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Adam Kirton - One of the best experts on this subject based on the ideXlab platform.

  • Perinatal arterial ischemic Stroke and periventricular venous infarction in infants with unilateral cerebral palsy
    Developmental Medicine & Child Neurology, 2021
    Co-Authors: Melissa Vitagliano, Adam Kirton, Mary Dunbar, Sasha Dyck Holzinger, Nicole Letourneau, Deborah Dewey, Maryam Oskoui, Michael Shevell
    Abstract:

    Aim To explore clinical factors associated with Perinatal arterial ischemic Stroke (AIS) and periventricular venous infarction (PVI) in infants who develop unilateral cerebral palsy (CP). Method This was a case-control study. Data current to 2019 was extracted from the Canadian Cerebral Palsy Registry (CCPR). Cases were infants born at term with confirmed unilateral CP. Magnetic resonance images were stratified by expert review of reports as definitive Perinatal Stroke (AIS or PVI). Controls with common data elements were recruited from a population-based study in Alberta. Multivariable regression analyses were performed to estimate associations expressed as odds ratios with 95% confidence intervals. Results Of 2093 cases from the CCPR, 662 had unilateral CP, of whom 299 (45%) had Perinatal Stroke: AIS 169 (57%) and PVI 130 (43%). Median age at diagnosis for AIS was 11.9 months (interquartile range: 6.2-25.7mo; range 0.17-104.1mo), and 58.6% were male. Median age at diagnosis for PVI was 25.3 months (interquartile range: 14.5-38mo, range 0.7-114.7mo) and 57.7% were male. Independent associations for both AIS and PVI on multivariable analysis were chorioamnionitis, illicit drug exposure, diabetes, gestational age, and maternal age. Variables associated with AIS alone were low Apgar score and prolonged rupture of membranes. Variables associated with PVI alone were small for gestational age and primigravida. Interpretation Controlled analysis of disease-specific unilateral CP may offer unique perspectives on its pathophysiology. Acute intrapartum factors are mainly associated with AIS, while in utero factors are associated with PVI.

  • head circumference trajectory in children with Perinatal Stroke
    Journal of Child Neurology, 2021
    Co-Authors: Amanda Leong, Adam Kirton, Amalia Floer, Aleksandra Mineyko
    Abstract:

    Background:Perinatal Stroke is a leading cause of hemiparetic cerebral palsy and lifelong disability. Neurodevelopmental outcomes are difficult to predict and markers of long-term poor outcome cont...

  • protocol for a cost utility analysis of neurostimulation and intensive camp based therapy for children with Perinatal Stroke and hemiparesis based on a multicentre clinical trial
    BMJ Open, 2021
    Co-Authors: Patrick Berrigan, Adam Kirton, Jacquie Hodge, Myla E Moretti, Wendy J Ungar, Jennifer D Zwicker
    Abstract:

    Introduction Perinatal Stroke leads to cerebral palsy (CP) and lifelong disability for thousands of Canadian children. Hemiparesis, referring to impaired functionality in one side of the body, is a common complication of Perinatal Stroke. Standard long-term care for hemiparetic CP focuses on rehabilitation therapies. Early research suggests that patients with hemiparesis may benefit from adjunctive neuromodulation treatments such as transcranial direct current stimulation (tDCS). tDCS uses electric current to stimulate targeted areas of the brain non-invasively, potentially enhancing the effects of motor learning therapies. This protocol describes an economic evaluation to be conducted alongside a randomised controlled trial (RCT) to assess the incremental cost of tDCS added to a camp-based therapy compared with camp-based therapy alone per quality-adjusted life year (QALY) gained in children with hemiparetic CP. Methods and analysis The Stimulation for Perinatal Stroke Optimising Recovery Trajectories (SPORT) trial is a multicentre RCT evaluating tDCS added to a 2-week camp-based therapy for children aged 6–18 years with Perinatal ischaemic Stroke and disabling hemiparetic CP affecting the upper limb. Outcomes are assessed at baseline, 1 week, 2 months and 6 months following intervention. Cost and quality of life data are collected at baseline and 6 months and results will be used to conduct a cost–utility analysis (CUA). The evaluation will be conducted from the perspectives of the public healthcare system and society. The CUA will be conducted over a 6-month time horizon. Ethics and dissemination Ethical approval for the SPORT trial and the associated economic evaluation has been given by the research ethics boards at each of the study sites. The findings of the economic evaluation will be submitted for publication in a peer reviewed academic journal and submitted for presentation at conference. Trial registration number NCT03216837; Post-results.

  • executive behavior and functional abilities in children with Perinatal Stroke and the associated caregiver impact
    Child Neuropsychology, 2021
    Co-Authors: Muhammad H Khan, Adam Kirton, Jerome Y Yager, Lisa Smithson, Jacqueline Pei, John Andersen, Brian L Brooks
    Abstract:

