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Background and Purpose: Stenting is an important treatment for preventing stroke. However, the effect of vertebrobasilar stenting (VBS) might be limited because of relatively high periprocedural risks. Silent brain infarcts (SBIs) are known as a predictor for future stroke. Because of anatomical differences, factors for SBIs might be different between carotid artery stenting (CAS) and VBS. We compared the characteristics of SBIs between VBS and CAS. Methods: We included patients who underwent elective VBS or CAS. Diffusion‐weighted imaging was performed pre‐ and post‐procedure to detect new SBIs. Clinical variables, occurrence of SBIs, and procedure‐related factors were compared between CAS and VBS. Moreover, we investigated predictors of SBIs in each group separately. Results: Ninety‐two (34.2%) out of 269 patients had SBIs. SBIs were more frequently observed in VBS (29 [56.6%] vs. 63 [28.9%], p<.001). The risk of SBIs outside the stent‐inserted vascular territory was higher in VBS compared to CAS (14 [48.3%] vs. 8 [12.7%], p<.001). Larger‐diameter stents (odds ratio: 1.28, 95% confidence interval: 1.06‐1.54, p =.012) and prolonged procedure time (1.01, [1.00‐1.03], p =.026) increased the risk of SBIs in CAS, whereas only age increased the risk of SBIs in VBS (1.08 [1.01‐1.16], p =.036). Conclusions: Compared to CAS, VBS was associated with longer procedure time, more residual stenosis, and more SBIs, especially outside the stent‐inserted vascular territory. The risk of SBIs after CAS was associated with stent size and procedural difficulty. Only age was associated with SBIs in VBS. The pathomechanism of SBIs after VBS and CAS may be different. [ABSTRACT FROM AUTHOR]

Background and Purpose: Treatment of acute ischemic stroke is heavily contingent upon time, as there is a strong relationship between time clock and tissue progression. Work has established imaging biomarker assessments as surrogates for time since stroke (TSS), namely, by comparing signal mismatch between diffusion‐weighted imaging (DWI) and fluid‐attenuated inversion recovery (FLAIR) imaging. Our goal was to develop an automatic technique for determining TSS from imaging that does not require subspecialist radiology expertise. Methods: Using 772 patients (66 ± 9 years, 319 women), we developed and externally evaluated a deep learning network for classifying TSS from MR images and compared algorithm predictions to neuroradiologist assessments of DWI‐FLAIR mismatch. Models were trained to classify TSS within 4.5 hours and performance metrics with confidence intervals were reported on both internal and external evaluation sets. Results: Three board‐certified neuroradiologists' DWI‐FLAIR mismatch assessments, based on majority vote, yielded a sensitivity of.62, a specificity of.86, and a Fleiss' kappa of.46 when used to classify TSS. The deep learning method performed similarly to radiologists and outperformed previously reported methods, with the best model achieving an average evaluation accuracy, sensitivity, and specificity of.726,.712, and.741, respectively, on an internal cohort and.724,.757, and.679, respectively, on an external cohort. Conclusion: Our model achieved higher generalization performance on external evaluation datasets than the current state‐of‐the‐art for TSS classification. These results demonstrate the potential of automatic assessment of onset time from imaging without the need for expertly trained radiologists. [ABSTRACT FROM AUTHOR]

