 Index options (SPX) and Taiwan index options (TXO). In addition, we conduct a theoretical analysis to cope with the price limit constraint in TXO. Robust hedging refers to minimal model dependence on a risky asset price. Two hedging categories, including “Model-Free” and “Volatility-Model-Free,” are investigated, and nonparametric methods for volatility estimation are considered in our empirical study. In particular, instantaneous volatility is estimated by a proposed nonlinear correction scheme of the Fourier transform method (Malliavin & Mancino, 2009), justified by a simulation study for a local volatility model. We found an asymmetric phenomenon in hedging performance. Hedging portfolios constructed from the “Volatility-Model-Free” category were found to induce much higher Sharpe ratios than those from the “Model-Free” category on SPX, while they were found to perform comparably on TXO. Motivated from the price limit regulation in Taiwan, we further develop a time-scale change method to explain this phenomenon. Asymptotic moment estimates of differences in some hedging portfolios are consistent with our empirical findings.

This study aimed to investigate the clinical predictors of unfavorable prognosis in patients with venous catheter-related cerebral air embolism.An extensive review of English literature was performed to obtain reports on cerebral air embolism published between January 1982 and July 2014 through PubMed, Journal at Ovid, and Web of Science using the Mesh terms and keywords "cerebral air embolism" and "cerebral gas embolism." Reports not fulfilling the diagnosis of cerebral air embolism and iterant articles were excluded. Demographics, clinical manifestations, and imaging findings were recorded. The air distribution on initial brain computed tomography (CT) was recorded as gyriform air (GF), cavernous sinus bubble, venous sinus bubble, and parenchymal and subarachnoid bubble. The enrolled subjects were further divided into favorable and unfavorable outcome groups for analyses.Of the 33 cases enrolled, 31 had documented follow-up outcomes, including 14 with favorable and 17 with unfavorable prognoses. Patients with unfavorable outcome had older onset age (67.5 ± 15.8 versus 46.7 ± 17.0 years, P.001), higher frequency of GF on brain CT (58.8% versus 0%, P.01), initial consciousness disturbance (100% versus 42.9%, P.001), and hemiparesis (100% versus 42.9%, P.001), but lower frequency of cardiopulmonary symptoms (5.9% versus 64.3%, P.01). In patients with central venous catheter-related cerebral air embolism, the retrograde mechanism had a tendency for worse outcomes (43.8% versus 0%, P = .023).In patients with venous catheter-related cerebral air embolism, the presence of GF on brain CT imaging, old age, initial conscious disturbance, and hemiparesis may predict unfavorable outcomes.

Background Several coexisting diseases have been reported in patients with moyamoya vasculopathy (MMV), but studies of quasi-moyamoya disease (quasi-MMD) are rare. This study aims to investigate the frequency of known coexisting diseases in patients with quasi-MMD and to compare quasi-MMD with moyamoya disease (MMD). Methods Between 2000 and 2011, we retrospectively screened patients with International Classification of Diseases, Ninth Revision , code of 4375 (MMD) in the Health Information System of our hospital. The vascular images of each patient were confirmed by 2 neurologists and 1 neuroradiologist based on the diagnostic criteria of Japan Ministry of Health and Welfare. We excluded the patients with missing images and erroneous diagnosis. Demographics, coexisting diseases, laboratory data, treatment, and recurrent strokes were recorded. The eligible patients were divided into quasi-MMD and MMD groups according to the presence or absence of coexisting diseases. Results MMV was found in 90 patients including 37 (41.1%) quasi-MMD and 53 (58.9%) MMD. Atherosclerosis (32.4%) and thyroid disease (29.7%) were the leading coexisting diseases in quasi-MMD. Patients with MMD became symptomatic in a bimodal age distribution, whereas patients with quasi-MMD became symptomatic in a single-peak distribution. The prognosis of recurrent strokes was similar between quasi-MMD and MMD based on Kaplan–Meier analysis. Conclusions A bimodal distribution of onset age was noted in MMD, whereas a single-peak distribution was found in quasi-MMD. Coexisting diseases were usually underevaluated but were more common than expected in patients with MMV. Atherosclerosis and thyroid diseases were the leading coexisting diseases in different preferential age.

ObjectiveWe wanted to examine whether brain computed tomography (CT) perfusion can help to detect the reconstitution of cerebral hemodynamics and predict intracerebral hemorrhage (ICH) after carotid stenting.MethodsFrom September 2002 to October 2009, data of 114 patients with carotid intervention were prospectively collected, and we retrospectively identified a total of 108 consecutive patients with unilateral carotid stenting. Brain CT perfusion was studied at three time points: 1 week before, and 1 week and 6 months after stenting. Cerebral blood volume (CBV), cerebral blood flow, and time to peak (TTP) of brain CT perfusion were examined at cortical and subcortical areas of middle cerebral artery (MCA) and posterior cerebral artery territory. The CBV, cerebral blood flow, and TTP ratios of stenting side/nonstenting side were used for comparison. The flow direction of ophthalmic artery was detected by sonography, and the presence of anterior communicating artery was examined on prestenting cerebral angiogram.ResultsAfter carotid stenting, CBV and TTP ratios improved significantly in both MCA cortical and subcortical areas in patients with unilateral carotid stenosis (P < .01) but not in patients with bilateral carotid stenosis. Patients with reversed ophthalmic flow had better improvement of TTP in both MCA and posterior cerebral artery territories (P < .05) than patients with forward flow. However, no significant difference was found between patients with and patients without anterior communicating artery collateral (P > .05). The prestenting TTP ratio in MCA subcortical area was significantly higher in patients with poststenting ICH than patients without ICH (P = .0191).ConclusionsCerebral hemodynamics can be reconstituted within a few days after carotid revascularization, especially in patients with reversed ophthalmic flow. Prolonged TTP in prestenting MCA subcortical area may suggest a high risk of poststenting ICH.