    Perinatal Stroke is the most common form of Stroke in childhood and is followed by a variety of outcomes, with many children experiencing specific functional and neuropsychological deficits. The association of these outcomes with the psychosocial impact caregivers face is not well documented. The goal of our pilot study was to examine caregivers' perception of executive behavior and functional abilities among children with Perinatal Stroke, and how these outcomes impact the caregivers. We administered three questionnaires to primary caregivers of children with Perinatal Stroke to obtain caregiver-reported measures of (1) executive behavior of their child (Behavior Rating Inventory of Executive Function, Second Edition), (2) the functional abilities of their child (Pediatric Evaluation of Disability Inventory Computer Adaptive Test), and (3) the psychosocial impact experienced by the caregiver themselves (Parental Outcome Measure). Participants included 20 children (mean age = 9.3 years, range = 6-16 years) with Perinatal Stroke and their primary caregivers. Functional abilities in the children were rated as clinically impaired in the domains of daily activities and mobility. Half of the children exhibited clinically impaired ratings on at least one executive behavior domain, but the mean scores for these domains did not reach clinically impaired levels. Greater ratings of problems in daily activities for the child was associated with greater caregiver guilt (r = -0.55, p = 0.02). Caregivers of children with Perinatal Stroke who experience limitations in performing daily activities should be more closely monitored for adverse impact and be provided the necessary support and education to alleviate the associated guilt.

  • developmental remodelling of the motor cortex in hemiparetic children with Perinatal Stroke
    Pediatric Neurology, 2020
    Co-Authors: Kayla Baker, Ephrem Zewdie, Helen L. Carlson, Adam Kirton
    Abstract:

    Abstract Background Perinatal Stroke often leads to lifelong motor impairment. Two common subtypes differ in timing, location, and mechanism of injury: periventricular venous infarcts (PVI) are fetal white matter lesions while most arterial ischemic Strokes (AIS) are cortical injuries acquired near term birth. Both alter motor system development and primary motor cortex (M1) plasticity, often with retained ipsilateral corticospinal fibers from the non-lesioned motor cortex (M1′). Methods Task-based functional magnetic resonance imaging was used to define patterns of motor cortex activity during paretic and unaffected hand movement. Peak coordinates of M1, M1′, and the supplementary motor area in the lesioned and intact hemispheres were compared to age-matched controls. Correlations between displacements and clinical motor function were explored. Results Forty-nine participants included 14 PVI (12.59 ± 3.7 years), 13 AIS (14.91 ± 3.9 years), and 22 controls (13.91 ± 3.4 years). AIS displayed the greatest M1 displacement from controls in the lesioned hemisphere while PVI locations approximated controls. Peak M1′ activations were displaced from the canonical hand knob in both PVI and AIS. Extent of M1 and M1′ displacement were correlated (r = 0.50, P = 0.025) but were not associated with motor function. Supplementary motor area activity elicited by paretic tapping was displaced in AIS compared to controls (P = 0.003). Conclusion Motor network components may be displaced in both hemispheres after Perinatal Stroke, particularly in AIS and those with ipsilateral control of the affected limb. Modest correlations with clinical function may support that more complex models of developmental plasticity are needed to inform targets for individualized neuromodulatory therapies in children with Perinatal Stroke.

Ephrem Zewdie - One of the best experts on this subject based on the ideXlab platform.

  • developmental remodelling of the motor cortex in hemiparetic children with Perinatal Stroke
    Pediatric Neurology, 2020
    Co-Authors: Kayla Baker, Ephrem Zewdie, Helen L. Carlson, Adam Kirton
    Abstract:

    Abstract Background Perinatal Stroke often leads to lifelong motor impairment. Two common subtypes differ in timing, location, and mechanism of injury: periventricular venous infarcts (PVI) are fetal white matter lesions while most arterial ischemic Strokes (AIS) are cortical injuries acquired near term birth. Both alter motor system development and primary motor cortex (M1) plasticity, often with retained ipsilateral corticospinal fibers from the non-lesioned motor cortex (M1′). Methods Task-based functional magnetic resonance imaging was used to define patterns of motor cortex activity during paretic and unaffected hand movement. Peak coordinates of M1, M1′, and the supplementary motor area in the lesioned and intact hemispheres were compared to age-matched controls. Correlations between displacements and clinical motor function were explored. Results Forty-nine participants included 14 PVI (12.59 ± 3.7 years), 13 AIS (14.91 ± 3.9 years), and 22 controls (13.91 ± 3.4 years). AIS displayed the greatest M1 displacement from controls in the lesioned hemisphere while PVI locations approximated controls. Peak M1′ activations were displaced from the canonical hand knob in both PVI and AIS. Extent of M1 and M1′ displacement were correlated (r = 0.50, P = 0.025) but were not associated with motor function. Supplementary motor area activity elicited by paretic tapping was displaced in AIS compared to controls (P = 0.003). Conclusion Motor network components may be displaced in both hemispheres after Perinatal Stroke, particularly in AIS and those with ipsilateral control of the affected limb. Modest correlations with clinical function may support that more complex models of developmental plasticity are needed to inform targets for individualized neuromodulatory therapies in children with Perinatal Stroke.

