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1.  New Insights into Pathophysiology of Vestibular Migraine 
Vestibular migraine (VM) is a common disorder in which genetic, epigenetic, and environmental factors probably contribute to its development. The pathophysiology of VM is unknown; nevertheless in the last few years, several studies are contributing to understand the neurophysiological pathways involved in VM. The current hypotheses are mostly based on the knowledge of migraine itself. The evidence of trigeminal innervation of the labyrinth vessels and the localization of vasoactive neuropeptides in the perivascular afferent terminals of these trigeminal fibers support the involvement of the trigemino-vascular system. The neurogenic inflammation triggered by activation of the trigeminal-vestibulocochlear reflex, with the subsequent inner ear plasma protein extravasation and the release of inflammatory mediators, can contribute to a sustained activation and sensitization of the trigeminal primary afferent neurons explaining VM symptoms. The reciprocal connections between brainstem vestibular nuclei and the structures that modulate trigeminal nociceptive inputs (rostral ventromedial medulla, ventrolateral periaqueductal gray, locus coeruleus, and nucleus raphe magnus) are critical to understand the pathophysiology of VM. Although cortical spreading depression can affect cortical areas involved in processing vestibular information, functional neuroimaging techniques suggest a dysmodulation in the multimodal sensory integration and processing of vestibular and nociceptive information, resulting from a vestibulo-thalamo-cortical dysfunction, as the pathogenic mechanism underlying VM. The elevated prevalence of VM suggests that multiple functional variants may confer a genetic susceptibility leading to a dysregulation of excitatory–inhibitory balance in brain structures involved in the processing of sensory information, vestibular inputs, and pain. The interactions among several functional and structural neural networks could explain the pathogenic mechanisms of VM.
PMCID: PMC4319397
migraine; aura; vertigo; multisensory integration; vestibulo-thalamo-cortical system; Meniere’s disease; vestibular system
2.  Arm and Hand Movement: Current Knowledge and Future Perspective 
PMCID: PMC4319398
reaching; grasping; arm and hand movement; neuromuscular dysfunction; reach-to-grasp; motor control of movement
3.  Biopersistence and Brain Translocation of Aluminum Adjuvants of Vaccines 
Aluminum oxyhydroxide (alum) is a crystalline compound widely used as an immunological adjuvant of vaccines. Concerns linked to the use of alum particles emerged following recognition of their causative role in the so-called macrophagic myofasciitis (MMF) lesion detected in patients with myalgic encephalomyelitis/chronic fatigue/syndrome. MMF revealed an unexpectedly long-lasting biopersistence of alum within immune cells in presumably susceptible individuals, stressing the previous fundamental misconception of its biodisposition. We previously showed that poorly biodegradable aluminum-coated particles injected into muscle are promptly phagocytosed in muscle and the draining lymph nodes, and can disseminate within phagocytic cells throughout the body and slowly accumulate in brain. This strongly suggests that long-term adjuvant biopersistence within phagocytic cells is a prerequisite for slow brain translocation and delayed neurotoxicity. The understanding of basic mechanisms of particle biopersistence and brain translocation represents a major health challenge, since it could help to define susceptibility factors to develop chronic neurotoxic damage. Biopersistence of alum may be linked to its lysosome-destabilizing effect, which is likely due to direct crystal-induced rupture of phagolysosomal membranes. Macrophages that continuously perceive foreign particles in their cytosol will likely reiterate, with variable interindividual efficiency, a dedicated form of autophagy (xenophagy) until they dispose of alien materials. Successful compartmentalization of particles within double membrane autophagosomes and subsequent fusion with repaired and re-acidified lysosomes will expose alum to lysosomal acidic pH, the sole factor that can solubilize alum particles. Brain translocation of alum particles is linked to a Trojan horse mechanism previously described for infectious particles (HIV, HCV), that obeys to CCL2, signaling the major inflammatory monocyte chemoattractant.