Background/Purpose The clinical analyses and prognoses of mitochondrial diseases with A3243G mutation are rarely documented in Taiwan. Our study investigated the clinical phenotypes and the outcomes of patients with mitochondrial disease and the A3243G mutation of mtDNA in a Taiwanese population, and compared these with previous reports. Methods We retrospectively studied 22 consecutive patients with mitochondrial disease and the A3243G mutation of mtDNA in Chang Gung Memorial Hospital between 1988 and 2009. All patients underwent a detailed demographic registration, neurological examinations, a muscle biopsy, and mitochondrial DNA analysis. Modified Rankin scale, the presence of recurrent strokes or seizures, critical medical complications, and death were monitored during the follow-up period. Results Of the 22 patients, seizures and stroke-like episodes were found in 12 (55%). Visceral involvement, including cardiomyopathy, nephropathy, and pulmonary hypertension, were noted in five patients (23%). Patients with seizures had a high frequency of status epilepticus (92%) and a younger age of onset (21.3 ± 7.2 years). Both the Kaplan–Meier survival analysis and the Cox-regression model showed a marked deterioration in patients with seizures after 7 years of follow-up. Conclusion Our study found that seizures and status epilepticus are the most important predictive values for a poor outcome in patients with the mtA3243G mutation of mtDNA. Age of onset and visceral organ involvement had no prominent influence on the prognosis. Some medical complications could be well controlled or even reversed after management.

Animal studies have shown that cerebral hypoperfusion may be associated with amyloid plaque accumulation. Amyloid plaque is known to be associated with dementia and [(18)F]AV-45 is a positron emission tomography (PET) ligand that binds to extracelluar plaques. We hypothesized that demented patients with cerebral hypoperfusion may have increased [(18)F]AV-45 uptake. Five demented patients with cerebral hypoperfusion due to unilateral carotid artery stenosis (CAS) were examined with [(18)F]AV-45 PET, and the results were compared with six elderly controls. The standard uptake value ratio (SUVR) of each region of interest (ROI) was created using whole cerebellum as the reference region. All subjects underwent magnetic resonance imaging (MRI) for obtaining structural information. Patients with dementia and unilateral CAS had a higher global [(18)F]AV-45 SUVR (1.34 ± 0.06) as compared with controls (1.10 ± 0.04, p=0.0043), especially over the frontal, temporal, precuneus, anterior cingulate and occipital regions. The statistical distribution maps revealed a significantly increased [(18)F]AV-45 SUVR in the medial frontal, caudate, thalamus, posterior cingulate, occipital and middle and superior temporal regions ipsilateral to the side of CAS (p

To establish a prospective, real-time, self-sustainable stroke registry system, we incorporated a registry with an electronic chart to create an electronic chart-based stroke registry system in November 2006. The International Classification of Diseases Ninth Revision code (430–437) was used to auto-enroll stroke patients admitted to neurology departments. Clinical information was written by doctors, nursing information was recorded by nurses, and basic patient information was entered by administrative departments. Numerical data and the date and time of any studies were auto-downloaded from the hospital computer. In total, 212 items were auto-downloaded, including basic patient information, laboratory blood test and examination results, and the date and time of imaging and special intervention. The stroke scales (121 items, National Institutes of Health Stroke Scale, Barthel index, and modified Rankin scale) were designed to be auto-adjusted to reduce incompatibility. The 95 items with pull-down options were used to specify the contents. This registry system can be time-, labor- and money-saving with secured data accuracy.

In this work, an efficient two-dimensional numerical model is built to predict the critical fluences (Fc) during the irradiation of excimer laser on a-Si films. One aim of this paper is the modeling of conduction heat transfer with phase change. The specific heat/enthalpy method is used to handle the absorption and release of latent heat. It gives reasonably accurate results, when compared with the analytical solution of the Stefan problem. From the analysis of temperature responses, the Fc (full-melt threshold) obtained from the simulation results of the proposed model agree fairly well with those from the experimental data reported in the literature. It is also found that the variation of the surface reflectivity provides a useful means to observe the phase change and melting duration.

In this work, the excimer-laser-induced crystallization of amorphous silicon (a-Si) films was investigated numerically and experimentally. The basic structure is a silicon film on a glass substrate. Besides, the effect of an SiO2 buffer layer located between them was also studied. In the microstructure analysis of the laser-irradiated area, the critical fluences (full-melt threshold, Fc) between the partial-melting and complete-melting regimes can be found from the grain size distribution varying with laser intensity. An efficient two-dimensional numerical model was developed to predict the critical fluences (Fc) and the transient distribution of temperature during the laser heating of a-Si films. The Fc's obtained from the simulation results of the proposed model agree fairly well with those from the experimental ones reported in the literature and acquired in this research.