bluuebunny/crossref_metadata_2025 huggingface dataset:
Infraslow Status Epilepticus: A new form of subclinical status epilepticus recorded in a child with Sturge Weber Syndrome
Authors: Bello-Espinosa LE
Published: June 2015

Background: Analysis of infraslow EEG activity (ISA) has shown potential in the evaluation of patients with epilepsy and in differentiating between focal and generalized epilepsies. The purpose of this report is to present a girl with Sturge-Weber Syndrome (SWS) who was identified to have infraslow status epilepticus (ISSE), which successfully resolved after Midazolam administration Methods: The continuous EEG recording of a 5-yr-old girl with known Structural Epilepsy due to Sturge-Weber is presented. The patient presented to the ED with acute confusion, eye deviation and right hemiparesis similar to two previous admissions. ltm-eeg showed diffuse slowing. DWI obtained within 72-hr showed no ischemic changes, analysis of the EEG nfraslow (ISA) activity was undertaken using LFF 0.01 AND HFF of 0.1 Hz respectively. Results: Continuous subclinical unilateral rhythmic ictal ISA was identified. This was only evident in the left hemisphere which correlated with the structural changes due to SWS. A trial of continuous IV midazolam resulted in immediate resolution of the contralateral hemiparesis and encephalopathy. Conclusion: Continuous prolonged rhythmic ictal Infraslow activity (ISA) can cause super-refractory subclinical focal status epilepticus. This has not previously reported, and we propose this should be called Infraslow status epilepticus (ISSE). ISA analysis should be performed in all patients with unexplained subclinical status epilepticus.
Ramsay Hunt Syndrome associated with central nervous system involvement in an adult: a case report
Authors: Chan L , Cartagena A , Hosseini SM , Bombassaro A
Published: June 2015

Background: Ramsay Hunt Syndrome with cerebellar encephalitis is rare in adult. Case Report: We describe a 55-year-old diabetic female who presented with truncal ataxia, right peripheral facial palsy and right ear pain associated with erythematous vesicular lesions in her external auditory canal. Later, she developed dysmetria, fluctuating diplopia and dysarthria. No facial lesions were identified and lesions were limited to the external auditory canal. Cerebral spinal fluid tested positive for varicella zoster virus polymerase chain reaction. She was diagnosed with Ramsay Hunt Syndrome with spread to the central nervous system and treated with acyclovir intravenous therapy (10 mg/kg every 8 hours). Her facial palsy completely resolved within 48 hours of acyclovir treatment, however, vesicular lesions, imbalance and cerebellar symptoms remained; a tapering course of high dose prednisone was then added.

Discussion: Prognosis for facial palsy is poor in Ramsay Hunt Syndrome: Only 10% of patients will have complete resolution of their facial palsy. Improvement of facial palsy may be a good marker for response to treatment. Conclusion: Varicella zoster virus reactivation affecting the central nervous system in adults is rare. Knowledge of Ramsay Hunt syndrome with brainstem and/or cerebellar involvement is important for diagnosis and for consideration of antiviral and prednisone treatment.
Neurology (Movement)
Authors: Rana A , Qureshi AM , Rahman L , Rana MA , Abdullah I , Qureshi D
Published: June 2015

The objectives of the study were to analyze the association between Parkinson’s disease and restless legs syndrome, and explore the relationship between mood disorder comorbidity (anxiety and depression), pain, and restless legs syndrome. This study included 123 Parkinson’s disease patients and 123 healthy controls matched for age and gender, and evaluated for anxiety severity, depression severity, pain severity, pain interference, pain disability, and restless legs syndrome prevalence. This was performed using semi-structured interviews and a neurological examination. Restless Legs Syndrome diagnostic criteria and the following inventories were used; Hospital Anxiety and Depression Scale, Brief Pain Inventory, and Pain Disability Index. Parkinson’s disease patients had significantly greater anxiety severity, depression severity, pain severity, pain interference, pain disability, and restless legs syndrome prevalence in comparison to controls. In addition, Parkinson’s disease patients’ comorbid for anxiety and depression had significantly greater pain severity, pain interference, and pain disability, but not RLS prevalence, in comparison to Parkinson’s disease only, Parkinson’s disease anxiety, and Parkinson’s disease depression patients. Pain interference, pain severity, and pain disability is greater among Parkinson’s disease patients with anxiety and depression, in comparison to Parkinson’s disease patients without anxiety and depression. On the contrary, the prevalence of restless legs syndrome was not found to be relevant.
Vietnamese patient with progressive ataxia and palatal tremor syndrome
Authors: Jahangirvand A , Sawicka K , Kennedy S
Published: June 2015