Disability in patients with acute stroke varies over time, with the prediction of outcomes being critical for proper management. This study aimed to develop a model to predict the cumulative probability of each modified Rankin Scale (mRS) score over time with inclusion of significant covariates. Longitudinal data obtained from 193 patients, 1–24 months after onset of acute ischemic stroke, were included for a modeling analysis using nonlinear mixed‐effect modeling (NONMEM). After selecting a model that best described the time course of the probability of different mRS scores, potential covariates were tested. Visual predicted check plots, parameter estimates, and decreases in minimum objective function values were used for model evaluation. The inclusion of disease progression (DP) in the baseline proportional odds cumulative logit model significantly improved the model compared to the baseline model without DP. An inhibitory maximum effect (Emax) model was determined to be the best DP model for describing the probability of specific mRS scores over time. In the final model, DP was multiplied with the baseline cumulative logit probability with a baseline adjustment. In addition to differences in lesion volume (DLV), the final model included comorbid diabetes mellitus (DM) and baseline National Institutes of Health Stroke Scale (NIHSS) scores on Emax as statistically significant covariates. This study developed a model including DLV, NIHSS score, and comorbid DM for predicting the disability time course in patients with acute ischemic stroke. This model may help to predict disease outcomes and to develop more appropriate management plans for patients with acute stroke. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE: The identification of high‐risk patent foramen ovale (PFO) is important for selecting suitable patients for PFO closure to prevent recurrent stroke in those with cryptogenic stroke. We aimed to evaluate the predictability of transcranial Doppler (TCD) in diagnosing high‐risk PFO compared with that of transesophageal echocardiography (TEE), which is not feasible for some stroke patients. METHODS: We retrospectively reviewed the data of 461 cryptogenic stroke patients who underwent TEE and TCD for PFO evaluation. High‐risk PFO on TEE was defined as PFO with atrial septal aneurysm (phasic septal excursion ≥10 mm) or large PFO (≥2 mm). Spencer grading of right‐to‐left shunt was used to classify the amount of shunt on TCD. RESULTS: PFO on TEE was observed for 242 (52.5%) patients, and high‐risk PFO was detected for 123 (26.7%) patients. However, PFO on TCD was observed for 336 (72.9%) patients. Among patients with significant shunt (Spencer grade III or higher) who underwent TCD after Valsalva maneuver (VM), 60.0% of patients had high‐risk PFO. However, only 5.3% of patients had high‐risk PFO among those without significant shunt. Receiver operating characteristic curves showed that significant shunt after VM had higher predictability (AUC =.876, 95% CI:.843‐.905) for detecting the high‐risk PFO compared with the predictability based on significant shunt at rest (AUC =.718, 95% CI:.674‐.759). (P<.0001 for the differences between two AUCs). CONCLUSIONS: TCD is a good screening tool for evaluating high‐risk PFO. VM is important for the evaluation of PFO. Patients with minimal or no shunt on TCD after VM are unlikely to have high‐risk PFO. [ABSTRACT FROM AUTHOR]

Background and Purpose: Quantitative measurements, as well as qualitative characterizations, of the vessel walls of the small intracranial arteries became clinically available and reliable beyond the resolution limit of 1.5 T high-resolution magnetic resonance imaging (HR-MRI) with the development of 3 T HR-MRI. We present the quantitative dissection findings of spontaneous and unruptured acute intracranial artery dissection (SID) using 3 T HR-MRI and investigate the differences between each cerebral artery.Methods: Twenty-eight lesions (anterior cerebral artery = 6; middle cerebral artery = 4; vertebral artery = 18) from 26 patients (17 male and 9 female patients; mean age = 47 years; age range = 32-74 years) with presumptive diagnoses of SID were included. The diagnosis was determined based on the clinical features, findings on luminal angiography (such as digital subtraction angiography, computed tomography, or magnetic resonance angiography), and HR-MRI. HR-MRI was performed within one month from onset. The neuroimaging indices (maximal outer diameter and area, remodeling index and modified remodeling index, and wall thickness and wall area index) of aneurysmal dilatation and the signal intensities of the intramural hematomas were rated using HR-MRI. The results were compared between each cerebral artery.Results: The maximal outer diameter and area, remodeling index and modified remodeling index, and wall thickness index and length were significantly different between anterior and posterior circulation (P < .05). The mean relative signal intensities of the intramural hematoma showed consistent values, regardless of the cerebral arteries, without significant difference.Conclusions: Neuroimaging indices of aneurysmal dilatation may be adjunctive indicators in the evaluation of SID. [ABSTRACT FROM AUTHOR]

