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Contains fulltext : 208767.pdf (publisher's version ) (Open Access), We organized 10Kin1day, a pop-up scientific event with the goal to bring together neuroimaging groups from around the world to jointly analyze 10,000+ existing MRI connectivity datasets during a 3-day workshop. In this report, we describe the motivation and principles of 10Kin1day, together with a public release of 8,000+ MRI connectome maps of the human brain.

Contains fulltext : 199999.pdf (publisher's version ) (Open Access), BACKGROUND AND PURPOSE: Patients with moyamoya vasculopathy (MMV) may experience cognitive impairment, but its reported frequency, severity, and nature vary. In a systematic review and metaanalysis, we aimed to assess the presence, severity, and nature of cognitive impairments in children and adults with MMV. METHODS: We followed the MOOSE guidelines for meta-analysis and systematic reviews of observational studies. We searched Ovid Medline and Embase for studies published between January 1, 1969 and October 4, 2016. Independent reviewers extracted data for mean intelligence quotient (IQ) and standardized z-scores for cognitive tests, and determined percentages of children and adults with cognitive deficits, before and after conservative or surgical treatment. We explored associations between summary measures of study characteristics and cognitive impairments by linear regression analysis. RESULTS: We included 17 studies (11 studies reporting on 281 children, six on 153 adults). In children, the median percentage with impaired cognition was 30% (range, 13% to 67%); median IQ was 98 (range, 71 to 107). Median z-score was -0.39 for memory, and -0.43 for processing speed. In adults, the median percentage with impaired cognition was 31% (range, 0% to 69%); median IQ was 95 (range, 94 to 99). Median z-scores of cognitive domains were between -0.9 and -0.4, with multiple domains being affected. We could not identify determinants of cognitive impairment. CONCLUSION: s A large proportion of children and adults with MMV have cognitive impairment, with modest to large deficits across various cognitive domains. Further studies should investigate determinants of cognitive deficits and deterioration, and the influence of revascularization treatment on cognitive functioning.

Mutations in SCN2A, a gene encoding the voltage-gated sodium channel Nav1.2, have been associated with a spectrum of epilepsies and neurodevelopmental disorders. Here, we report the phenotypes of 71 patients and review 130 previously reported patients. We found that (i) encephalopathies with infantile/childhood onset epilepsies (≥3 months of age) occur almost as often as those with an early infantile onset (<3 months), and are thus more frequent than previously reported; (ii) distinct phenotypes can be seen within the late onset group, including myoclonic-atonic epilepsy (two patients), Lennox-Gastaut not emerging from West syndrome (two patients), and focal epilepsies with an electrical status epilepticus during slow sleep-like EEG pattern (six patients); and (iii) West syndrome constitutes a common phenotype with a major recurring mutation (p.Arg853Gln: two new and four previously reported children). Other known phenotypes include Ohtahara syndrome, epilepsy of infancy with migrating focal seizures, and intellectual disability or autism without epilepsy. To assess the response to antiepileptic therapy, we retrospectively reviewed the treatme

Item does not contain fulltext, BACKGROUND: The pathogenesis of moyamoya disease (MMD) is still unknown. The detection of inflammatory molecules such as cytokines, chemokines and growth factors in MMD patients' biological fluids supports the hypothesis that an abnormal angiogenesis is implicated in MMD pathogenesis. However, it is unclear whether these anomalies are the consequences of the disease or rather causal factors as well as these mechanisms remain insufficient to explain the pathophysiology of MMD. The presence of a family history in about 9-15% of Asian patients, the highly variable incidence rate between different ethnic and sex groups and the age of onset support the role of genetic factors in MMD pathogenesis. However, although some genetic loci have been associated with MMD, few of them have been replicated in independent series. Recently, RNF213 gene was shown to be strongly associated with MMD occurrence with a founder effect in East Asian patients. However, the mechanisms leading from RNF213 mutations to MMD clinical features are still unknown. SUMMARY: The research on pathogenic mechanism of MMD is in its infancy. MMD is probably a complex and heterogeneous disorder, including different phenotypes and genotypes, in which more than a single factor is implicated. KEY MESSAGE: Since the diagnosis of MMD is rapidly increasing worldwide, the development of more efficient stratifying risk systems, including both clinical but also biological drivers became imperative to improve our ability of predict prognosis and to develop mechanism-tailored interventions.