Background: We present clinical and MRI features of progressive ataxia and palatal tremor (PAPT). Case Report: A 67 year-old gentleman visiting from Vietnam presented with intermittent stroke-like episodes consisting of facial weakness, dysarthria, and osillopsia. He reported gradually worsening ataxia and dysequilibrium over 4 years. Examination revealed small amplitude nystagmus towards the right, impaired VOR to the left, palatal tremor, left-sided dysmetria, and an unsteady gait. MRI of the brain demonstrated increased T2/FLAIR signal within the inferior olive. Contrast enhanced and diffusion sequences were normal. MRA was normal. Electrocardiography, telemetry, and echocardiogram were normal. CSF was normal. Glial fibrillary acidic protein (GFAP) and vitamin E levels were normal. Genetic testing for hereditary forms of ataxia including spinocerebellar ataxia was not completed. Conclusion: Palatal tremor is commonly classified into symptomatic or essential subgroups. Symptomatic palatal tremor is frequently caused by a lesion in the triangle of Guillain and Mollaret leading to hypertrophic olivary degeneration. A subgroup of symptomatic palatal tremor form a syndrome of PAPT. Published details of cases of PAPT are sparse and the disorder appears to be mainly sporadic. Common features include progression of ataxia, olivary degeneration, gaze-evoked nystagmus, and internuclear ophthalmoplegia. There is no known effective treatment for progressive ataxia, which is the most disabling symptom of PAPT.
The low adherence and disability outcomes of disease-modifying drugs in Multiple Sclerosis in Saskatchewan, a cohort study, 1997-2014
Authors: Hader WJ
Published: June 2015

Background: The beneficial effects of the injected disease-modifying drugs (DMDs) in relapsing-remitting Multiple Sclerosis have been previously reported. However the results related to disability outcomes and the reduction of disease progression in the pivotal trials and few longer studies are variable and inconclusive. Objectives: To determine the utilization and the disability outcomes of the DMDs on relapsing-remitting Multiple Sclerosis over fifteen years. Methods: A prospective open-label cohort of 262 clinical definite patients, 78 men and 184 women, with two attacks in the past two years and a disability level DSS≤5.5 were enrolled consecutively from December 1997 to November 1999. A descriptive analysis of the cohort and individual drugs outcomes were performed. The results were compared to natural history studies of Multiple Sclerosis as controls. Results: At 15 years, one-seventh, 38/262 (14.5%) remain on the initial prescription, Betaseron, 15/131 (11.5%), Copaxone, 16/102 (15.5%) and Rebif 7/28 (25%), Avonex 0/1. 223(63.6%) had discontinued at a mean duration of 5.5(SD=4.7) years. 95/262 (36.4%) remain on a drug after switches. The DSS levels of the individual DMDs were analyzed. Conclusion: One-seventh of participants remained on their first prescription. Because of low adherence, the impact of DMDs on disease progression in the longer term cannot be verified.
Enteral nutrition in amyotrophic lateral sclerosis (ALS): Canadian practices
Authors: Benstead T , Jackson-Tarlton C , Leddin D
Published: June 2015