PMCID: PMC4318414
alum; vaccine adjuvants; macrophagic myofasciitis; neurotoxicity; genetics; monocytes; CCL2; MCP1
4.  Dissociation of Pupillary Post-Illumination Responses from Visual Function in Confirmed OPA1 c.983A > G and c.2708_2711delTTAG Autosomal Dominant Optic Atrophy 
Purpose: To test whether the melanopsin-containing, intrinsically photosensitive retinal ganglion cells (ipRGCs), as evaluated by examination of the pupillary light reflex (PLR), are preserved in genetically confirmed autosomal dominant optic atrophy (ADOA).
Method: Twenty-nine patients with either the c.983A > G (n = 14) or the c.2708_ 2711delTTAG mutation (n = 15) were examined with monochromatic pupillometry, using isoluminant (300 cd/m2), red (660 nm) or blue (470 nm) light, optical coherence tomography, automated visual field analysis, and with determination of best corrected visual acuity (BCVA). Since we examined two different mutations, initially we compared all outcome variables between the two, and finding no statistically significant difference, pooled them.
Results: Despite a poor BCVA (56 letters, ETDRS) in the ADOA patients, their post-illuminatory pupil responses did not differ significantly from those of healthy controls (blue, p = 0.45, red, p = 0.49, t-test), and no statistically significant effect was noted of peripapillary retinal nerve fiber layer thickness, ganglion cell-inner plexiform layer thickness, or age.
Conclusion: The PLR to blue light of high luminance (300 cd/m2) was preserved in both c.983A > G and c.2708_2711delTTAG ADOA despite severe visual loss and optic nerve atrophy. The study confirms, in a large sample of two genetically homogenous groups, that the ipRGCs are spared in ADOA.
PMCID: PMC4316714
autosomal dominant optic atrophy; pupillary light reflex; melanopsin; intrinsically photosensitive retinal ganglion cells; ipRGC
5.  Efficacy and Tolerability of STOPAIN for a Migraine Attack 
Objective: To determine whether topical menthol 6% gel will relieve a migraine attack.
Materials and Methods: A single-center, open-label pilot trial of 25 patients with at least 1 year of diagnosed episodic migraine and <15 headache days per month. Patients treated one migraine attack with STOPAIN topical menthol 6% gel to skull base within 2 h of headache onset. Headache pain severity was assessed prior to and after gel application.
Results: Thirty-two patients enrolled and 25 completed the study. Prior to treatment, 7 patients had mild pain, 13 moderate pain, and 5 severe pain. Two hours following gel application, 7 (28%) patients had no pain, 7 (28%) mild pain, 6 (25%) moderate pain, and 5 (20%) severe pain. The majority of patients had similar pain intensity (8; 32%) or improvement (13; 52%). At 24-h, only two non-rescued patients still had mild headache. Of the 25 completers, 2 patients took rescue medication prior to the 2-h period, and an additional 10 patients rescued between 2 and 24 h.
Conclusion: Study results showed a significant improvement in headache intensity by 2 h after gel application. This pilot study shows STOPAIN gel may be effective in treating an acute migraine attack.
PMCID: PMC4316718
acute migraine; acute migraine treatment; topical treatment; headache; migraine
6.  Is Personality Profile a Relevant Determinant of Fatigue in Multiple Sclerosis? 
The origin and pathophysiological background of multiple sclerosis (MS)-associated fatigue is poorly understood. There is no unifying concept of its nature and its determinants to date. This paper reviews possible influences of factors determining personality profile on fatigue in MS. Likewise, the role of psychological factors and their interaction with personality to promote fatigue is discussed. Current data suggest that fatigue, especially in early MS states, may be influenced by vulnerable personality traits and personality-associated features. Among them are depressive disease coping, avoidance behavior and inhibition, irritability, less extraversion, neuroticism, lower reward responsiveness, and somatization behavior. However, among the validated personality factors, no genuine influences that are independent of depression have been documented. From a psychological perspective, depressiveness, anxiety, and somatization may be relevant mediators of fatigue. Interesting to note that in early MS, a psychiatric diagnosis is significantly more likely than on a later stage of the disease and that fatigue and motivation might share neural circuits. It is hypothesized that psychological factors promote fatigue in MS by psychological distress and sustained neuroendocrine and neurovegetative stress response. Despite the limitations of data discussed in the paper, personality research might help to disentangle specific promoting factors of fatigue in MS. Further research efforts are warranted since they might open ways to early psychological intervention of MS-associated fatigue. This is all the more important since medication is insufficient until now.
