Oral presentation assessment and image reading behaviour on brain computed tomography reading in novice clinical learners: an eye-tracking study.

BACKGROUND: To study whether oral presentation (OP) assessment could reflect the novice learners' interpretation skills and reading behaviour on brain computed tomography (CT) reading. METHODS: Eighty fifth-year medical students were recruited, received a 2-hour interactive workshop on how to read brain CT, and were assigned to read two brain CT images before and after instruction. We evaluated their image reading behaviour in terms of overall OP post-test rating, the lesion identification, and competency in systematic image reading after instruction. Students' reading behaviour in searching for the target lesions were recorded by the eye-tracking technique and were used to validate the accuracy of lesion reports. Statistical analyses, including lag sequential analysis (LSA), linear mixed models, and transition entropy (TE) were conducted to reveal temporal relations and spatial complexity of systematic image reading from the eye movement perspective. RESULTS: The overall OP ratings [pre-test vs. post-test: 0 vs. 1 in case 1, 0 vs. 1 in case 2, p < 0.001] improved after instruction. Both the scores of systematic OP ratings [0 vs.1 in both cases, p < 0.001] and eye-tracking studies (Case 1: 3.42 ± 0.62 and 3.67 ± 0.37 in TE, p = 0.001; Case 2: 3.42 ± 0.76 and 3.75 ± 0.37 in TE, p = 0.002) showed that the image reading behaviour changed before and after instruction. The results of linear mixed models suggested a significant interaction between instruction and area of interests for case 1 (p < 0.001) and case 2 (p = 0.004). Visual attention to the target lesions in the case 1 assessed by dwell time were 506.50 ± 509.06 and 374.38 ± 464.68 milliseconds before and after instruction (p = 0.02). However, the dwell times in the case 2, the fixation counts and the frequencies of accurate lesion diagnoses in both cases did not change after instruction. CONCLUSION: Our results showed OP performance may change concurrently with the medical students' reading behaviour on brain CT after a structured instruction.

Hypothyroidism and risks of cerebrovascular complications among patients with head and neck cancer after radiotherapy.

BACKGROUND: Hypothyroidism (HT) and carotid artery stenosis (CAS) are complications of radiotherapy (RT) in patients with head and neck cancer (HNC). The impact of post-RT HT on CAS progression remains unclear. METHODS: Between 2013 and 2014, HNC patients who had ever received RT and were under regular follow-up in our hospital were initially screened. Patients were categorized into euthyroid (EU) and HT groups. Details of RT and HNC were recorded. Total plaque scores and degrees of CAS were measured during annual extracranial duplex follow-up. Patients were monitored for CAS progression to > 50 % stenosis or ischemic stroke (IS). Cumulative time to CAS progression and IS between the 2 groups were compared. Data were further analyzed based on the use or nonuse of thyroxine of the HT group. RESULTS: 333 HNC patients with RT history were screened. Finally, 216 patients were recruited (94 and 122 patients in the EU and HT groups). Patients of the HT group received higher mean RT doses (HT vs. EU; 7021.55 ± 401.67 vs. 6869.69 ± 425.32 centi-grays, p = 0.02). Multivariate Cox models showed comparable CAS progression (p = 0.24) and IS occurrence (p = 0.51) between the 2 groups. Moreover, no significant difference was observed in time to CAS progression (p = 0.49) or IS (p = 0.31) among patients with EU and HT using and not using thyroxine supplement. CONCLUSIONS: Our results did not demonstrate significant effects of HT and thyroxine supplementation on CAS progression and IS incidence in patients with HNC after RT.

Investigation of reactive astrogliosis effect on post-stroke cognitive impairment.