Item does not contain fulltext, PURPOSE: Moyamoya vasculopathy progressively compromises cerebral blood flow resulting in chronic hypoperfusion. The middle cerebral artery (MCA) territory and the bifrontal areas are the regions most frequently affected. Although most techniques aim to only revascularize the MCA territory, augmentation of blood flow of the bifrontal areas is of importance in the pediatric moyamoya population since these regions play an important role in cognition, intellectual development, and in lower extremity and sphincter function. We recently described a one-staged surgical procedure combining revascularization of three regions, the MCA territory unilaterally and the frontal areas bilaterally. The purpose of this article is to report our surgical experience in eight children and to emphasize the rational for bifrontal revascularization. METHODS: We report a case series consisting of eight children where the following surgical strategy was applied: (1) a direct superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass with encephalo-duro-myo-synangiosis (EDMS) for unilateral MCA revascularization; in combination with (2) a bifrontal encephalo-duro-periosteal-synangiosis (EDPS) for bifrontal revascularization. Patients' characteristics and 30-day follow-up data are reported. RESULTS: The patient group consisted of six girls and two boys (mean age 10.0, range 4.2-17.5 years): six children presented with moyamoya disease, two with moyamoya syndrome. We performed a one-staged revascularization of one MCA territory and both frontal areas in all patients. No significant complications occurred. Two patients experienced postoperative focal seizures, successfully treated with anti-epileptic medication. CONCLUSIONS: The single-staged STA-MCA bypass with EDMS combined with bifrontal EDPS allowed revascularization of three regions (the MCA territory unilaterally and the frontal areas bilaterally) and may serve as an alternative and safe treatment option for pediatric moyamoya

Item does not contain fulltext, BACKGROUND: Little is known about cerebral blood flow (CBF) in young patients with ischemic stroke caused by an intracranial arteriopathy. Arterial spin labeling (ASL) perfusion is a noninvasive technique for measuring CBF. We aimed to investigate whether, in young patients with unilateral intracranial arteriopathy and previous ischemic stroke, CBF is compromised in noninfarcted brain areas of the symptomatic hemisphere and whether this is related to the severity of the arteriopathy. METHODS: Patients aged 5-50 years, with previous middle cerebral artery (MCA) territory infarction and a unilateral intracranial arteriopathy, underwent magnetic resonance imaging (MRI), MR angiography and pseudocontinuous ASL perfusion MRI. We assessed the severity of stenosis of arteries that fed the symptomatic MCA territory, quantified CBF in the noninfarcted cortex of both MCA territories and generated CBF maps for visual CBF interpretation. RESULTS: A total of 17 patients were included (median age 29 years, range 5-49, 29% male). We found a similar median quantified CBF in the symptomatic and asymptomatic MCA territories (86 ml.100 g(-1).min(-1)). CBF maps showed hypoperfusion in the symptomatic MCA territory in 59% of patients compared to 18% based on quantified CBF. Patients with a severe arteriopathy more often showed hypoperfusion on CBF maps than patients with a mild arteriopathy. In 53% of patients, small foci of increased signal intensity were visible on CBF maps around an area of hypoperfusion, indicating vascular artifacts. In these patients, we found large intraindividual variation in the quantified CBF in the symptomatic hemisphere. In 47% of patients, the visual interpretation of perfusion did not correspond with the quantified CBF. CONCLUSIONS: This study shows that more than half of young patients with previous ischemic stroke in the MCA territory and a unilateral intracranial arteriopathy have hypoperfusion in the noninfarcted cortex of the symptomatic hemisphere wh

Item does not contain fulltext, Moyamoya disease is a progressive intracranial arteriopathy characterized by bilateral stenosis of the distal portion of the internal carotid artery and the proximal anterior and middle cerebral arteries, resulting in transient ischemic attacks or strokes. The pathogenesis of moyamoya disease remains unresolved, but recent advances have suggested exciting new insights into a genetic contribution as well as into other pathophysiological mechanisms. Treatment that may halt progression of the disease or even reverse the intracranial arteriopathy is yet to be found. There are strong indications that neurosurgical intervention, through direct, indirect, or combined revascularization surgery, can reduce the risk of ischemic stroke and possibly also cognitive dysfunction by improving cerebral perfusion, although randomized clinical trials have not been performed. Many questions regarding the indication for and timing of surgery remain unanswered. In this review, we discuss recent developments in the pathogenesis and treatment of moyamoya disease.

Item does not contain fulltext, Prediction of functional motor outcome after hemispherectomy is difficult due to the heterogeneity of motor outcomes observed. We hypothesize that this might be related to differences in plasticity during the onset of the underlying epileptogenic disorder or lesion and try to identify predictors of motor outcome after hemispherectomy. Thirty-five children with different etiologies (developmental, stable acquired or progressive) underwent functional hemispherectomy and motor function assessment before hemispherectomy and 24 months after hemispherectomy. Preoperatively, children with developmental etiologies performed better in terms of distal arm strength and hand function, but not on gross motor function tests. Postoperatively, the three etiology groups performed equally poor in muscle strength and hand function, but gross motor function improved in those with acquired and progressive etiologies. Loss of voluntary hand function and distal arm strength after surgery was associated with etiology, intact insular cortex and intact structural integrity of the ipsilesional corticospinal tract on presurgical MRI scans. In conclusion, postoperative motor function can be predicted more precisely based on etiology and on preoperative MRI. Children with developmental etiology more often lose distal arm strength and hand function and show less improvement in gross motor function, compared to those with acquired pathology.