PMCID: PMC4316719
multiple sclerosis; fatigue; personality assessment; depression; coping behavior; anxiety
7.  Changing Shapes of Glycogen–Autophagy Nexus in Neurons: Perspective from a Rare Epilepsy 
In brain, glycogen metabolism is predominantly restricted to astrocytes but it also indirectly supports neuronal functions. Increased accumulation of glycogen in neurons is mysteriously pathogenic triggering neurodegeneration as seen in “Lafora disease” (LD) and in other transgenic animal models of neuronal glycogen accumulation. LD is a fatal neurodegenerative disorder with excessive glycogen inclusions in neurons. Autophagy, a pathway for bulk degradation of obsolete cellular constituents also degrades metabolites like lipid and glycogen. Recently, defects in this pathway emerged as a plausible reason for glycogen accumulation in neurons in LD, although some contradictions prevail. Albeit surprising, a reciprocal regulation of autophagy by glycogen in neurons has also just been proposed. Notably, increasing evidences of interaction between proteins of autophagy and glycogen metabolism from diverse model systems indicate a conserved, dynamic, and regulatory cross-talk between these two pathways. Concerning these findings, we herein provide certain models for the molecular basis of this cross-talk and discuss its potential implication in the pathophysiology of LD.
PMCID: PMC4316721
autophagy; glycogen; polyglucosan; neurodegeneration; Lafora disease
8.  Mechanism of Action of Acetazolamide and Idiopathic Intracranial Hypertension 
PMCID: PMC4315016
carbonic anhydrase; acetazolamide; idiopathic intracranial hypertension; pharmacology; papilledema
9.  Consequences of Traumatic Brain Injury for Human Vergence Dynamics 
Purpose: Traumatic brain injury involving loss of consciousness has focal effects in the human brainstem, suggesting that it may have particular consequences for eye movement control. This hypothesis was investigated by measurements of vergence eye movement parameters.
Methods: Disparity vergence eye movements were measured for a population of 123 normally sighted individuals, 26 of whom had suffered diffuse traumatic brain injury (dTBI) in the past, while the remainder served as controls. Vergence tracking responses were measured to sinusoidal disparity modulation of a random-dot field. Disparity vergence step responses were characterized in terms of their dynamic parameters separately for the convergence and divergence directions.
Results: The control group showed notable differences between convergence and divergence dynamics. The dTBI group showed significantly abnormal vergence behavior on many of the dynamic parameters.
Conclusion: The results support the hypothesis that occult injury to the oculomotor control system is a common residual outcome of dTBI.
PMCID: PMC4315029
oculomotor dynamics; vergence; binocular eye movements; convergence; divergence; traumatic brain injury
10.  The Case for Diet: A Safe and Efficacious Strategy for Secondary Stroke Prevention 
Diet is strongly associated with risk for first stroke. In particular, observational and experimental research suggests that a Mediterranean-type diet may reduce risk for first ischemic stroke with an effect size comparable to statin therapy. These data for first ischemic stroke suggest that diet may also be associated with risk for recurrent stroke and that diet modification might represent an effective intervention for secondary prevention. However, research on dietary pattern after stroke is limited and direct experimental evidence for a therapeutic effect in secondary prevention does not exist. The uncertain state of science in this area is reflected in recent guidelines on secondary stroke prevention from the American Heart Association, in which the Mediterranean-type diet is listed with only a class IIa recommendation (level of evidence C). To change guidelines and practice, research is needed, starting with efforts to better define current nutritional practices of stroke patients. Food frequency questionnaires and mobile applications for real-time recording of intake are available for this purpose. Dietary strategies for secondary stroke prevention are low risk, high potential, and warrant further evaluation.
PMCID: PMC4313694
diet; secondary prevention stroke; dietary patterns; m-health
11.  Hormonal Contraceptives and Cerebral Venous Thrombosis Risk: A Systematic Review and Meta-Analysis 
Objectives: Use of oral contraceptive pills (OCP) increases the risk of cerebral venous sinus thrombosis (CVST). Whether this risk varies by type, duration, and other forms of hormonal contraceptives is largely unknown. This systematic review and meta-analysis update the current state of knowledge.
