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Background: The present study aimed to clarify the association between left atrial (LA) size and ischemic events after ischemic stroke or transient ischemic attack (TIA) in patients with nonvalvular atrial fibrillation (NVAF). Methods: Acute ischemic stroke or TIA patients with NVAF were enrolled. LA size was classified into normal LA size, mild LA enlargement (LAE), moderate LAE, and severe LAE. The ischemic event was defined as ischemic stroke, TIA, carotid endarterectomy, carotid artery stenting, acute coronary syndrome or percutaneous coronary intervention, systemic embolism, aortic aneurysm rupture or dissection, peripheral artery disease requiring hospitalization, or venous thromboembolism. Results: A total of 1,043 patients (mean age, 78 years; 450 women) including 1,002 ischemic stroke and 41 TIA were analyzed. Of these, 351 patients (34%) had normal LA size, 298 (29%) had mild LAE, 198 (19%) had moderate LAE, and the remaining 196 (19%) had severe LAE. The median follow-up duration was 2.0 years (interquartile range, 0.9–2.1). During follow-up, 117 patients (11%) developed at least one ischemic event. The incidence rate of total ischemic events increased with increasing LA size. Severe LAE was independently associated with increased risk of ischemic events compared with normal LA size (multivariable-adjusted hazard ratio, 1.75; 95% confidence interval, 1.02–3.00). Conclusion: Severe LAE was associated with increased risk of ischemic events after ischemic stroke or TIA in patients with NVAF.

OBJECTIVE We compared outcomes after treatment with direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) and a recent cerebral ischemia. METHODS We conducted an individual patient data analysis of seven prospective cohort studies. We included patients with AF and a recent cerebral ischemia (

Background Patients with vascular Ehlers-Danlos syndrome (EDS) occasionally suffer from arterial dissection. Eagle syndrome, which is caused by an elongated styloid process and also causes arterial dissection, is difficult to diagnose and could sometimes be overlooked. Little is known of the coexistence of these two diseases, and treatment strategy is not established. Here, we present a case of bilateral internal carotid artery (ICA) dissection due to Eagle syndrome in a patient with vascular EDS. Case presentation A 30-year-old man was admitted to our hospital because of sudden onset of mild sensory disturbance in his left limbs. He had a history of Ehlers-Danlos syndrome (EDS) and also had left cervical internal carotid artery (ICA) dissection 3 years before. Diffusion-weighted imaging showed acute cerebral infarcts in the right hemisphere. Cervical computed tomography angiography (CTA) revealed the right ICA narrowing at the cervical portion in addition to the previous left cervical ICA dissection. Cervical magnetic resonance imaging (MRI) revealed double-lumen and intramural hematoma at the narrowing portion of the right cervical ICA, which indicates arterial dissection. CT also revealed bilateral elongated styloid processes which are close to each side of cervical ICA. We diagnosed him as bilateral ICA dissection due to bilateral Eagle syndrome. Considering vascular complications due to vascular EDS, we performed closer follow-up with transoral carotid ultrasonography (TOCU). In 4 months, his right ICA dissection gradually improved without stroke recurrence or deterioration of dissection. Conclusions Since patients with vascular EDS easily develop arterial dissection, Eagle syndrome may be overlooked. Clinicians should consider Eagle syndrome in the case of vascular EDS with extracranial ICA dissection and close follow-up should be prioritized in cases of Eagle syndrome with vascular EDS.

Background and Purpose— We aimed to compare outcomes of ischemic stroke patients with nonvalvular atrial fibrillation between earlier and later initiation of direct oral anticoagulants (DOACs) after stroke onset. Methods— From data for 1192 nonvalvular atrial fibrillation patients with acute ischemic stroke or transient ischemic attack in a prospective, multicenter, observational study, patients who started DOACs during acute hospitalization were included and divided into 2 groups according to a median day of DOAC initiation after onset. Outcomes included stroke or systemic embolism, major bleeding, and death at 3 months, as well as those at 2 years. Results— DOACs were initiated during acute hospitalization in 499 patients in median 4 (interquartile range, 2–7) days after onset. Thus, 223 patients (median age, 74 [interquartile range, 68–81] years; 78 women) were assigned to the early group (≤3 days) and 276 patients (median age, 75 [interquartile range, 69–82] years; 101 women) to the late (≥4 days) group. The early group had lower baseline National Institutes of Health Stroke Scale score and smaller infarcts than the late group. The rate at which DOAC administration persisted at 2 years was 85.2% overall, excluding patients who died or were lost to follow-up. Multivariable Cox shared frailty models showed comparable hazards between the groups at 2 years for stroke or systemic embolism (hazard ratio, 0.86 [95% CI, 0.47–1.57]), major bleeding (hazard ratio, 1.39 [95% CI, 0.42–4.60]), and death (hazard ratio, 0.61 [95% CI, 0.28–1.33]). Outcome risks at 3 months also did not significantly differ between the groups. Conclusions— Risks for events including stroke or systemic embolism, major bleeding, and death were comparable whether DOACs were started within 3 days or from 4 days or more after the onset of nonvalvular atrial fibrillation–associated ischemic stroke or transient ischemic attack. Registration— URL: https://www.clinicaltrials.gov . Unique identifier: NCT01581502.