  • fatigue in children with Perinatal Stroke clinical and neurophysiological associations
    Developmental Medicine & Child Neurology, 2020
    Co-Authors: James G Wrightson, Ephrem Zewdie, Hsingching Kuo, Guillaume Y Millet, Adam Kirton
    Abstract:

    Aim To characterize fatigue in children with hemiparesis with Perinatal Stroke and explore associations with measures of motor performance and corticospinal excitability. Method Forty-five children (16 females, 29 males), aged 6 to 18 years (mean [SD] 12y [4]), with magnetic resonance imaging-confirmed Perinatal Stroke participated. Associations between fatigue (Pediatric Quality of Life Inventory Version 3.0 cerebral palsy module fatigue subscale), motor performance (Assisting Hand Assessment [AHA], Box and Blocks Test, grip strength), and excitability of corticospinal projections to both hands were examined using ranked tests of correlation, robust regression, and the Mann-Whitney U test. Results Nearly half of the participants (n=21) reported experiencing fatigue in the previous month. Function in the less affected hand (Box and Blocks Test, grip strength) was correlated with fatigue scores. Participants with preserved ipsilateral projections to the more affected hand had less fatigue, and scores correlated with the excitability of these projections. Fatigue scores were not associated with age, sex, or AHA score. Interpretation Fatigue is common in children with hemiparesis with Perinatal Stroke and is associated with motor performance and the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere to the more affected hand. What this paper adds Fatigue is common in children with hemiparesis with Perinatal Stroke. Fatigue was associated with motor performance and strength in the less affected, but not the more affected, hand. Fatigue was associated with the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere.

  • mirror movements in children with unilateral cerebral palsy due to Perinatal Stroke clinical correlates of plasticity reorganization
    Developmental Medicine & Child Neurology, 2019
    Co-Authors: Madison Riddell, Hsingching Kuo, Ephrem Zewdie, Adam Kirton
    Abstract:

    Aim We aimed to determine if the mirror movements that often result in children with unilateral cerebral palsy (CP) after Perinatal Stroke represent a clinical biomarker of developmental plasticity. Method This was a prospective, controlled cohort study. Mirror movements in children with unilateral CP from a population-based cohort were compared to those of typically developing controls. The population with Stroke was assessed further via electromyography (EMG), motor function, and corticospinal organization investigations. Mirror movements were quantified (0-5) bidirectionally. EMG mirror movements were quantified during voluntary contraction. Motor function was quantified by validated measures including the Assisting Hand Assessment (AHA). Corticospinal organization was categorized as ipsilateral or contralateral using transcranial magnetic stimulation (TMS). The relationships between mirror movements, function, and corticospinal organization were assessed (t-tests, Pearson rank correlation coefficients). Results Ninety-two participants were scored (55 males, 37 females, mean [SD] 12y [5y 6mo], range 4-17y), 63 with complete motor outcomes and 39 with TMS data. EMG ratios correlated with clinical mirror movements (r=0.562, p=0.008). Mild mirror activity in controls declined with age (r=-0.459, p Interpretation Clinical mirror movements correlate with disability and corticospinal organization in children with unilateral CP with Perinatal Stroke. This simple bedside biomarker could facilitate patient selection for personalized rehabilitation. What this paper adds Mirror movements are a clinical indicator of corticospinal organization in children with unilateral cerebral palsy with Perinatal Stroke. Mirroring is strongest in children with ipsilateral corticospinal tract reorganization. The concept of a 'directionality factor' to mirror movements highlights additional, clinically relevant functional correlations.

  • intervention induced motor cortex plasticity in hemiparetic children with Perinatal Stroke
    Neurorehabilitation and Neural Repair, 2018
    Co-Authors: Hsingching Kuo, Adam Kirton, Ephrem Zewdie, Omar Damji, Patrick Ciechanski
    Abstract:

    Background. Clinical trials are suggesting efficacy of intensive therapy combined with brain stimulation to improve hand function in hemiparetic children with Perinatal Stroke. However, individual ...

  • interhemispheric motor interactions in hemiparetic children with Perinatal Stroke clinical correlates and effects of neuromodulation therapy
    Clinical Neurophysiology, 2018
    Co-Authors: Derek Eng, Omar Damji, Ephrem Zewdie, Patrick Ciechanski, Adam Kirton
    Abstract:

    Abstract Objective Brain stimulation and constraint therapy may enhance function after Perinatal Stroke but mechanisms are unknown. We characterized interhemispheric interactions (IHI) in hemiparetic children and explored their relationship to motor function and neuromodulation. Methods Forty-five hemiparetic Perinatal Stroke subjects aged 6–19 years completed a clinical trial of repetitive-transcranial magnetic stimulation (rTMS) and constraint therapy. Paired-pulse TMS measured IHI in cases and normal controls. Suprathreshold conditioning stimuli preceded contralateral test stimuli bidirectionally: Stroke to non-Stroke (SNS) and non-Stroke to Stroke (NSS). Primary outcome was the interhemispheric ratio (IHR) between conditioned and test only MEP amplitudes X100 ( Results Procedures were well tolerated. IHI occurred bidirectionally in controls. Eighteen Stroke participants had complete data. IHR were increased in Stroke participants in both directions. SNS IHR was >100 (facilitation) in 39% of measurements and correlated with better motor function. NSS IHR correlated with poorer motor function. Intervention-induced clinical change was not associated with IHR. Conclusions Interhemispheric interactions are altered and related to clinical function, but not necessarily neuromodulation, in children with Perinatal Stroke. Significance Adding interhemispheric interactions to evolving models of developmental plasticity following early injury may advance neuromodulation strategies.

Helen L. Carlson - One of the best experts on this subject based on the ideXlab platform.