Methods: We performed a search to identify all published studies on the association between hormonal contraceptive use and risk of CVST in women aged 15–50 years.
Results: Of 861 studies reviewed, 11 were included. The pooled odds of developing CVST in women aged 15–50 years taking OCPs was 7.59 times higher compared to women not taking OCPs (OR = 7.59, 95% CI 3.82–15.09). Data are insufficient to make conclusions about duration of use and other forms of hormonal contraceptives.
Conclusion: Oral contraceptive pills use increases the risk of developing CVST in women of reproductive age. Future studies are required to determine if duration and type of hormonal contraceptives modify this risk.
PMCID: PMC4313700
hormonal contraceptives; birth control pill; oral contraceptive pill; cerebral venous sinus thrombosis; cerebral venous thrombosis
12.  Early Administration of Therapeutic Anticoagulation Following Intravenous Thrombolysis for Acute Cardiogenic Embolic Stroke Caused by Left Ventricular Thrombus: Case Report and Topic Review 
Cardiogenic cerebral embolism represents 20% of all acute ischemic strokes (AISs) with one-third of these being caused by left ventricular thrombus (LVT). LVT is not a contraindication for treatment with intravenous recombinant tissue plasminogen activator (IV rtPA) for AIS. However, the subsequent treatment of a potentially unstable LVT is contraindicated for 24 h following the use of IV rtPA according to current guidelines. We present a 66-year-old man with AIS treated with IV rtPA. Echocardiogram shortly after treatment demonstrated both a large apical and septal thrombus in the left ventricle and at 12 h post IV rtPA infusion, therapeutic anticoagulation with heparin was started without complication. In practice, the action of IV rtPA outlasts its apparent half-life because of thrombin-binding and the prolonged effects and longer half-life of its product, plasmin; however, the pharmacokinetics do not warrant prolonged avoidance of therapeutic anticoagulation when clinically indicated. Our case demonstrates that anticoagulation for potentially unstable LVT can be safely initiated at 12 h following IV rtPA treatment for AIS.
PMCID: PMC4313703
acute ischemic stroke; cardioembolic; thrombolysis; left ventricular thrombus; anticoagulation; rtPA; alteplase; pharmacokinetics
13.  Management of Super-Refractory Status Epilepticus with Isoflurane and Hypothermia 
Super-refractory status epilepticus (SRSE) is defined as status epilepticus that continues 24 h or more after the onset of anesthesia, and includes those cases in which epilepsy is recurrent upon treatment reduction. We describe the presentation and successful management of a male patient with SRSE using the inhaled anesthetic isoflurane, and mild hypothermia (HT). The potential utility of combined HT and volatile anesthesia is discussed.
PMCID: PMC4309114
SRSE; epilepsy; hypothermia; isoflurane; neurotrauma; neurocritical care
15.  Vestibular Migraine in Children and Adolescents: Clinical Findings and Laboratory Tests 
Introduction: Vestibular migraine (VM) is the most common cause of episodic vertigo in children. We summarize the clinical findings and laboratory test results in a cohort of children and adolescents with VM. We discuss the limitations of current classification criteria for dizzy children.
Methods: A retrospective chart analysis was performed on 118 children with migraine related vertigo at a tertiary care center. Patients were grouped in the following categories: (1) definite vestibular migraine (dVM); (2) probable vestibular migraine (pVM); (3) suspected vestibular migraine (sVM); (4) benign paroxysmal vertigo (BPV); and (5) migraine with/without aura (oM) plus vertigo/dizziness according to the International Classification of Headache Disorders, 3rd edition (beta version).
Results: The mean age of all patients was 12 ± 3 years (range 3–18 years, 70 females). 36 patients (30%) fulfilled criteria for dVM, 33 (28%) for pVM, 34 (29%) for sVM, 7 (6%) for BPV, and 8 (7%) for oM. Somatoform vertigo (SV) co-occurred in 27% of patients. Episodic syndromes were reported in 8%; the family history of migraine was positive in 65%. Mild central ocular motor signs were found in 24% (most frequently horizontal saccadic pursuit). Laboratory tests showed that about 20% had pathological function of the horizontal vestibulo-ocular reflex, and almost 50% had abnormal postural sway patterns.