Background: Dysphagia from ALS may be treated by enteral nutrition; however criteria for timing of feeding tube placement has not been well studied. The aim of this project was to better understand the practice of enteral nutrition management within Canadian ALS clinics. Methods: ALS clinics were asked if they had written guidelines for timing of PEG insertion and if not, what criteria they use to make this decision. Results: Responses from 10 of 17 clinics were received. One clinic had written guidelines. Most used decline in respiratory function, dysphagia, weight loss or some combination of all three. Six clinics reported dropping FVC, ranging from 70% to 50% as prompting tube insertion. Five clinics reported weight loss as part of their criteria. Dysphagia was reported as the most important factor by 7 clinics. Psychological readiness for tube placement was a key factor in 3 clinics. Some clinics comment they place tubes in advance of dysphagia. Conclusion: Criteria for tube insertion varies between clinics. Practices generally reflect published recommendations, but vary on the emphasis of specific criteria. The lack of strong scientific evidence to guide decisions may contribute to management variability. Further study is needed to guide practice.
Geographic distribution of Multiple Sclerosis (MS) mortality rates in Canada, 1975-2009
Authors: Warren SA , Janzen W , Warren KG , Svenson LW , Schopflocher D
Published: June 2015

Background: Our study examined whether there are differences in MS mortality rates across regions of Canada, which might suggest differences in environment or health care practice that influence outcome. Methods: Statistics Canada data on deaths due to MS and populations at risk, 1975-2009, were derived from the Research Data Centre, University of Alberta. Mortality rates and 95% confidence intervals (CIs) were calculated per 100,000 population for the Atlantic Provinces, Quebec, Ontario and Western Provinces (including Northwest Territories, Yukon, Nunavut), age-standardized to the 2006 population. Results: The average annual MS mortality rates for 1975-2009 per 100,000 population (CIs) were: Atlantic Provinces 1.09 (0.43,1.74); Quebec 1.30 (0.89,1.71); Ontario 1.08 (0.77,1.38); Western Provinces 1.39 (0.99,1.78). Female mortality rates were consistently higher than male rates but there were no differences in the female:male mortality rate ratios across regions. Trend analysis showed that rates were stable over the 35 year time span in 3 regions with non-significant average annual per cent increases/decreases of: Atlantic Provinces –0.43%; Quebec +0.12%; and Western Provinces +0.27%. Only Ontario showed a slight but significant increase of +0.81% (p<0.05). Conclusions: MS mortality rates are similar across the Canadian regions, suggesting that patients are not disadvantaged in terms of mortality by their place of residence.
Neurology (Stroke)
Authors: Liu H , Wu X , Xing Y , Liu K , Zhang H
Published: June 2015

Background: Cerebral artery stenosis is an important risk factor for ischemic strokes. This study aims to explore intracranial and extracranial artery stenosis in a large northeast Chinese cohort. Methods: We recruited 14793 outpatients and hospitalized patients to identify cerebral artery stenosis. Artery stenosis screening was done with transcranial Doppler (TCD) for intracranial arteries and carotid duplex sonography for extracranial arteries. Results: More intracranial than extracranial artery stenoses were identified (4255 versus 2809, i.e. 28.8% versus 19.0%, P<0.05). Similarly, mere intracranial stenosis was significantly more common than extracranial artery stenosis in this population (2632 versus 1186, i.e. 17.8% versus 8%, P<0.05). Among all identified intracranial arteries stenoses, the proportion of middle cerebral artery (MCA) stenosis was the highest. More intracranial than extracranial artery stenoses was seen within each age group, and rates of both increased with age. Intracranial and extracranial artery stenosis was more frequently identified in males than females. Conclusions: Incidence of cerebral artery stenosis in the population increases with age. Intracranial artery stenosis is more common than extracranial artery stenosis and the MCA stenosis accounted for the highest proportion, within each age group. More males suffer from intracranial or extracranial artery stenosis than females.
Different strokes for different folks: epidemiology of cerebrovascular diseases amongst Chinese-Canadians residing in Toronto
Authors: Chu JY , Chu JK , Chu DK , Lam S
Published: June 2015