  • developmental remodelling of the motor cortex in hemiparetic children with Perinatal Stroke
    Pediatric Neurology, 2020
    Co-Authors: Kayla Baker, Ephrem Zewdie, Helen L. Carlson, Adam Kirton
    Abstract:

    Abstract Background Perinatal Stroke often leads to lifelong motor impairment. Two common subtypes differ in timing, location, and mechanism of injury: periventricular venous infarcts (PVI) are fetal white matter lesions while most arterial ischemic Strokes (AIS) are cortical injuries acquired near term birth. Both alter motor system development and primary motor cortex (M1) plasticity, often with retained ipsilateral corticospinal fibers from the non-lesioned motor cortex (M1′). Methods Task-based functional magnetic resonance imaging was used to define patterns of motor cortex activity during paretic and unaffected hand movement. Peak coordinates of M1, M1′, and the supplementary motor area in the lesioned and intact hemispheres were compared to age-matched controls. Correlations between displacements and clinical motor function were explored. Results Forty-nine participants included 14 PVI (12.59 ± 3.7 years), 13 AIS (14.91 ± 3.9 years), and 22 controls (13.91 ± 3.4 years). AIS displayed the greatest M1 displacement from controls in the lesioned hemisphere while PVI locations approximated controls. Peak M1′ activations were displaced from the canonical hand knob in both PVI and AIS. Extent of M1 and M1′ displacement were correlated (r = 0.50, P = 0.025) but were not associated with motor function. Supplementary motor area activity elicited by paretic tapping was displaced in AIS compared to controls (P = 0.003). Conclusion Motor network components may be displaced in both hemispheres after Perinatal Stroke, particularly in AIS and those with ipsilateral control of the affected limb. Modest correlations with clinical function may support that more complex models of developmental plasticity are needed to inform targets for individualized neuromodulatory therapies in children with Perinatal Stroke.

  • imaging functional motor connectivity in hemiparetic children with Perinatal Stroke
    Human Brain Mapping, 2019
    Co-Authors: Adam Kirton, Helen L. Carlson, Jennifer Saunders, Filomeno Cortese, Bradley G Goodyear
    Abstract:

    Perinatal Stroke causes lifelong disability, particularly hemiparetic cerebral palsy. Arterial ischemic Strokes (AIS) are large, cortical, and subcortical injuries acquired near birth due to acute occlusion of the middle cerebral artery. Periventricular venous infarctions (PVI) are smaller, subcortical Strokes acquired prior to 34 weeks gestation involving injury to the periventricular white matter. Both Stroke types can damage motor pathways, thus, we investigated resulting alterations in functional motor networks and probed function. We measured blood oxygen level dependent (BOLD) fluctuations at rest in 38 participants [10 arterial patients (age = 14.7 ± 4.1 years), 10 venous patients (age = 13.5 ± 3.7 years), and 18 typically developing controls (TDCs) (age = 15.3 ± 5.1 years)] and explored strength and laterality of functional connectivity in the motor network. Inclusion criteria included MRI-confirmed, unilateral Perinatal Stroke, symptomatic hemiparetic cerebral palsy, and 6-19 years old at time of imaging. Seed-based functional connectivity analyses measured temporal correlations in BOLD response over the whole brain using primary motor cortices as seeds. Laterality indices based on mean z-scores in lesioned and nonlesioned hemispheres explored laterality. In AIS patients, significant differences in both strength and laterality of motor network connections were observed compared with TDCs. In PVI patients, motor networks largely resembled those of healthy controls, albeit slightly weaker and asymmetric, despite subcortical damage and hemiparesis. Functional connectivity strengths were not related to motor outcome scores for either Stroke group. This study serves as a foundation to better understand how resting-state fMRI can assess motor functional connectivity and potentially be applied to explore mechanisms of interventional therapies after Perinatal Stroke.

  • thalamic diaschisis following Perinatal Stroke is associated with clinical disability
    NeuroImage: Clinical, 2019
    Co-Authors: Brandon T Craig, Adam Kirton, Helen L. Carlson
    Abstract:

    Abstract Background Perinatal Stroke causes most hemiparetic cerebral palsy and leads to lifelong disability. Understanding developmental neuroplasticity following early Stroke is increasingly translated into novel therapies. Diaschisis refers to alterations brain structures remote from, but connected to, Stroke lesions. Ipsilesional thalamic diaschisis has been described following adult Stroke but has not been investigated in Perinatal Stroke. We hypothesized that thalamic diaschisis occurs in Perinatal Stroke and its degree would be inversely correlated with clinical motor function. Methods Population-based, controlled cohort study. Participants were children ( 6 months of age, symptomatic hemiparetic cerebral palsy, and no additional neurologic disorders. Typically developing controls had comparable age and gender proportions. T1-weighted anatomical scans were parcellated into 99 regions of interest followed by generation of regional volumes. The primary outcome was thalamic volume expressed as ipsilesional (ILTV), contralesional (CLTV) and thalamic ratio (CLTV/ILTV). Standardized clinical motor assessments were correlated with thalamic volume metrics. Results Fifty-nine participants (12.9 years old ±4.0 years, 46% female) included 20 AIS, 11 PVI, and 28 controls. ILTV was reduced in both AIS and PVI compared to controls (p  Conclusion Bilateral thalamic volume changes occur after Perinatal Stroke. Ipsilesional volume loss is not associated with clinical motor function. Contralesional volume is inversely correlated with clinical motor function, suggesting the thalamus is involved in the known developmental plasticity that occurs in the contralesional hemisphere after early unilateral injury.