Background We aimed to clarify associations between prior anticoagulation and short‐ or long‐term clinical outcomes in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation. Methods and Results A total of 1189 ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation who were hospitalized within 7 days after onset were analyzed. Of these, 813 patients (68.4%) received no prior anticoagulation, 310 (26.1%) received prior warfarin treatment with an international normalized ratio ( INR ) INR ≥2 on admission, and the remaining 38 (3.2%) received prior direct oral anticoagulant treatment. Prior warfarin treatment was associated with a lower risk of death or disability at 3 months compared with no prior anticoagulation ( INR P =0.001; INR ≥2: adjusted odds ratio: 0.40; 95% CI, 0.16–0.97; P =0.043) but was not associated with a lower risk of death or disability at 2 years. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years compared with no prior anticoagulation (adjusted hazard ratio: 2.94; 95% CI, 1.20–6.15; P =0.021). Conclusions Prior warfarin treatment was associated with a lower risk of death or disability at 3 months but was not associated with a lower risk of death or disability at 2 years in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01581502.

Background The aim of this study was to elucidate changes in cerebral white matter after shunt surgery in idiopathic normal pressure hydrocephalus (INPH) using diffusion tensor imaging (DTI). Methods Twenty-eight consecutive INPH patients whose symptoms were followed for 1 year after shunt placement and 10 healthy control (HC) subjects were enrolled. Twenty of the initial 28 INPH patients were shunt-responsive (SR) and the other 8 patients were non-responsive (SNR). The cerebral white matter integrity was detected by assessing fractional anisotropy (FA) and mean diffusivity (MD). The mean hemispheric DTI indices and the ventricular sizes were calculated, and a map of these DTI indices was created for each subject. The DTI maps were analysed to compare preshunt INPH with HC and preshunt INPH with 1 year after shunt placement in each INPH group, using tract-based spatial statistics. We restricted analyses to the left hemisphere because of shunt valve artefacts. Results The ventricles became significantly smaller after shunt placement both in the SR and SNR groups. In addition, there was a significant interaction between clinical improvement after shunt and decrease in ventricular size. Although the hemispheric DTI indices were not significantly changed after shunt placement, there was a significant interaction between clinical improvement and increase in hemispheric MD. Compared with the HC group, FA in the corpus callosum and in the subcortical white matter of the convexity and the occipital cortex was significantly lower in SR at baseline, whereas MD in the periventricular and peri-Sylvian white matter was significantly higher in the SR group. Compared with the pre-operative images, the post-operative FA was only decreased in the corona radiata and only in the SR group. There were no significant regions in which DTI indices were altered after shunt placement in the SNR group. Conclusions Brain white matter regions in which FA was decreased after shunt placement were in the corona radiata between the lateral ventricles and the Sylvian fissures. This finding was observed only in shunt-responsive INPH patients and might reflect the plasticity of the brain for mechanical pressure changes from the cerebrospinal fluid system. Electronic supplementary material The online version of this article (doi:10.1186/s12987-016-0048-8) contains supplementary material, which is available to authorized users.

Recent evidence suggests that patients with Alzheimer's disease (AD), as compared with normal individuals, exhibit increased false recognition by stimulus repetition in the Deese-Roediger-McDermott (DRM) task or associative recognition memory tasks, probably due to impaired recollection-based monitoring. However, because of possible alternative explanations for the findings of these previous studies, the evidence for impaired recollection-based monitoring in AD patients remains inconclusive. In this study, we employed stimulus repetition in old/new recognition judgments of single-item picture memory without a factor of association between the stimuli and examined whether AD patients showed increased false item recognition as compared with healthy controls. AD patients and healthy controls studied single-item pictures presented either once or three times. They were later asked to make an old/new recognition judgment in response to (a) Same pictures, pictures identical to those seen at encoding, (b) Similar lures, novel pictures similar to but not identical to those seen at encoding, and (c) Dissimilar lures, novel pictures not similar to those seen at encoding. For Same pictures, repeated presentation of stimuli increased the proportion of "old" responses in both groups. For Similar lures, repeated presentation of stimuli increased the rate of "old" responses in AD patients but not in control subjects. The results of the present study clearly demonstrated elevated false recognition by stimulus repetition in single-item recognition in AD patients. The present findings strongly support the view that AD patients are impaired in their ability to use item-specific recollection in order to avoid false recognition.