Background: The confirmation of prothrombin time international normalized ratio by a central laboratory often delays intravenous thrombolysis in patients with acute ischemic stroke. Objectives: We investigated the feasibility, reliability, and usefulness of point-of-care determination of prothrombin time international normalized ratio for stroke thrombolysis. Methods: Among 312 patients with ischemic stroke, 202 who arrived at the emergency room within 4.5 h of stroke onset were enrolled in the study. Patients with lost orders for point-of-care testing for the prothrombin time international normalized ratio or central laboratory testing for the prothrombin time international normalized ratio (n = 47) were excluded. We compared international normalized ratio values and the time interval from arrival to the report of test results (door-to-international normalized ratio time) between point-of-care testing for the prothrombin time international normalized ratio and central laboratory testing for the prothrombin time international normalized ratio. In patients who underwent thrombolysis, we compared the time interval from arrival to thrombolysis (door-to-needle time) between the current study population and historic cohort at our center. Results: In the 155 patients included in the study, the median door-to-international normalized ratio time was 9.0 min (interquartile range, 5.0–12.0 min) for point-of-care testing for the prothrombin time international normalized ratio and 46.0 min (interquartile range, 38.0–55.0 min) for central laboratory testing for the prothrombin time international normalized ratio (p < 0.001). The intraclass correlation coefficient between point-of-care testing for the prothrombin time international normalized ratio and central laboratory testing for the prothrombin time international normalized ratio was 0.975 (95% confidence interval: 0.966–0.982). Forty-nine of the 155 patients underwent intravenous thrombolysis. The door-to-needle time was significantly decreased after implementation of point-of-care testing for the prothrombin time international normalized ratio (median, 23.0 min; interquartile range, 16.0–29.8 vs median, 46.0 min; interquartile range, 33.5–50.5 min). Conclusion: Utilization of point-of-care testing for the prothrombin time international normalized ratio was feasible in the management of patients with acute ischemic stroke. Point-of-care testing for the prothrombin time international normalized ratio was quick and reliable and had a pivotal role in expediting thrombolysis. [ABSTRACT FROM AUTHOR]

Abstract: Although stroke is a leading cause of disability, the quantitative relationship between baseline clinical and imaging characteristics and long‐term disability outcomes has rarely been studied. Prospectively collected clinical data from 405 patients with acute ischemic stroke including brain magnetic resonance images (MRIs) and disability outcomes assessed using the modified Rankin Scale (mRS) 3 month after the onset of disease were analyzed using a proportional odds cumulative logit model implemented in NONMEM. The relationship between the difference in lesion volume (DLV) — lesion volume measured by brain MRI 5 days later — lesion volume at the onset of the disease, and the mRS measured at 3 months (mRS3) was modeled first, and the potential covariates were tested. The Emax model best described the relationship between DLV and the logit probability of each mRS3. DLV, baseline stroke severity, age, and diabetes mellitus were identified as significant predictors of the probabilities of mRS3. The quantitative model constructed in the current analysis will enable us to predict the long‐term disabilities of the patients with acute ischemic stroke using the patient‐specific MRI and other clinical information, which will be useful for individualizing therapies and for making the clinical development of a novel drug more efficient. [ABSTRACT FROM AUTHOR]

Background and Purpose: (18) F-fluoromisonidazole (FMISO) positron emission tomography (PET) is used to image metabolically compromised but viable hypoxic tissue. We hypothesized that FMISO PET might predict early infarct growth in acute ischemic stroke patients with perfusion-diffusion mismatch in magnetic resonance imaging (MRI).Methods: We prospectively enrolled acute ischemic stroke patients who visited the emergency room within 48 hours after stroke onset and had perfusion-diffusion mismatch (>20%), as shown MRI. Infarct growth was defined as >20% increase of initial infarct volume or >5 mL in follow-up diffusion-weighted image 5 ± 2 days after stroke. The association between FMISO uptake and infarct growth was explored.Results: Of 19 enrolled patients, 10 (52.6%) showed increased FMISO uptake, with 8 of the latter showing infarct growth. None of the 9 patients who did not show FMISO uptake had infarct growth. FMISO uptake was significantly associated with infarct growth (Fisher's exact test; P < .01). FMISO PET scan had a sensitivity of 100% and a specificity of 82% (AUC = .909) in predicting infarct growth.Conclusions: FMISO PET scan can predict early infarct growth in acute ischemic stroke patients with perfusion-diffusion mismatch in MRI. [ABSTRACT FROM AUTHOR]