  • Thalamic diaschisis following Perinatal Stroke is associated with clinical disability
    'Elsevier BV', 2019
    Co-Authors: Brandon T Craig, Helen L. Carlson, Adam Kirton
    Abstract:

    Background: Perinatal Stroke causes most hemiparetic cerebral palsy and leads to lifelong disability. Understanding developmental neuroplasticity following early Stroke is increasingly translated into novel therapies. Diaschisis refers to alterations brain structures remote from, but connected to, Stroke lesions. Ipsilesional thalamic diaschisis has been described following adult Stroke but has not been investigated in Perinatal Stroke. We hypothesized that thalamic diaschisis occurs in Perinatal Stroke and its degree would be inversely correlated with clinical motor function. Methods: Population-based, controlled cohort study. Participants were children (6 months of age, symptomatic hemiparetic cerebral palsy, and no additional neurologic disorders. Typically developing controls had comparable age and gender proportions. T1-weighted anatomical scans were parcellated into 99 regions of interest followed by generation of regional volumes. The primary outcome was thalamic volume expressed as ipsilesional (ILTV), contralesional (CLTV) and thalamic ratio (CLTV/ILTV). Standardized clinical motor assessments were correlated with thalamic volume metrics. Results: Fifty-nine participants (12.9 years old ±4.0 years, 46% female) included 20 AIS, 11 PVI, and 28 controls. ILTV was reduced in both AIS and PVI compared to controls (p 

  • sensory motor network functional connectivity in children with unilateral cerebral palsy secondary to Perinatal Stroke
    NeuroImage: Clinical, 2019
    Co-Authors: K.e. Woodward, Adam Kirton, Andrea M. Kuczynski, Helen L. Carlson, Jacquie Hodge, Jennifer Saunders
    Abstract:

    Abstract Background Perinatal Stroke is the most common cause of unilateral cerebral palsy. Mechanisms of post-Stroke developmental plasticity in children are poorly understood. To better understand the relationship between functional connectivity and disability, we used resting-state fMRI to compare sensorimotor connectivity with clinical dysfunction. Methods School-aged children with periventricular venous infarction (PVI) and unilateral cerebral palsy were compared to controls. Resting-state BOLD signal was acquired on 3 T MRI and analyzed using CONN in SPM12. Functional connectivity was computed between S1, M1, supplementary motor area (SMA), and thalamus of the left/non-lesioned and right/lesioned hemisphere. Primary outcome was connectivity expressed as a Fisher-transformed correlation coefficient. Motor function was measured using the Assisting Hand Assessment (AHA), and Melbourne Assessment (MA). Proprioceptive function was measured using a robotic position matching task (VarXY). Results Participants included 15 PVI and 21 controls. AHA and MA in Stroke patients were negatively correlated with connectivity (increased connectivity = poorer performance). Position sense was inversely correlated with connectivity (increased connectivity = improved performance) between the non-lesioned S1 and thalamus/SMA. In controls, VarXY was positively correlated with connectivity between the thalamus and bilateral sensorimotor regions. Conclusions Resting state fMRI measures of sensorimotor connectivity are associated with clinical sensorimotor function in children with unilateral cerebral palsy secondary to PVI. Greater insight into understanding reorganization of brain networks following Perinatal Stroke may facilitate personalized rehabilitation.

Aleksandra Mineyko - One of the best experts on this subject based on the ideXlab platform.

  • head circumference trajectory in children with Perinatal Stroke
    Journal of Child Neurology, 2021
    Co-Authors: Amanda Leong, Adam Kirton, Amalia Floer, Aleksandra Mineyko
    Abstract:

    Background:Perinatal Stroke is a leading cause of hemiparetic cerebral palsy and lifelong disability. Neurodevelopmental outcomes are difficult to predict and markers of long-term poor outcome cont...

  • population based birth prevalence of disease specific Perinatal Stroke
    Pediatrics, 2020
    Co-Authors: Jacquie Hodge, Mary Dunbar, Aleksandra Mineyko, Michael D Hill, Amalia Floer, Adam Kirton
    Abstract:

    BACKGROUND: Perinatal Stroke encompasses multiple disease-specific cerebrovascular syndromes that cause lifelong neurodevelopmental morbidity for millions worldwide. Acute presentations include neonatal arterial ischemic Stroke (NAIS), neonatal cerebral sinovenous thrombosis, and neonatal hemorrhagic Stroke (NHS). Delayed presentations include arterial presumed Perinatal ischemic Stroke, periventricular venous infarction, and presumed Perinatal hemorrhagic Stroke. Our objective was to define the birth prevalence of all subtypes of Perinatal Stroke by using a population-based cohort. METHODS: The Alberta Perinatal Stroke Project is a research cohort established in 2008 in southern Alberta, Canada, with prospective (2008–2017) and retrospective (1990–2008) enrollment leveraging universal health care at a single tertiary care pediatric center. The primary outcome was the estimated birth prevalence of each Perinatal Stroke syndrome, secondary outcomes were birth prevalence over time, sex ratios, and change in age at diagnosis. Analysis included Poisson regression, Wilcoxon rank test, and Fisher exact test. RESULTS: The overall estimated birth prevalence of term-born Perinatal Stroke was 1:1100. The estimated birth prevalence was 1:3000 for NAIS, 1:7900 for arterial presumed Perinatal ischemic Stroke, 1:6000 for periventricular venous infarction, 1:9100 for cerebral sinovenous thrombosis, 1:6800 for NHS, and 1:65000 for presumed Perinatal hemorrhagic Stroke. The apparent birth prevalence of NAIS and NHS increased over time. There were more males affected than females. The age at diagnosis decreased for late-presenting Stroke types. CONCLUSIONS: The estimated birth prevalence of term Perinatal Stroke is higher than previous estimates, which may be explained by population-based sampling of disease-specific states. This emphasizes the need for further studies to better understand the disease-specific pathophysiology to improve treatment and prevention strategies.