Conclusion: Patients with definite, probable, and suspected VM do not differ in the frequency of ocular motor, vestibular, or postural abnormalities. VM is the best explanation for their symptoms. It is essential to establish diagnostic criteria in clinical studies. In clinical practice, however, the most reasonable diagnosis should be made in order to begin treatment. Such a procedure also minimizes the fear of the parents and children, reduces the need to interrupt leisure time and school activities, and prevents the development of SV.
PMCID: PMC4306301
migraine-related vertigo; vestibular migraine; somatoform vertigo; ocular motor signs
16.  Creative Expression of Science through Poetry and Other Media can Enrich Medical and Science Education 
PMCID: PMC4302945  PMID: 25657637
poetic science; poetry; neurology; neuroscience; education; learning; creativity; STEAM
17.  Diffusion–Perfusion Mismatch: An Opportunity for Improvement in Cortical Function 
Objective: There has been controversy over whether diffusion–perfusion mismatch provides a biomarker for the ischemic penumbra. In the context of clinical stroke trials, regions of the diffusion–perfusion mismatch that do not progress to infarct in the absence of reperfusion are considered to represent “benign oligemia.” However, at least in some cases (particularly large vessel stenosis), some of this hypoperfused tissue may remain dysfunctional for a prolonged period without progressing to infarct and may recover function if eventually reperfused. We hypothesized that patients with persistent diffusion–perfusion mismatch using a hypoperfusion threshold of 4–5.9 s delay on time-to-peak (TTP) maps at least sometimes have persistent cognitive deficits relative to those who show some reperfusion of this hypoperfused tissue.
Methods: We tested this hypothesis in 38 patients with acute ischemic stroke who had simple cognitive tests (naming or line cancelation) and MRI with diffusion and perfusion imaging within 24 h of onset and again within 10 days, most of whom had large vessel stenosis or occlusion.
Results: A persistent perfusion deficit of 4–5.9 s delay in TTP on follow up MRI was associated with a persistent cognitive deficit at that time point (p < 0.001). When we evaluated only patients who did not have infarct growth (n = 14), persistent hypoperfusion (persistent mismatch) was associated with a lack of cognitive improvement compared with those who had reperfused. The initial volume of hypoperfusion did not correlate with the later infarct volume (progression to infarct), but change in volume of hypoperfusion correlated with change in cognitive performance (p = 0.0001). Moreover, multivariable regression showed that the change in volume of hypoperfused tissue of 4–5.9 s delay (p = 0.002), and change in volume of ischemic tissue on diffusion weighted imaging (p = 0.02) were independently associated with change in cognitive function.
Conclusion: Our results provide additional evidence that non-infarcted tissue with a TTP delay of 4–5.9 s may be associated with persistent deficits, even if it does not always result in imminent progression to infarct. This tissue may represent the occasional opportunity to intervene to improve function even days after onset of symptoms.
PMCID: PMC4294157  PMID: 25642208
diffusion–perfusion mismatch; acute ischemic stroke; penumbra; NIHSS; functional outcome
18.  A RCT Comparing Specific Intensive Cognitive Training to Aspecific Psychological Intervention in RRMS: The SMICT Study 
Background: Specific cognitive rehabilitation in multiple sclerosis (MS) resulted to be effective compared to no treatment. So far the possible role of an aspecific psychological intervention on cognition has not been investigated.
Objective: The aim of the SMICT RCT was to compare the efficacy of a specific cognitive training with an aspecific psychological intervention in relapsing-remitting MS patients.
Methods: From a sample of 150 patients, with the same disability and immunomodulatory therapy, submitted to neuropsychological examination, 45 impaired in at least one test were included and 41 randomized to have either a specific cognitive training for the impaired function (22) or to an aspecific psychological intervention (19) for 4 months, starting after baseline examination. Neuropsychological tests and functional scales were administered at baseline and 1 year later.