BACKGROUND: The aim of this study is to investigate the associations between post-stroke cognitive impairment (PSCI) severity and reactive astrogliosis (RA) extent on normalized 18F-THK-5351 positron-emission tomography (PET) imaging in amyloid-negative patients with first-ever stroke. METHODS: We prospectively enrolled 63 amyloid-negative patients with first-ever stroke. Neurocognitive evaluation, MRI, 18F-THK-5351, and 18F-florbetapir PET were performed around 3 months after stroke. The 18F-THK-5351 uptake intensity was normalized using a signal distribution template to obtain the Z-SUM scores as the RA extent in the whole brain and cerebral hemisphere ipsilateral to stroke lesion. We evaluated stroke volume, leukoaraiosis, and brain atrophy on MRI. We used a comprehensive neurocognitive battery to obtain composite cognitive scores, and defined PSCI as a general cognitive function score < - 1. We analyzed the influence of Z-SUM scores on PSCI severity after adjusting for demographic, vascular, and neurodegenerative variables. RESULTS: Twenty-five of 63 stroke patients had PSCI. Patients with PSCI had older age, lower education, and more severe cortical atrophy and total Z-SUM scores. Total Z-SUM scores were significantly associated with general cognitive and executive functions at multiple regression models. Path analyses showed that stroke can exert cognitive influence directly by stroke itself as well as indirectly through RA, including total and ipsilateral Z-SUM scores, in patients with either right or left hemisphere stroke. CONCLUSION: The patterns and intensity of 18F-THK-5351 uptake in amyloid-negative patients with first-ever stroke were associated with PSCI manifestations, which suggests that RA presents a modulating effect in PSCI development.

Computed Tomography Angiography in Acute Stroke Patients Receiving Recombinant Tissue Plasminogen Activator: Outcome and Safety Evaluations in an Asian Population.

INTRODUCTION: The multiphase computed tomography angiography (mCTA) is superior to the noncontrast computed tomography (NCCT) in selecting patients that would benefit from mechanical thrombectomy following an acute ischemic stroke (AIS). It remains unclear whether the longer examination time of mCTA worsens outcomes of intravenous recombinant tissue plasminogen activator (IV r-tPA) or increases the risk of hemorrhagic transformation (HT) compared to NCCT in Asian stroke patients. METHODS: Between January 2011 and December 2017, 199 AIS patients receiving IV r-tPA with initial National Institute of Health Stroke Scale (NIHSS) scores between 6 and 25 were enrolled in a single medical center. Onset-to-needle time (ONT), door-to-needle time (DNT), and creatinine levels before and after thrombolysis were recorded. We evaluated NIHSS scores 2, 24 h after treatment, and at discharge, the modified Rankin Scale (mRS) at discharge, and mortality rate. The presence of HT was reviewed within 7 days after thrombolysis. RESULTS: DNT, perithrombolysis creatinine levels, NIHSS, and mRS scores at the emergency room were similar between the NCCT and mCTA groups. ONT was shorter in the mCTA group. AIS patients got more significant neurologic improvement (NIHSS decrease ≥4) after thrombolysis and physically independent (mRS ≤2) at discharge in the mCTA group. Mortality rates, symptomatic, and total HT rates were similar between the NCCT and mCTA groups. CONCLUSION: Comparing to NCCT, mCTA-based IV r-tPA would not delay DNT nor worsen the outcome. Furthermore, mCTA provides more information for early identification of candidates for mechanical thrombectomy in Asian AIS patients.

Brain computerized tomography reading in suspected acute ischemic stroke patients: what are essentials for medical students?

BACKGROUND: Few systematic methods prioritize the image education in medical students (MS). We hope to develop a checklist of brain computerized tomography (CT) reading in patients with suspected acute ischemic stroke (AIS) for MS and primary care (PC) physicians. METHODS: Our pilot group generated the items indicating specific structures or signs for the checklist of brain CT reading in suspected AIS patients for MS and PC physicians. These items were used in a modified web-based Delphi process using the online software "SurveyMonkey". In total 15 panelists including neurologists, neurosurgeons, neuroradiologists, and emergency department physicians participated in the modified Delphi process. Each panelist was encouraged to express feedback, agreement or disagreement on the inclusion of each item using a 9-point Likert scale. Items with median scores of 7-9 were included in our final checklist. RESULTS: Fifty-two items were initially provided for the first round of the Delphi process. Of these, 35 achieved general agreement of being an essential item for the MS and PC physicians. The other 17 of the 52 items in this round and another two added items suggested by the panelists were further rated in the next round. Finally, 38 items were included in the essential checklist items of brain CT reading in suspected AIS patients for MS and PC physicians. CONCLUSIONS: We established a reference regarding the essential items of brain CT reading in suspected AIS patients. We hope this helps to minimize malpractice and a delayed diagnosis, and to improve competency-based medical education for MS and PC physicians.