  • long term outcome after bilateral Perinatal arterial ischemic Stroke
    Pediatric Neurology, 2019
    Co-Authors: Aleksandra Mineyko, Adam Kirton
    Abstract:

    Abstract Aim We aimed to characterize the phenotype and outcome of children with bilateral, large vessel Perinatal arterial ischemic Stroke. Methods Patients with bilateral, large vessel Perinatal arterial ischemic Stroke were identified from a large, population-based cohort (Alberta Perinatal Stroke Project). Subjects were included if Stroke involving a major cerebral artery territory was documented in both cerebral hemispheres on magnetic resonance imaging. Standardized variables were extracted from charts including clinical presentations, associated potential risk factors, and outcomes. Outcome measures included the Pediatric Stroke Outcome Measure, Gross Motor Function Classification System, and epilepsy frequency score. Electroencephalographies were reviewed for sleep, epileptiform activity, and background. Results Of 174 children with Perinatal arterial ischemic Stroke, eight (5%) had bilateral large artery infarcts. Patients were followed for a mean of 9.7 years (range 1.8 to 14.6 years). One child died. All children had a total Pediatric Stroke Outcome Measure of ≥2 (median 8, range 2 to 10) and Gross Motor Function Classification System ≥ II. Seven of eight (88%) children had a history of epilepsy. Conclusions Children with bilateral, large vessel Perinatal Stroke are at high risk of severe cognitive and motor sequelae. Epilepsy may also be more common than unilateral Strokes. Cautious discussions with families regarding prognosis are recommended.

  • thrombophilia risk is not increased in children after Perinatal Stroke
    Blood, 2017
    Co-Authors: Colleen Curtis, Aleksandra Mineyko, Amalia Floer, Patricia Massicotte, Michael Leaker, Xiu Yan Jiang, Adam Kirton
    Abstract:

    Perinatal Stroke causes cerebral palsy and lifelong disability. Specific diseases are definable, but mechanisms are poorly understood. Evidence suggests possible associations between arterial Perinatal Stroke and prothrombotic disorders, but population-based, controlled, disease-specific studies are limited. Understanding thrombophilia in Perinatal Stroke informs pathogenesis models and clinical management. We conducted a population-based, prospective, case-control study to determine the association of specific Perinatal Stroke diseases with known thrombophilias. Children with idiopathic magnetic resonance imaging-classified neonatal arterial ischemic Stroke (NAIS), arterial presumed Perinatal ischemic Stroke (APPIS), or fetal periventricular venous infarction (PVI) were recruited. Standardized thrombophilia evaluations were performed after 12 months of age on Stroke cases and controls, including quantified proteins C and S, antithrombin, factors VIII/IX/XI, fibrinogen, lipoprotein(a), homocysteine, lupus anticoagulant, anticardiolipin antibodies and genotyping of factor V Leiden (FVL), factor II G20210A (FII), and methylenetetrahydrofolate reductase C677T. A total of 212 children were studied: 46 with NAIS, 34 with APPIS, 55 with PVI, and 77 controls (male, 53%; median age, 4.8 years). Of 14 parameters, no differences were observed in 12, including all common thrombophilias. Mean prothrombin time was shorter in arterial Strokes (P < .001). Rates of antiphospholipid antibodies were low, comparable to those in controls, and resolved on repeat testing. FVL and FII rates were comparable to population norms. Total number of possible abnormalities did not differ between cases and controls. Our prospective, population-based, controlled, disease-specific study suggests minimal association between Perinatal Stroke and thrombophilia. This does not exclude the possibility of disordered coagulation at the time of Stroke but suggests testing in childhood is not indicated.

  • transcranial direct current stimulation for children with Perinatal Stroke and hemiparesis
    Neurology, 2017
    Co-Authors: Adam Kirton, Helen L. Carlson, Ephrem Zewdie, Patrick Ciechanski, John Andersen, Alberto Nettelaguirre, Lisa Carsolio, Mia Herrero, Jillian Quigley, Aleksandra Mineyko
    Abstract:

    Objective: To determine whether the addition of transcranial direct current stimulation (tDCS) to intensive therapy increases motor function in children with Perinatal Stroke and hemiparetic cerebral palsy. Methods: This was a randomized, controlled, double-blind clinical trial. Participants were recruited from a population-based cohort with MRI-classified unilateral Perinatal Stroke, age of 6 to 18 years, and disabling hemiparesis. All completed a goal-directed, peer-supported, 2-week after-school motor learning camp (32 hours of therapy). Participants were randomized 1:1 to 1 mA cathodal tDCS over the contralesional primary motor cortex (M1) for the initial 20 minutes of daily therapy or sham. Primary subjective (Canadian Occupational Performance Measure [COPM]), objective (Assisting Hand Assessment [AHA]), safety, and secondary outcomes were measured at 1 week and 2 months after intervention. Analysis was by intention to treat. Results: Twenty-four participants were randomized (median age 11.8 ± 2.7 years, range 6.7–17.8). COPM performance and satisfaction scores doubled at 1 week with sustained gains at 2 months ( p p = 0.004). AHA scores demonstrated only mild increases at both time points with no tDCS effects. Procedures were safe and well tolerated with no decrease in either arm function or serious adverse events. Conclusion: tDCS trials appear feasible and safe in hemiparetic children. Lack of change in objective motor function may reflect underdosing of therapy. Marked gains in subjective function with tDCS warrant further study. ClinicalTrials.gov identifier: NCT02170285. Classification of evidence: This study provides Class II evidence that for children with Perinatal Stroke and hemiparetic cerebral palsy, the addition of tDCS to moderate-dose motor learning therapy does not significantly improve motor function as measured by the AHA.