Results: After 1 year, the mean number of pathological tests was significantly lower in the specific treatment group, compared to the aspecific group. Memory and attention/speeded information processing functions were mostly improved. Depression and quality of life were not different between groups at follow up.
Conclusion: Our study demonstrates that an intensive and domain specific cognitive approach results to be more effective than aspecific psychological intervention in patients with MS.
PMCID: PMC4292447  PMID: 25628596
multiple sclerosis; cognitive rehabilitation; attention; executive functions memory; information processing speed; multiple sclerosis cognitive rehabilitation
19.  The Mammalian Circadian Clock Gene Per2 Modulates Cell Death in Response to Oxidative Stress 
Living in the earth’s oxygenated environment forced organisms to develop strategies to cope with the damaging effects of molecular oxygen known as reactive oxygen species (ROS). Here, we show that Per2, a molecular component of the mammalian circadian clock, is involved in regulating a cell’s response to oxidative stress. Mouse embryonic fibroblasts (MEFs) containing a mutation in the Per2 gene are more resistant to cytotoxic effects mediated by ROS than wild-type cells, which is paralleled by an altered regulation of bcl-2 expression in Per2 mutant MEFs. The elevated survival rate and alteration of NADH/NAD+ ratio in the mutant cells is reversed by introduction of the wild-type Per2 gene. Interestingly, clock synchronized cells display a time dependent sensitivity to paraquat, a ROS inducing agent. Our observations indicate that the circadian clock is involved in regulating the fate of a cell to survive or to die in response to oxidative stress, which could have implications for cancer development and the aging process.
PMCID: PMC4292776  PMID: 25628599
apoptosis; adenovirus; bcl-2; paraquat; plumbagin; UV; SIN-1; p53
20.  Diagnostic Yield of Extended Cardiac Patch Monitoring in Patients with Stroke or TIA 
Background: It is important to evaluate patients with transient ischemic attack (TIA) or stroke for atrial fibrillation (AF) because the detection of AF changes the recommended anti-thrombotic regimen from treatment with an antiplatelet agent to oral anticoagulation. This study describes the diagnostic yield of a patch-based, single-use, and water-resistant 14-day continuous cardiac rhythm monitor (ZIO Patch) in patients with stroke or TIA.
Methods: We obtained data from the manufacturer and servicer of the ZIO Patch (iRhythm Technologies). Patients who were monitored between January 2012 and June 2013 and whose indication for monitoring was TIA or stroke were included. The duration of monitoring, the number and type of arrhythmias, and the time to first arrhythmia were documented.
Results: One thousand one hundred seventy-one monitoring reports were analyzed. The mean monitor wear time was 10.9 days and the median wear time was 13.0 days (interquartile range 7.2–14.0). The median analyzable time relative to the total wear time was 98.7% (IQR 96.0–99.5%). AF was present in 5.0% of all reports. The mean duration before the first episode of paroxysmal AF (PAF) was 1.5 days and the median duration was 0.4 days. 14.3% of first PAF episodes occurred after 48 h. The mean PAF burden was 12.7% of the total monitoring duration.
Conclusion: Excellent quality of the recordings and very good patient compliance coupled with a substantial proportion of AF detection beyond the first 48 h of monitoring suggest that the cardiac patch is superior to conventional 48-h Holter monitors for AF detection in patients with stroke or TIA.
PMCID: PMC4290477  PMID: 25628595
stroke; telemetry; atrial fibrillation; cardiac monitoring; arrhythmias; cardiac; TIA; SVT
21.  When Mars Versus Venus is Not a Cliché: Gender Differences in the Neurobiology of Alzheimer’s Disease 
PMCID: PMC4290582  PMID: 25628598
sex differences; amyloid; hippocampus; biomarkers; treatment
22.  Transient Global Amnesia Associated with a Unilateral Infarction of the Fornix: Case Report and Review of the Literature 
Stroke is an extremely uncommon cause of transient global amnesia (TGA). Unilateral lesions of the fornix rarely cause amnesia and have not previously been reported to be associated with the distinctive amnesic picture of TGA. We describe the case of a 60-year-old woman who presented with acute onset, recent retrograde, and anterograde amnesia characteristic of TGA. Serial magnetic resonance imaging showed a persistent focal infarction of the body and left column of the fornix, without acute lesions in the hippocampus or other structures. Amnesia resolved in 6 h. Infarction of the fornix should thus be included in the differential diagnosis of TGA, as it changes the management of this otherwise self-limited syndrome.