Academic outcomes of flipped classroom learning: a meta-analysis.

CONTEXT: The flipped classroom (FC), reversing lecture and homework elements of a course, is popular in medical education. The FC uses technology-enhanced pre-class learning to transmit knowledge, incorporating in-class interaction to enhance higher cognitive learning. However, the FC model is expensive and research on its effectiveness remains inconclusive. The aim of this study was to compare the efficacy of the FC model over traditional lecture-based (LB) learning by meta-analysis. METHODS: We systematically searched MEDLINE, PubMed, ERIC, CINAHL, EMBASE, reference lists and Association for Medical Education in Europe (AMEE) conference books. Controlled trials comparing academic outcomes between the FC and LB approaches in higher education were considered eligible. The main findings were pooled using a random-effects model when appropriate. RESULTS: Forty-six studies (9026 participants) were included, comprising four randomised controlled trials (RCTs), 19 quasi-experimental studies and 23 cohort studies. Study populations were health science (n = 32) and non health science (n = 14) students. The risk of bias was high (36/37 articles). Meta-analyses revealed that the FC had significantly better outcomes than the LB method in examination scores (post-intervention and pre-post change) and course grades, but not in objective structured clinical examination scores. Subgroup analyses showed the advantage of the FC was not observed in RCTs, non-USA countries, nursing and other health science disciplines and earlier publication years (2013 and 2014). Cumulative analysis and meta-regression suggested a tendency for progressively better outcomes by year. Outcome assessments rarely focused on behaviour change. CONCLUSIONS: The FC method is associated with greater academic achievement than the LB approach for higher-level learning outcomes, which has become more obvious in recent years. However, results should be interpreted with caution because of the high methodological diversity, statistical heterogeneity and risk of bias in the studies used. Future studies should have high methodological rigour, a standardised FC format and utilise assessment tools evaluating higher cognitive learning and behaviour change to further examine differences between FC and LB learning.

Initial blood pressure is associated with stroke severity and is predictive of admission cost and one-year outcome in different stroke subtypes: a SRICHS registry study.

BACKGROUND: To investigate if initial blood pressure (BP) on admission is associated with stroke severity and predictive of admission costs and one-year-outcome in acute ischemic (IS) and hemorrhagic stroke (HS). METHODS: This is a single-center retrospective cohort study. Stroke patients admitted within 3 days after onset between January 1st and December 31st in 2009 were recruited. The initial BP on admission was subdivided into high (systolic BP ≥ 211 mmHg or diastolic BP ≥ 111 mmHg), medium (systolic BP 111-210 mmHg or diastolic BP 71-110 mmHg), and low (systolic BP ≤ 110 mmHg or diastolic BP ≤ 70 mmHg) groups and further subgrouped with 25 mmHg difference in systole and 10 mmHg difference in diastole for the correlation analysis with demographics, admission cost and one-year modified Rankin scale (mRS). RESULTS: In 1173 IS patients (mean age: 67.8 ± 12.8 years old, 61.4% male), low diastolic BP group had higher frequency of heart disease (p =0.001), dehydration (p =0.03) and lower hemoglobin level (p <0.001). The extremely high and low systolic BP subgroups had worse National Institutes of Health Stroke Scale (NIHSS) score (p =0.03), higher admission cost (p <0.001), and worse one-year mRS (p =0.03), while extremely high and low diastolic BP subgroups had higher admission cost (p <0.01). In 282 HS patients (mean age: 62.4 ± 15.4 years old, 60.6% male), both low systolic and diastolic BP groups had lower hemoglobin level (systole: p =0.05; diastole: p <0.001). The extremely high and low BP subgroups had worse NIHSS score (p =0.01 and p <0.001, respectively), worse one-year mRS (p =0.002 and p =0.001, respectively), and higher admission cost (diastole: p <0.002). CONCLUSIONS: Stroke patients with extremely high and low BP on admission have not only worse stroke severity but also higher admission cost and/or worse one-year outcome. In those patients with low BP, low admission hemoglobin might be a contributing factor.