Introduction: It has been recognized in the past few decades that different ethnic groups living in Canada may have different stroke epidemiology. This presentation is focused on the stroke patterns of Chinese-Canadians living in the Toronto area. Methods: Two retrospective case-controlled studies were carried out between 1990- 2000 to study the stroke characteristics of Chinese-Canadians living in Toronto. Statistical analysis was carried out by the Institute of Clinical Evaluative Sciences. A further retrospective study was also carried out in 2011 to look at the relationship between stroke and diabetes mellitus amongst this population. Results: Chinese-Canadians were found to have 1/6 the prevalence of extracranial vascular stenosis. They have a higher frequency of intracranial vascular disease which may be due to the higher frequency of hypertension and diabetes mellitus. Higher incidence of intracranial hemorrhage was found compared to Caucasian controls which may be due to the lack of awareness and optimal treatment of their hypertension. Details of the results of these three studies will be presented. Conclusions: This is the first long term retrospective study of the stroke patterns and epidemiology for Chinese-Canadians residing in Toronto. Further prospective population-based study will be vital to study the important interactions between genetics and environment in the pathogenesis of different strokes for different folks.
3D carotid reconstructions: imaging, pathology, algorithms and pipelines
Authors: Khan AR , Cocker M , Spence JD , Alturkustani M , Currie C , Cathie C , Hammond L , Lum C , Beanlands R , Tardif J , Hammond RR
Published: June 2015

Background: Whole-slide scanning of tissue sections spatially informed by imaging studies offers the opportunity to reconstruct specimens for co-registration to 3D imaging data. Digital image analysis algorithms can be designed to analyze and reconstruct such specimens via electronic “pipelines”. Methods: A goal of the Canadian Atherosclerosis Imaging Network (CAIN) is to improve the assessment of carotid atheromatous disease through studies that inform clinical imaging with gold-standard data (plaque pathology). To achieve this, sectioned atheromas are manually annotated and analyzed by electronic algorithm for pathological features of interest. Resulting images are then reassembled in 3D for registration to ultrasound, CT, PET-CT and MRI studies. Results: Carotid endarterectomy specimens were sub-serially sectioned, stained, digitized and annotated manually and by electronic algorithms. Resulting 2D images were successfully rendered, reassembled and analyzed in 3D using ex-vivo micro-CT as a spatial reference. Furthermore, histology quantification using colour deconvolution was found to be preferred over hue-saturation-intensity methods 94.7-100% of the time in a blinded multiple rater study. Conclusion: Automated “pipelines” greatly facilitate 3D reconstruction in comparison to traditional slice-by-slice methods. Transformations spatially guided by pre-existing imaging data is not only faster, but has superior objectivity and fidelity. With embedded annotations, 3D pathology maps become a rich, micron-level, permanent digital pathological database for correlative studies.
Subjective anxiety ratings before and after stressful neurosurgical virtual reality tumor resection task
Authors: Winkler-Schwartz A , Fares J , Khalid B , Baggiani M , Christie S , Alotaibi F , Al-Zharni G , Sabbagh A , Azarnoush H , Werthner P , Del Maestro R
Published: June 2015

Background: The availability of virtual reality (VR) surgical simulators affords the opportunity to assess the influence of stress on neurosurgical operative performance in a controlled laboratory environment. This study sought to examine the effect of a stressful VR neurosurgical task on the subjective anxiety ratings of participants with varying levels of surgical expertise. Methods: Twenty four participants comprised of six staff neurosurgeons, six senior neurosurgical residents (PGY4-6), six junior neurosurgical residents (PGY1-3), and six senior medical students took part in a bimanual VR tumor removal task with a component of sudden uncontrollable intra-operative bleeding. State Trait Anxiety Inventory (STAI) questionnaires were completed immediately pre and post the stress stimulus. The STAI questionnaire consisted of six items (calm, tense, upset, relaxed, content and worried) measured on a Likert scale. Results: Significant increases in subjective anxiety ratings were noted in junior residents (p=0.005) and medical students (p=0.025) while no significant changes were observed for staff and senior neurosurgical residents. Conclusions: Staff and senior residents more effectively mitigate stress compared to junior colleagues in a VR operative environment. Further physiological correlates are needed to determine whether this increased anxiety is paralleled by physiological arousal and altered surgical performance.
Neurosurgery (Neuro Oncology)
Authors: Mansouri A , Shin S , Cooper B , Kondziolka D
Published: June 2015