PMCID: PMC4290584  PMID: 25628601
amnesia; transient global; brain infarction; fornix; brain; stroke
23.  lop-DWI: A Novel Scheme for Pre-Processing of Diffusion-Weighted Images in the Gradient Direction Domain 
We describe and evaluate a pre-processing method based on a periodic spiral sampling of diffusion-gradient directions for high angular resolution diffusion magnetic resonance imaging. Our pre-processing method incorporates prior knowledge about the acquired diffusion-weighted signal, facilitating noise reduction. Periodic spiral sampling of gradient direction encodings results in an acquired signal in each voxel that is pseudo-periodic with characteristics that allow separation of low-frequency signal from high frequency noise. Consequently, it enhances local reconstruction of the orientation distribution function used to define fiber tracks in the brain. Denoising with periodic spiral sampling was tested using synthetic data and in vivo human brain images. The level of improvement in signal-to-noise ratio and in the accuracy of local reconstruction of fiber tracks was significantly improved using our method.
PMCID: PMC4290594  PMID: 25628600
spiral sampling; gradient direction domain; diffusion-weighted imaging; pre-processing; HARDI; local reconstruction
24.  Changes in Chronotype after Stroke: A Pilot Study 
This study aimed to elucidate associations between stroke onset and severity as well as chronotype (phase of entrainment) and internal time of stroke. Fifty-six first-ever ischemic stroke patients participated in a cross-sectional study assessing chronotype (mid-sleep on work-free days corrected for sleep deficit on workdays; MSFsc) by applying the Munich ChronoType Questionnaire (MCTQ). The MCTQ was completed twice, on average 68 ± 24 (SD) days post stroke and retrospectively for the time before stroke. To assess the impact of stroke in relation to internal time, InTstroke was calculated as MSFsc minus local time of stroke. Stroke severity was assessed via the standard clinical National Institute Health Stroke Scale (NIHSS) and modified Ranking Scale (mRS), both at hospital admission and discharge. Overall, most strokes occurred between noon and midnight. There was no significant association between MSFsc and stroke onset. MSFsc changed significantly after stroke, especially in patients with more severe strokes. Changes in MSFsc varied with InTstroke – the earlier the internal time of a stroke relative to MSFsc-before-stroke, the more MSFsc advanced after stroke. In addition, we provide first evidence that MSFsc changes varied between stroke locations. Larger trials are needed to confirm these findings.
PMCID: PMC4290616  PMID: 25628597
chronotype; internal time; sleep; stroke; stroke location; NIHSS; mRS
25.  Movement Recognition Technology as a Method of Assessing Spontaneous General Movements in High Risk Infants 
Preterm birth is associated with increased risks of neurological and motor impairments such as cerebral palsy. The risks are highest in those born at the lowest gestations. Early identification of those most at risk is challenging meaning that a critical window of opportunity to improve outcomes through therapy-based interventions may be missed. Clinically, the assessment of spontaneous general movements is an important tool, which can be used for the prediction of movement impairments in high risk infants. Movement recognition aims to capture and analyze relevant limb movements through computerized approaches focusing on continuous, objective, and quantitative assessment. Different methods of recording and analyzing infant movements have recently been explored in high risk infants. These range from camera-based solutions to body-worn miniaturized movement sensors used to record continuous time-series data that represent the dynamics of limb movements. Various machine learning methods have been developed and applied to the analysis of the recorded movement data. This analysis has focused on the detection and classification of atypical spontaneous general movements. This article aims to identify recent translational studies using movement recognition technology as a method of assessing movement in high risk infants. The application of this technology within pediatric practice represents a growing area of inter-disciplinary collaboration, which may lead to a greater understanding of the development of the nervous system in infants at high risk of motor impairment.
PMCID: PMC4288331  PMID: 25620954
preterm birth; cerebral palsy; neuro-motor assessment; general movement assessment; movement recognition

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