Extracranial Carotid Artery Disease: Risk Factors and Outcomes in Patients With Acute Critical Hemispheric Ischemic Stroke.

OBJECTIVES: The prevalence of carotid disease in stroke patients has been underestimated because most stroke patients who receive carotid sonography have already survived the acute event. Little is known about the extracranial carotid arteries of patients with acute stroke who need intensive care. This study reviewed color-coded carotid duplex sonographic examinations of the extracranial carotid arteries of patients with acute critical hemispheric ischemic stroke. METHODS: We retrospectively reviewed 30 consecutive patients who had acute critical hemispheric ischemic stroke and received color-coded carotid duplex sonography in the intensive care unit. The presence of occlusive carotid artery disease was correlated with clinical features, vascular risk factors, and outcomes. RESULTS: Overall, 57% of the patients (17 of 30) had an occlusive internal carotid artery, and 44% of patients with atrial fibrillation (7 of 16) also had occlusive carotid disease. Eventually, 73% of the patients (21 of 30) had poor outcomes, and 57% (17 of 30) died. The contributing factors to a poor outcome were older age, an initial conscious disturbance, endotracheal intubation, and occlusive carotid disease, with the most significant factor being older age (P = .022; odds ratio, 27.76). The factors contributing to death were endotracheal intubation, occlusive carotid disease, and reversed ophthalmic flow, with the most significant factor being occlusive carotid disease (P = .014; odds ratio, 11.38). Soft homogeneously echogenic thrombi filling the lumen of the internal carotid artery and moving forward and backward with the carotid pulse were found in 3 patients. A small segment of ruptured plaque that was floating forward and backward with pulsation was found in 1 patient. CONCLUSIONS: Occlusive carotid artery disease is not uncommon among Chinese patients who have had an acute critical hemispheric infarction. Older age is the factor most significantly correlated with a poor outcome, and occlusive carotid disease is the factor most significantly correlated with death.

Joint model of multiple longitudinal measures and a binary outcome: An application to predict orthostatic hypertension for subacute stroke patients.

Stroke patients with orthostatic hypertensive responses that are one of the blood pressure regulation problems can easily fall down while doing rehabilitation, which may result in prolonged hospitalization and delayed treatment and recovery. This may result in increasing the medical cost and burden. In turn, developing a diagnostic test for the orthostatic hypertension (OH) is clinically important for patients who are suffering from stroke. Clinically, a patient needs to have a tilt testing that requires measuring the change of blood pressures and heart rate at all angles to determine whether a stroke patient has OH. It takes lots of time and effort to perform the test. Assuming there exist measurement errors when obtaining the blood pressures and heart rate at all angles, this paper proposes using multiple mixed-effect models to obtain the true trajectories of these measurements, which take into account the measurement error and the possible correlation among multiple measurements, and a logistic regression uses these true trajectories at a given time and other fixed-effect covariates as predictors to predict the status of OH. The joint likelihood function is derived to estimate parameters and the area under the receiver operating characteristics curve is used to estimate the predictive power of the model. Monte Carlo simulations are performed to evaluate the feasibility of the proposed methods. Also, the proposed model is implemented in the real data and provides an acceptable predictive power.

Presence of Gyriform Air Predicts Unfavorable Outcome in Venous Catheter-Related Cerebral Air Embolism.

BACKGROUND: This study aimed to investigate the clinical predictors of unfavorable prognosis in patients with venous catheter-related cerebral air embolism. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

BNG-1 in the Recovery of Acute Ischemic Stroke: A phase 2, Double-blind, Placebo-controlled Randomized Trial.