Background: Deficiencies in design and reporting of randomized controlled trials (RCTs) limit their validity. The quality of recent RCTs in neuro-oncology was analyzed to assess adequacy of design and reporting. Methods: The MEDLINE and EMBASE databases were searched to identify non-surgical RCTs (years 2000-2010). The CONSORT and Jadad scales were used to assess the quality of design/reporting. A PRECIS-based scale was used to designate studies on the pragmatic-explanatory continuum. Spearman’s test was used to assess correlations. Regression analysis was used to assess associations. Results: Overall, 44 RCTs were identified; majority (23 studies) were chemotherapy-based. High grade gliomas (43%) and metastases (41%) were top pathologies. The majority of studies were multi-center (70%), ITT (61%), and did not collaborate with biostatisticians (70%). Half of the studies were funded by industry (50%). The median CONSORT and Jadad scores were similar in radiation and chemotherapy-based trials (34 and 35 vs 3 and 2, respectively). The impact factor was significantly associated with higher quality (p<0.01). Multi-center trials were more likely to result in positive outcomes (p = 0.02). Conclusion: Deficiencies in the quality of design and reporting of RCTs in neuro-oncology persist. Quality improvement is necessary. In parallel, alternative strategies may be required.
Operative management of C3-C6 intramedullary gangliocytoma
Authors: Dalkilic T , Kindrachuk M , Tymchak Z , Fourney D
Published: June 2015

Background: Gangliocytoma is a WHO grade 1 tumour which is typically found in the brain. Incidence of this pathology occurring in the spinal cord is rare, accounting for 0.1%-0.4% of intramedullary spinal cord tumors. Methods: We present the case of a previously healthy 23-year-old male with bilateral weakness and accompanying sensory deficits progressing over several months. Magnetic resonance imaging (MRI) of the spine showed a C3-C6 enhancing, intramedullary mass. C3-6 laminoplasty and resection of the tumour was preformed under neurophysiologic monitoring. Post-operatively the patient had no new neurologic deficits. Results: Final histopathology was consistent for gangliocytoma with extensive calcifications as confirmed by two separate neuropathologists. Gross total resection was not possible due to decreased motor evoked potentials detected by electrophysiologic monitoring. Post-operative MRI revealed a residual tumour measuring 58×15×25 mm with no further abnormal foci of enhancement. Conclusions: Gangliocytoma of the cervical cord is exceedingly rare, however its natural history is unclear. In our experience, maximal safe resection is warranted with the goal of preserving neurological status.
Neurosurgery (Spine)
Authors: Shamji MF , Mohanty C , Massicotte EM , Fehlings MG
Published: June 2015

Objective: The impact of spinal alignment on neurological recovery among myelopathy patients has not been thoroughly investigated. This study evaluated the impact of sagittal cervical alignment on neurological recovery in a prospective surgical series of myelopathy patients. Methods: Prospective data was analyzed from surgical CSM patients at a tertiary-care neurosurgical centre. Demographic data and clinical preoperative and postoperative measures of neurological disability (mJOA, Nurick, NDI scores) were analyzed for dependency on cervical spine imaging parameters. Results: Among 124 CSM patients, 34% exhibited kyphotic alignment. Surgical intervention was more frequently anterior or combined anterior/posterior among this group than those with preserved lordosis. Most patients exhibited postoperative neurological improvement for myelopathy severity, however the extent of this improvement was dichotomous based on preoperative sagittal alignment. Improvement was greater among patients with preoperative lordosis (ΔmJOA of 3.1) than those with preoperative kyphosis (ΔmJOA of 1.4, p=0.02). Surgical correction of spinal malalignment did not provide for heightened neurological recovery, although whether it protects against symptomatic adjacent segment disease is unclear. Conclusion: Most CSM patients showed postoperative neurological improvement. Patients with preoperative lordotic alignment exhibited greater improvement than those with preoperative kyphotic alignment. Neither correction of the spinal alignment nor surgical approach in this series specifically affected the extent of neurological recovery.
Obesity and lumbar fusion: increased risk of blood loss
Authors: Jewett GA , Yavin D , Sahota IS , Dhaliwal P , Du Plessis S
Published: June 2015