ABSTRACT BACKGROUND AND PURPOSE 18F-fluoromisonidazole (FMISO) positron emission tomography (PET) is used to image metabolically compromised but viable hypoxic tissue. We hypothesized that FMISO PET might predict early infarct growth in acute ischemic stroke patients with perfusion-diffusion mismatch in magnetic resonance imaging (MRI). METHODS We prospectively enrolled acute ischemic stroke patients who visited the emergency room within 48 hours after stroke onset and had perfusion-diffusion mismatch (>20%), as shown MRI. Infarct growth was defined as >20% increase of initial infarct volume or >5 mL in follow-up diffusion-weighted image 5 ± 2 days after stroke. The association between FMISO uptake and infarct growth was explored. RESULTS Of 19 enrolled patients, 10 (52.6%) showed increased FMISO uptake, with 8 of the latter showing infarct growth. None of the 9 patients who did not show FMISO uptake had infarct growth. FMISO uptake was significantly associated with infarct growth (Fisher's exact test; P < .01). FMISO PET scan had a sensitivity of 100% and a specificity of 82% (AUC = .909) in predicting infarct growth. CONCLUSIONS FMISO PET scan can predict early infarct growth in acute ischemic stroke patients with perfusion-diffusion mismatch in MRI. [ABSTRACT FROM AUTHOR]

Objective New brain infarcts after coronary artery bypass graft (CABG) are markedly more frequent than clinically evident stroke and have been proposed as a surrogate marker of postprocedural stroke. We sought to investigate the lesion patterns, mechanisms, and predictors of new brain infarction after CABG surgery. Methods This was a prospective pre- and postoperative brain magnetic resonance imaging (MRI) study in consecutive patients who underwent isolated CABG. Preoperative MRI included diffusion-weighted imaging (DWI) and magnetic resonance angiography. DWI was repeated on postoperative day 3. Clinical variables, intraoperative findings, and laboratory findings were compared between patients with and without new brain infarcts on DWI. Results Of a total of 127 included patients, 35 (27.6%) showed new brain infarcts on DWI. Most lesions were clinically silent, located in the cortical territory (80%), small (<1.5cm) in diameter (89%), and not related to the underlying cerebral arterial abnormality (80%). Old age (odds ratio [OR] = 1.09, 95% confidence interval [CI] = 1.03-1.15), use of cardiopulmonary bypass (OR = 3.12, 95% CI = 1.13-8.57), a moderate to severe aortic plaque (OR = 21.17, 95% CI = 2.01-222.58), and high levels of high-sensitivity C-reactive protein (OR = 1.35, 95% CI = 1.08-1.70) were independent predictors of new brain infarction. Interpretation Post-CABG new brain infarcts are mostly silent and cortically located. Old age, aortic arch atherosclerosis, use of cardiopulmonary bypass, and systemic inflammatory response may contribute to the pathogenesis of post-CABG new brain infarcts. Ann Neurol 2014;76:347-355 [ABSTRACT FROM AUTHOR]