PURPOSE: Few strategies have been approved for acute therapy of ischemic stroke in Western medicine. Hundreds of traditional Chinese medicines (TCMs) have been used for stroke therapy and were rarely tested by qualified studies. To evaluate the efficacy and safety of BNG-1, a novel mixture of TCMs, in patients with acute ischemic stroke, we conducted the clinical trial. METHODS: This was a Phase 2, double-blind, placebo-controlled study in which the safety and efficacy of orally administered BNG-1 based on oral aspirin 100 mg daily for consecutive 14 days were measured in patients with acute ischemic stroke within 10 days after onset. The primary efficacy endpoint was the functional status assessed by the Barthel Index. The safety was evaluated by the incidence of adverse events and significant changes in vital signs, parameters of physical and laboratory examinations. RESULTS: There were 42 patients randomized for the intention-to-treat efficacy analysis. The study failed to prove the significantly statistical difference of efficacy assessment between patients receiving BNG- 1 and placebo in the recovery of acute ischemic stroke. The clinical and laboratory safety profiles had no significant difference between two groups. CONCLUSIONS: BNG-1 trial was feasible, safe and well tolerated for patients with acute ischemic stroke based on the treatment of aspirin, though there was no statistically significant difference of efficacy between BNG-1 and placebo groups. A further large Phase 3 trial of BNG-1 is needed before recommending such treatments for general clinical use.

Computer-aided diagnosis of hyperacute stroke with thrombolysis decision support using a contralateral comparative method of CT image analysis.

New and improved techniques have been continuously introduced into CT and MR imaging modalities for the diagnosis and therapy planning of acute stroke. Nevertheless, non-contrast CT (NCCT) is almost always used by every institution as the front line diagnostic imaging modality due to its high affordability and availability. Consequently, the potential reward of extracting as much clinical information as possible from NCCT images can be very great. Intravenous tissue plasminogen activator (tPA) has become the gold standard for treating acute ischemic stroke because it is the only acute stroke intervention approved by the FDA. ASPECTS scoring based on NCCT images has been shown to be a reliable scoring method that helps physicians to make sound decisions regarding tPA administration. In order to further reduce inter-observer variation, we have developed the first end-to-end automatic ASPECTS scoring system using a novel method of contralateral comparison. Due to the self-adaptive nature of the method, our system is robust and has good generalizability. ROC analysis based on evaluation of 103 subjects who presented to the stroke center of Chang Gung Memorial Hospital with symptoms of acute stroke has shown that our system's dichromatic classification of patients into thrombolysis indicated or thrombolysis contraindicated groups has achieved a high accuracy rate with AUC equal to 90.2 %. The average processing time for a single case is 170 s. In conclusion, our system has the potential of enhancing quality of care and providing clinical support in the setting of a busy stroke or emergency center.

Coexisting diseases of moyamoya vasculopathy.

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.

Enhanced versus standard hydration in acute ischaemic stroke: REVIVE - a randomised clinical trial.

RATIONALE: Early neurological deterioration (END) within 72 hours of stroke onset is associated with poor prognosis. Optimising hydration might reduce the risk of END. AIMS: To determine in acute ischaemic stroke patients if enhanced hydration versus standard hydration reduced the incidence of major (primary) and minor (secondary) END, as whether it increased the incidence of early neurological improvement (secondary), at 72 hours after admissionSample Size Estimate: 244 participants per arm. METHODS AND DESIGN: A prospective, double-blinded, multicentre, parallel-group, randomised controlled trial conducted at 4 hospitals from April 2014 to July 2020, with data analysed in August 2020. The sample size estimated was 488 participants (244 per arm). Ischaemic stroke patients with measurable neurological deficits of onset within 12 hours of emergency department presentation and blood urea nitrogen/creatinine (BUN/Cr) ratio ≥15 at point of admission were enrolled and randomised to 0.9% sodium chloride infusions of varying rates - enhanced hydration (20 mL/kg body weight, one-third given via bolus and remainder over 8 hours) versus standard hydration (60 mL/hour for 8 hours), followed by maintenance infusion of 40-80 mL/hour for the subsequent 64 hours. The primary outcome measure was the incidence of major early neurological deterioration at 72 hours after admission, defined as an increase in National Institutes of Health Stroke Scale of ≥4 points from baseline. RESULTS: 487 participants were randomised (median age 67 years; 287 females). At 72 hours: 7 (2.9%) in the enhanced-hydration arm and 5(2.0%) in the standard-hydration developed major early neurological deterioration (p=0.54). The incidence of minor early neurological deterioration and early neurological improvement did not differ between treatment arms. CONCLUSIONS AND RELEVANCE: Enhanced hydration ratio did not reduce END or improve short term outcomes in acute ischaemic stroke. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02099383, https://clinicaltrials.gov/study/NCT02099383).