Item does not contain fulltext, Diagnosing ischaemic stroke in children is often difficult. Post-varicella angiopathy (PVA) is a well-recognised and frequent cause of childhood ischaemic stroke, particularly affecting the basal ganglia. When a previously healthy child presents with unilateral abnormal involuntary movements, cerebral infarction should be included in the differential diagnosis and PVA should be considered, even when there is no recent history of rash and cerebrospinal fluid is normal. Medical history and intracranial vascular imaging are important for early diagnosis and treatment.

Item does not contain fulltext, BACKGROUND AND PURPOSE: Unilateral intracranial focal nonprogressive arteriopathy is often found in children with arterial ischemic stroke. We aimed to investigate the course of unilateral intracranial arteriopathy in young adults. METHODS: We searched the Utrecht Stroke Database for patients between 16 and 50 years of age diagnosed with anterior circulation arterial ischemic stroke and a nonatherosclerotic, unilateral intracranial large-artery arteriopathy between 1991 and 2005. We assessed clinical features, potential causes, risk factors, extent of infarction and arteriopathy at presentation, long-term angiographic course, and clinical outcome. RESULTS: Of 356 patients with anterior circulation arterial ischemic stroke, 17 (5%) had a documented unilateral intracranial arteriopathy, of whom 14 could be included for follow-up investigations (median age, 34 years; range, 27-49 years). Median duration of follow-up was 8.8 years (range, 1.7-12.8 years). In 11 patients, onset of symptoms was not abrupt. The arteriopathy normalized completely in 5 and improved in 3 patients; in none of the patients did the arteriopathy worsen. Two of 14 patients had recurrent symptoms. Ten patients (71%) had a good outcome (modified Rankin Scale score

Item does not contain fulltext, BACKGROUND: Assessment of outcome after childhood stroke is important both for clinical practice and for research purposes. The objective of this study was to compare two frequently used outcome measures. METHODS: In 40 children with arterial ischemic stroke (AIS), dichotomized outcome obtained from the Pediatric Stroke Outcome Measure (PSOM) was compared with a dichotomized modified Rankin Scale (mRS) combined with information on type of school attendance. In addition, we compared dichotomized outcome, obtained from the PSOM and the mRS combined with school attendance, with the results of pediatric quality of life (PedsQL) questionnaires and the impressions of the child's general functioning on a visual analogue scale (VAS) that was filled out by parents and investigators. RESULTS: In 35 children (88%), outcome classification was concordant between the two outcome measures. Five children had a poor outcome according to the PSOM and good outcome with the mRS including school performance. In these patients, mRS outcome classification agreed better with the impression of the investigators, as reflected by VAS scores >/=7.5. For both the PSOM and mRS in combination with school performance, patients with a good outcome had significantly higher PedsQL and VAS scores than those with a poor outcome (p values <0.01 for all comparisons). VAS scores of investigators and parents correlated significantly with PedsQL. CONCLUSIONS: In children with AIS, both PSOM and mRS combined with school type correlated significantly with quality of life and VAS scores of general functioning. The mRS combined with school type is easier to obtain than the PSOM, reflects function rather than deficits, includes an important measure of cognitive outcome, and corresponds better with the doctor's impression of outcome.

Epilepsy is a disabling neurological disorder, affecting both children and adults. Up until the introduction of MRI, epilepsy has always been considered as a disease of gray matter. Consequently, white matter defects in epilepsy have received little attention. Especially the investigation of white matter in children with epilepsy is essential, as white matter maturation continuous until late adolescents and white matter damage could possibly disturb this maturation process. The aim of this thesis was to obtain a better insight into white matter maturation and disturbances of white matter in children and adolescents with partial epilepsy. The majority of the studies discussed in this thesis reported a lack of white matter volume increase with age in children with partial epilepsy and decreased white matter volumes in adults with partial epilepsy. Furthermore in both children and adolescents decreased FA values, increased perpendicular diffusivity and increased mean diffusivity in a variety of white matter tracts, have been found. These diffusion abnormalities seem irreversible, as they persist after seizure control. The exact meaning of these diffusion disturbances are still unknown, however, myelin or axon abnormalities are being suggested.

Contains fulltext : 57331.pdf (publisher's version ) (Closed access), We report two siblings with a mitochondrial respiratory chain defect who presented with progressive bulbar paralysis of childhood (Fazio-Londe disease). Mitochondrial respiratory chain defects should be considered in differential diagnosis of this rare clinical entity.