Summary: Purpose: This study was undertaken to determine what patients with epilepsy need to know about their condition, and to discern what differences exist between patients' perceptions of this need and the medical profession's perception of what patients should know. Methods: Seventy-five consecutive patients with epilepsy and 56 medical personnel (residents and nurses) who were working in either Neurology or Neurosurgery Units were studied using a structured questionnaire consisting of 3 subsets with a total of 27 questions. Results: Using a Likert scale, epilepsy patients gave high priority to their need for more information about “how epilepsy is diagnosed,”“the structure of the brain” (p < 0.05, p < 0.01, respectively), and “the diet that might prevent the attack” (p < 0.05) than did medical personnel. Our study also revealed that men were more concerned with questions regarding smoking and drinking than were women (p < 0.05, respectively), whereas married patients gave higher scores in the category of employment (p < 0.01) and contraception/pregnancy (p < 0.05) than did unmarried patients. The patients with one or more seizures per month rated higher scores on questions concerning the first aid at the time of attack and dosage of antiepileptic drugs (AEDs; p < 0.05, respectively) than did the patients with fewer than one seizure per month. The patients taking poly-AED treatment gave higher scores on six items related to AED therapy than did those receiving monotherapy. No significant differences were found with regard to the length of time patients had the condition, nor to educational level or current employment status. Conclusions: An educational program for epilepsy patients should be developed on the basis of understanding that there are differences in perspectives among patients with different sociocultural contexts as well as between patients and medical personnel. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation detected after stroke (AFDAS) refers to the identification of newly diagnosed atrial fibrillation (AF) following an ischemic stroke in patients without known AF (KAF). The objective of this study was to compare the functional outcomes of patients diagnosed with AFDAS and those with KAF who underwent mechanical thrombectomy., Methods and Results: We conducted a retrospective analysis of patients who underwent mechanical thrombectomy and with either new AF diagnosed during hospitalization or KAF. We compared the baseline characteristics, clinical, and procedure-related variables between those with AFDAS and KAF. The primary outcome was the achievement of functional independence, defined as a modified Rankin Scale score of 0 to 2, at 3 months after stroke. Of the 252 patients, 101 (40.1%) were classified into the AFDAS group. The KAF group exhibited a higher rate of stroke history compared with the AFDAS group (32.5% versus 13.9%; P =0.001). Tandem occlusion was more common in the KAF group (13.2% versus 5.9%), while M2 occlusion was more common in the AFDAS group (11.3% versus 20.8%). The proportion of patients who achieved functional independence was higher in the AFDAS group (37.7% versus 52.5%; P =0.029). Multivariable analysis showed that AFDAS was associated with a favorable functional outcome (odds ratio, 2.67 [95% CI, 1.39-5.14]; P =0.003)., Conclusions: AFDAS demonstrated a positive association with functional independence in patients with stroke who underwent mechanical thrombectomy and were finally diagnosed to have AF during hospitalization. The observed disparities in occlusion site, intractable thrombus, and history of previous stroke may have contributed to these findings.

Background Which type of recurrent stroke is associated with pulse pressure (PP) remains uncertain in ischemic stroke with cerebral microbleeds or intracerebral hemorrhage. Methods and Results The PICASSO (Prevention of Cardiovascular Events in Ischemic Stroke Patients With High Risk of Cerebral Hemorrhage) database involving 1454 subjects was analyzed. Subjects were stratified into quartiles according to the distribution of mean PP (mm Hg) during follow-up (mean, 1.9 years): <47 (first quartile), 48 to 53 (second quartile), 54 to 59 (third quartile), and ≥60 mm Hg (fourth quartile). The primary end point was hemorrhagic stroke, and the secondary end points were ischemic stroke, stroke of any type, and major adverse cardiovascular events. Adjusted time-dependent area under the receiver operating characteristic curve analysis was performed to assess the prediction accuracy of mean PP. The mean frequency of visit for blood pressure checkup was 9.4±5.5 times. The stroke incidence rate per 100 person-years was 3.14, 2.24, 5.52, and 6.22, respectively in increasing quartile of mean PP, and the rate of major adverse cardiovascular events was 3.82, 2.84, 6.37, and 7.14, respectively. In the presence of mean arterial pressure, hemorrhagic stroke risk was higher in the highest quartile (adjusted hazard ratio, 6.03; 95% CI, 1.04-34.99) versus the lowest quartile, which was evident at higher mean systolic blood pressure. Higher mean PP as a continuous variable was also a predictor of hemorrhagic stroke (1.09, 1.03-1.15). The time-dependent area under the receiver operating characteristic curve for hemorrhagic stroke was 0.79. Conclusions Long-term elevated PP with higher systolic blood pressure confers a greater risk of subsequent hemorrhagic stroke among stroke patients with cerebral microbleeds or intracerebral hemorrhage. Registration URL: https://www.clinicaltrials.gov; Unique identifier, NCT01013532.