Intracerebral hemorrhage after thrombolytic therapy in acute ischemic stroke patients with renal dysfunction.

PURPOSE: One complication of thrombolysis is intracranial hemorrhage (ICH). We investigated whether treatment with tissue plasminogen activator (t-PA) for ischemic infarction results in a higher risk of ICH in patients with kidney dysfunction, who are predisposed to treatment complications due to their bleeding tendency. METHODS: A total of 297 patients given thrombolytic therapy for ischemic stroke were classified into 2 groups on the basis of their estimated renal glomerular filtration rate (eGFR). The outcome measures included the incidence of ICH and modified Rankin scale scores at 1 month and 1 year. RESULTS: ICH was more common in the renal dysfunction group (23 vs. 12.5%). Nevertheless, multivariate logistic regression showed that the odds of ICH were not high in the group with low eGFR. Also, eGFR values <60 ml/min/1.73 m(2) did not predict the odds for functional dependence or death at 1 month and 1 year. CONCLUSION: After adjusting for confounding factors, the odds ratio for ICH was not higher in intravenous t-PA-treated stroke patients with renal dysfunction. A trend to the occurrence of ICH among these patients, however, was noted. Renal dysfunction does not predict the odds for functional dependence or death at 1 month and 1 year.

The impact of intracranial carotid artery calcification on the development of thrombolysis-induced intracerebral hemorrhage.

BACKGROUND: We aimed to assess whether intracranial carotid artery calcification (ICAC) evident on head computed tomography is a risk factor for symptomatic intracerebral hemorrhage (sICH) following tissue plasminogen activator (tPA) treatment for acute stroke. METHODS: We classified 297 consecutive patients into 2 groups (no to mild ICAC and moderate to severe ICAC) according to ICAC severity. Outcome measures included detection of intracerebral hemorrhage and assessment using a modified Rankin scale (mRS) at 1 month and 1 year after stroke. RESULTS: ICH (any type) was significantly more common in patients with moderate to severe ICAC than in patients with no to mild ICAC (22.5% versus 12%; relative risk [RR], 1.67; 95% confidence interval [CI], 1.1-2.5; P<.05). The moderate to severe ICAC group tended to have a higher percentage of sICH, but this association was not statistically significant (RR, 1.57; 95% CI, .75-3.3, P>.05). Multivariate adjusted regression analysis revealed that moderate to severe ICAC was an independent risk factor for ICH following tPA treatment (odds ratio, 2.52; 95% CI, 1.07-5.94; P=.04). Dependent functional outcome (mRS score 3-6) at 1-month and 1-year follow-up was significantly associated with moderate to severe ICAC (RR, 1.56; 95% CI, 1.06-2.27; and RR, 1.56; 95% CI, 1.06-2.33; P<.05). However, ICAC was not an independent factor of functional dependency at 1-month and 1-year follow-up in the final multivariate regression model. CONCLUSION: A significantly higher percentage of patients with moderate to severe ICAC developed ICH following tPA administration for stroke. ICAC severity is an independent risk factor for ICH events. ICAC severity can help predict short-term and long-term functional dependency in tPA-treated patients, although this can be confounded by other cardiovascular risk factors and stroke severity.

Brain computed tomography perfusion may help to detect hemodynamic reconstitution and predict intracerebral hemorrhage after carotid stenting.

OBJECTIVE: We 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. METHODS: From 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. RESULTS: After 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). CONCLUSIONS: Cerebral 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.

Predictors of clinical deterioration during hospitalization following acute ischemic stroke.