Sean P. Dukelow - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of bilateral motor skills and visuospatial attention in children with Perinatal Stroke using a robotic object hitting task
    Journal of neuroengineering and rehabilitation, 2020
    Co-Authors: Rachel L. Hawe, Adam Kirton, Andrea M. Kuczynski, Sean P. Dukelow
    Abstract:

    While motor deficits are the hallmark of hemiparetic cerebral palsy, children may also experience impairments in visuospatial attention that interfere with participation in complex activities, including sports or driving. In this study, we used a robotic object hitting task to assess bilateral sensorimotor control and visuospatial skills in children with hemiparesis due to Perinatal arterial ischemic Stroke (AIS) or periventricular venous infarct (PVI). We hypothesized that performance would be impaired bilaterally and be related to motor behavior and clinical assessment of visuospatial attention. Forty-nine children with Perinatal Stroke and hemiparetic cerebral palsy and 155 typically developing (TD) children participated in the study. Participants performed a bilateral object hitting task using the KINARM Exoskeleton Robot, in which they used virtual paddles at their fingertips to hit balls that fell from the top of the screen with increasing speed and frequency over 2.3 min. We quantified performance across 13 parameters including number of balls hit with each hand, movement speed and area, biases between hands, and spatial biases. We determined normative ranges of performance accounting for age by fitting 95% prediction bands to the TD children. We compared parameters between TD, AIS, and PVI groups using ANCOVAs accounting for age effects. Lastly, we performed regression analysis between robotic and clinical measures. The majority of children with Perinatal Stroke hit fewer balls with their affected arm compared to their typically developing peers. We also found deficits with the ipsilesional (“unaffected”) arm. Children with AIS had greater impairments than PVI. Despite hitting fewer balls, we only identified 18% of children as impaired in hand speed or movement area. Performance on the Behavioral Inattention Test accounted for 21–32% of the variance in number of balls hit with the unaffected hand. Children with Perinatal Stroke-induced hemiparetic cerebral palsy may have complex bilateral deficits reflecting a combination of impairments in motor skill and visuospatial attention. Clinical assessments and interventions should address the interplay between motor and visuospatial skills.

  • bilateral reaching deficits after unilateral Perinatal ischemic Stroke a population based case control study
    Journal of Neuroengineering and Rehabilitation, 2018
    Co-Authors: Andrea M. Kuczynski, Adam Kirton, Sean P. Dukelow, Jennifer A. Semrau
    Abstract:

    Detailed kinematics of motor impairment of the contralesional (“affected”) and ipsilesional (“unaffected”) limbs in children with hemiparetic cerebral palsy are not well understood. We aimed to 1) quantify the kinematics of reaching in both arms of hemiparetic children with Perinatal Stroke using a robotic exoskeleton, and 2) assess the correlation of kinematic reaching parameters with clinical motor assessments. This prospective, case-control study involved the Alberta Perinatal Stroke Project, a population-based research cohort, and the Foothills Medical Center Stroke Robotics Laboratory in Calgary, Alberta over a four year period. Prospective cases were collected through the Calgary Stroke Program and included term-born children with magnetic resonance imaging confirmed Perinatal ischemic Stroke and upper extremity deficits. Control participants were recruited from the community. Participants completed a visually guided reaching task in the KINARM robot with each arm separately, with 10 parameters quantifying motor function. Kinematic measures were compared to clinical assessments and Stroke type. Fifty children with Perinatal ischemic Stroke (28 arterial, mean age: 12.5 ± 3.9 years; 22 venous, mean age: 11.5 ± 3.8 years) and upper extremity deficits were compared to healthy controls (n = 147, mean age: 12.7 ± 3.9 years). Perinatal Stroke groups demonstrated contralesional motor impairments compared to controls when reaching out (arterial = 10/10, venous = 8/10), and back (arterial = 10/10, venous = 6/10) with largest errors in reaction time, initial direction error, movement length and time. Ipsilesional impairments were also found when reaching out (arterial = 7/10, venous = 1/10) and back (arterial = 6/10). The arterial group performed worse than venous on both contralesional and ipsilesional parameters. Contralesional reaching parameters showed modest correlations with clinical measures in the arterial group. Robotic assessment of reaching behavior can quantify complex, upper limb dysfunction in children with Perinatal ischemic Stroke. The ipsilesional, “unaffected” limb is often abnormal and may be a target for therapeutic interventions in Stroke-induced hemiparetic cerebral palsy.