Dissociative amnesia usually follows a stressful event and cannot be attributable to explicit brain damage. It is thought to reflect a reversible deficit in memory retrieval probably due to memory repression. However, the neural mechanisms underlying this condition are not clear. We used fMRI to investigate neural activity associated with memory retrieval in two patients with dissociative amnesia. For each patient, three categories of face photographs and three categories of people's names corresponding to the photographs were prepared: those of “recognizable” high school friends who were acquainted with and recognizable to the patients, those of “unrecognizable” colleagues who were actually acquainted with but unrecognizable to the patients due to their memory impairments, and “control” distracters who were unacquainted with the patients. During fMRI, the patients were visually presented with these stimuli and asked to indicate whether they were personally acquainted with them. In the comparison of the unrecognizable condition with the recognizable condition, we found increased activity in the pFC and decreased activity in the hippocampus in both patients. After treatment for retrograde amnesia, the altered pattern of brain activation disappeared in one patient whose retrograde memories were recovered, whereas it remained unchanged in the other patient whose retrograde memories were not recovered. Our findings provide direct evidence that memory repression in dissociative amnesia is associated with an altered pattern of neural activity, and they suggest the possibility that the pFC has an important role in inhibiting the activity of the hippocampus in memory repression.

Gait disturbance is the most common symptom in idiopathic normal-pressure hydrocephalus (iNPH). However, its pathophysiology in iNPH has not been clarified. Some researchers have hypothesized that the mesencephalic locomotor region, which is a functionally defined area in the brainstem playing an important role in locomotion, is involved in the development of gait disturbance in iNPH. The purpose of the study was to investigate whether the midbrain is involved in the manifestation of gait disturbance in iNPH. Twenty-one iNPH patients who showed clinical improvements after shunt surgery were studied. Brain magnetic resonance imaging (MRI) was performed and clinical symptoms were assessed before and 1 year after surgery. Gait disturbance was assessed by the Timed Up and Go test and gait subcategory of the iNPH Grading Scale, a validated assessment tool for iNPH symptoms. Anteroposterior, left-to-right diameter and cross-sectional areas of the midbrain were measured at the inferior collicular level of axial images in MRI. The diameters and cross-sectional area of the midbrain at baseline did not show significant correlation with gait assessments at baseline (Spearman’s correlation). The midbrain measurement did not show significant difference between the baseline and postoperative values (paired t test), and its change rates did not show significant correlation with the change (rates) of the gait assessments. In this study there were no findings to suggest involvement of the midbrain in the manifestation of gait disturbance in iNPH. The hypothesis that the mesencephalic locomotor region is involved in the manifestation of gait disturbance in iNPH needs to be reconsidered.

To investigate volumetric changes of the brain and cerebrospinal fluid (CSF) spaces after shunt surgery in shunt-responsive idiopathic normal-pressure hydrocephalus (iNPH), and correlations between the changes and postoperative clinical improvements.Twenty-one patients with shunt-responsive iNPH were studied. Magnetic resonance imaging (MRI) of the brain was performed before and 1year after surgery, and clinical symptoms were assessed by the iNPH Grading Scale, a validated assessment tool of the triad of iNPH, the Modified Rankin Scale, the Timed Up and Go Test, and neuropsychological tests including the Mini-Mental State Examination. The volumes of the left cerebral hemisphere, infratentorial brain, ventricles, and suprasylvian and infrasylvian subarachnoid CSF spaces were measured using an MRI-based volumetric technique.The volumes of the cerebral hemisphere and infratentorial brain did not change significantly after shunt surgery (p=0.231, 0.109, respectively). The volumes of the ventricles and infrasylvian subarachnoid CSF spaces were significantly decreased (p0.0001,0.05, respectively), with a mean change rate of -26.1% and -4.5%, respectively. The volumes of the suprasylvian subarachnoid CSF spaces increased significantly (p0.0001), with a mean change rate of 43.5%. The decrease in ventricular volumes was significantly correlated with clinical improvement.

A patient with distal myopathy with rimmed vacuoles (DMRV) exhibited Parkinsonism with a severe writing tremor that responded poorly to levodopa. Molecular genetic analysis revealed that the patient had the D176V/V572L compound heterozygous mutation in the UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) gene. Histopathological examination of a biopsied muscle specimen yielded findings compatible with those of DMRV, which is characterized by the presence of rimmed vacuoles without inflammatory cell infiltration in muscle fibers. The finding of normal cardiac meta-iodobenzylguanide uptake makes the possibility of incidental Parkinson's disease in this patient unlikely. These observations raise the possibility that atypical Parkinsonism is a rare complication of DMRV associated with GNE mutation.