BACKGROUND/AIMS: A number of risk factors for early worsening of neurological symptoms have been identified. We aimed to evaluate the influence of hemorheologic, biochemical, and metabolic factors on neurological deterioration during hospitalization following acute ischemic stroke and develop a model of neurological deterioration. METHODS: Worsening of stroke was defined as a deleterious increase in NIH Stroke Scale (NIHSS) score of ≥4 points during hospitalization. We performed multivariate logistic regression analysis and constructed a prediction model based on chart data of 2,398 patients admitted at five medical centers; 203 of the patients had worsening of stroke and 2,186 had not. RESULTS: The results of multivariate logistic regression analysis showed that hemoglobin (odds ratio: 0.529) and albumin (odds ratio: 0.024) were significantly associated with stroke deterioration, as were the modified Rankin Scale on emergency department admission (odds ratio: 4.956) and length of hospitalization (odds ratio: 1.201). After adjusting for age, gender and NIHSS on emergency department admission, only hemoglobin (odds ratio: 0.894, 95% confidence interval: 0.814-0.981, p = 0.018) was associated with worsening. CONCLUSION: Hemoglobin and albumin were found to be risk factors for persistent neurological deterioration during hospitalization following acute ischemic stroke, suggesting that blood viscosity may be related to neurological deterioration.

Cervicocranial fibromuscular dysplasia in Taiwanese ischemic stroke patients.

INTRODUCTION: Clinical research of cervicocranial fibromuscular dysplasia (FMD) is rare in Asian populations. Our study reviewed Taiwanese ischemic stroke patients with cervicocranial FMD and compared them with previous reports. METHODS: Between 2000 and 2011, we collected 19 consecutive cervicocranial FMD patients who received demographic registration, a blood test for excluding vasculitis, and comprehensive angiography. Cerebral ultrasound, vascular images and clinical outcomes (Barthel index, modified Rankin scale, recurrent stroke, or death) were monitored during follow-up. RESULTS: Of the 19 patients, 16 (84%) had carotid FMD, while 7 (37%) had vertebral FMD. Only 2 investigated patients (13%) had renal FMD and 1 (5%) had cerebral aneurysm. 14 (74%) presented acute arterial dissection. All patients received medical treatment and had neither recurrent stroke nor dissection during follow-up. In the literature review of 225 FMD patients, 3.6% had recurrent stroke during follow-up, and some reported surgical procedure or angioplasty could give a good clinical outcome in progressing ischemia irrelevant to the cause of stenosis. CONCLUSION: In Taiwanese cervicocranial FMD patients, arterial dissection was one of the most common clinical presentations. Most of our patients had isolated involvement of the cervicocranial artery and carried a favorable outcome under medical treatment.

Mediating roles of leukoaraiosis and infarcts in the effects of unilateral carotid artery stenosis on cognition.

Background and objectives: Leukoaraiosis and infarcts are common in patients with carotid artery stenosis (CAS), and CAS severity, leukoaraiosis and infarcts all have been implicated in cognitive impairments. CAS severity was not only hypothesized to directly impede specific cognitive domains, but also transmit its effects indirectly to cognitive function through ipsilateral infarcts as well as periventricular leukoaraiosis (PVL) and deep white matter leukoaraiosis (DWML). We aimed to delineate the contributions of leukoaraiosis, infarcts and CAS to different specific cognitive domains. Materials and methods: One hundred and sixty one participants with unilateral CAS (>50%) on the left (n = 85) or right (n = 76) side and 65 volunteers without significant CAS (<50%) were recruited. The PVL, DWML, and infarct severity were visually rated on MRI. A comprehensive cognitive battery was administered and standardized based on age norms. Correlation and mediation analyses were adopted to examine the direct and indirect influence of CAS, leukoaraiosis, and infarct on specific cognitive domains with adjustment for education, hypertension, diabetes mellitus, and hyperlipidemia. Results: Carotid artery stenosis severity was associated with ipsilateral leukoaraiosis and infarct. Left CAS had direct effects on most cognitive domains, except for visual memory and constructional ability, and transmitted its indirect effects on all cognitive domains through ipsilateral PVL, and on constructional ability and psychomotor through infarcts. Right CAS only had negative direct effects on visual memory, psychomotor, design fluency and color processing speed, and transmitted its indirect effects on visual memory, word and color processing speed through ipsilateral infarcts. The trends of direct and indirect cognitive effects remained similar after covariate adjustment. Conclusion: Left and right CAS would predominantly lead to verbal and non-verbal cognitive impairment respectively, and such effects could be mediated through CAS-related leukoaraiosis and infarct. Given that cognition is subject to heterogeneous pathologies, the exact relationships between markers of large and small vessel diseases and their composite prognostic effects on cognition requires further investigation.