  • kinesthetic deficits after Perinatal Stroke robotic measurement in hemiparetic children
    Journal of Neuroengineering and Rehabilitation, 2017
    Co-Authors: Adam Kirton, Andrea M. Kuczynski, Sean P. Dukelow, Jennifer A. Semrau
    Abstract:

    While sensory dysfunction is common in children with hemiparetic cerebral palsy (CP) secondary to Perinatal Stroke, it is an understudied contributor to disability with limited objective measurement tools. Robotic technology offers the potential to objectively measure complex sensorimotor function but has been understudied in Perinatal Stroke. The present study aimed to quantify kinesthetic deficits in hemiparetic children with Perinatal Stroke and determine their association with clinical function. Case–control study. Participants were 6–19 years of age. Stroke participants had MRI confirmed unilateral Perinatal arterial ischemic Stroke or periventricular venous infarction, and symptomatic hemiparetic cerebral palsy. Participants completed a robotic assessment of upper extremity kinesthesia using a robotic exoskeleton (KINARM). Four kinesthetic parameters (response latency, initial direction error, peak speed ratio, and path length ratio) and their variabilities were measured with and without vision. Robotic outcomes were compared across Stroke groups and controls and to clinical measures of sensorimotor function. Forty-three Stroke participants (23 arterial, 20 venous, median age 12 years, 42% female) were compared to 106 healthy controls. Stroke cases displayed significantly impaired kinesthesia that remained when vision was restored. Kinesthesia was more impaired in arterial versus venous lesions and correlated with clinical measures. Robotic assessment of kinesthesia is feasible in children with Perinatal Stroke. Kinesthetic impairment is common and associated with Stroke type. Failure to correct with vision suggests sensory network dysfunction.

  • Sensory tractography and robot-quantified proprioception in hemiparetic children with Perinatal Stroke.
    Human brain mapping, 2017
    Co-Authors: Andrea M. Kuczynski, Sean P. Dukelow, Helen L. Carlson, Catherine Lebel, Jacquie Hodge, Jennifer A. Semrau, Adam Kirton
    Abstract:

    Perinatal Stroke causes most hemiparetic cerebral palsy, resulting in lifelong disability. We have demonstrated the ability of robots to quantify sensory dysfunction in hemiparetic children but the relationship between such deficits and sensory tract structural connectivity has not been explored. It was aimed to characterize the relationship between the dorsal column medial lemniscus (DCML) pathway connectivity and proprioceptive dysfunction in children with Perinatal Stroke. Twenty-nine participants (6-19 years old) with MRI-classified, unilateral Perinatal ischemic Stroke (14 arterial, 15 venous), and upper extremity deficits were recruited from a population-based cohort and compared with 21 healthy controls. Diffusion tensor imaging (DTI) defined DCML tracts and five diffusion properties were quantified: fractional anisotropy (FA), mean, radial, and axial diffusivities (MD, RD, AD), and fiber count. A robotic exoskeleton (KINARM) tested upper limb proprioception in an augmented reality environment. Correlations between robotic measures and sensory tract diffusion parameters were evaluated. Lesioned hemisphere sensory tracts demonstrated lower FA and higher MD, RD, and AD compared with the non-dominant hemisphere of controls. Dominant (contralesional) hemisphere tracts were not different from controls. Both arterial and venous Stroke groups demonstrated impairments in proprioception that correlated with lesioned hemisphere DCML tract diffusion properties. Sensory tract connectivity is altered in the lesioned hemisphere of hemiparetic children with Perinatal Stroke. A correlation between lesioned DCML tract diffusion properties and robotic proprioceptive measures suggests clinical relevance and a possible target for therapeutic intervention. Hum Brain Mapp 38:2424-2440, 2017. © 2017 Wiley Periodicals, Inc.

  • Robotic Quantification of Position Sense in Children With Perinatal Stroke.
    Neurorehabilitation and neural repair, 2016
    Co-Authors: Andrea M. Kuczynski, Sean P. Dukelow, Jennifer A. Semrau, Adam Kirton
    Abstract:

    Background Perinatal Stroke is the leading cause of hemiparetic cerebral palsy. Motor deficits and their treatment are commonly emphasized in the literature. Sensory dysfunction may be an important contributor to disability, but it is difficult to measure accurately clinically. Objective Use robotics to quantify position sense deficits in hemiparetic children with Perinatal Stroke and determine their association with common clinical measures. Methods Case-control study. Participants were children aged 6 to 19 years with magnetic resonance imaging-confirmed unilateral Perinatal arterial ischemic Stroke or periventricular venous infarction and symptomatic hemiparetic cerebral palsy. Participants completed a position matching task using an exoskeleton robotic device (KINARM). Position matching variability, shift, and expansion/contraction area were measured with and without vision. Robotic outcomes were compared across Stroke groups and controls and to clinical measures of disability (Assisting Hand Assessment) and sensory function. Results Forty Stroke participants (22 arterial, 18 venous, median age 12 years, 43% female) were compared with 60 healthy controls. Position sense variability was impaired in arterial (6.01 ± 1.8 cm) and venous (5.42 ± 1.8 cm) Stroke compared to controls (3.54 ± 0.9 cm, P < .001) with vision occluded. Impairment remained when vision was restored. Robotic measures correlated with functional disability. Sensitivity and specificity of clinical sensory tests were modest. Conclusions Robotic assessment of position sense is feasible in children with Perinatal Stroke. Impairment is common and worse in arterial lesions. Limited correction with vision suggests cortical sensory network dysfunction. Disordered position sense may represent a therapeutic target in hemiparetic cerebral palsy.