Background: Several studies have demonstrated that obese patients are at increased risk of perioperative complication during lumbar spine surgery. Herein we quantify the association between blood loss and obesity during lumbar fusion. Methods: Outcomes were collected in the setting of a single center randomized control trial conducted among patients undergoing elective lumbar fusion. A univariate analysis of potential risk factors (gender, age, body mass index [BMI], number of levels fused, previous use of anticoagulants, and previous use of non-steroidal anti-inflammatories) for operative blood loss was performed. Logistic regression was conducted to estimate adjusted odds ratios (ORs) and 95% confidence intervals. Results: Among 85 patients, the mean estimated blood loss (EBL) was 563 ml, 47.1% were male, and the median number of levels fused was one. Obesity (BMI ≥30−kg/m2) was a significant risk (OR 2.46, P=0.025) for increased blood loss (EBL > 500 ml). Number of levels fused was similarly associated with EBL (P<0.01) while gender confounded the association between obesity and EBL. Conclusions: Surgeons should anticipate greater blood loss when performing lumbar fusion in obese patients. To reduce operative morbidity, consideration should be given to preoperative weight loss whenever possible.
Os Odontoideum: an unusual association of compressive synovial cyst. Case report and review of the literature
Authors: Ahmed AA , Watson T , Elgheriani A , Kachur E , Cenic A
Published: June 2015

Background: Os odontoideum is a rare cervical abnormality that harbours a potential risk for atlantoaxial instability. In rare circumstances, synovial cysts may develop and compromise the spinal cord. Therefore, cyst excision has been suggested as part of the surgical management. However, in recent reports, it has been shown that atlantoaxial stabilization alone is sufficient for synovial cyst regression. Methodology: 48-year-old woman presented with symptoms and signs of cervical myelopathy secondary to os odontoideum with atlantoaxial instability. A large synovial cyst was diagnosed with significant spinal cord compression. In addition, her spinal and cranial imaging was suggestive of multiple sclerosis which was confirmed clinically thereafter with one episode of MS flare up and positive cerebrospinal fluid analysis. Results: After she had recovered from her MS flare up, posterior atlantoaxial instrumentation and fusion was performed without synovial cyst resection. Postoperatively, her clinical condition improved substantially and complete regression of the synovial cyst was noted on cervical MRI. Interestingly, she has not had any MS recurrent episodes after the surgery. Conclusion: Degenerative changes in os odontoideum are consequences of atlantoaxial instability. Compressive synovial cysts may develop with associated cord compression. We recommend posterior atlantoaxial stabilization alone in such conditions while preserving cyst fenestration or excision for persistent symptoms related to unresolved synovial cysts.
Increased focal and diffuse cerebral demand after concussion
Authors: Sojoudi A , MacMaster F , Barlow KM , Khetani A
Published: June 2015

Aim: To examine cortical activation during a memory task in children with and without post-concussion symptoms (PCS) following concussion. Methods: A case-controlled study within the PlayGame Trial (www.playgametrial.ca). Children (aged 8-18 years) with PCS at 1-month post-injury were eligible. The fMRI task was a working memory task. Pre-processing and single-subject analysis were performed in FSL. Group activation and inter-group difference maps were extracted. Results: 11 symptomatic, 12 asymptomatic, and 11 controls without concussion participated. Groups were similar in age (14.9, 14.0, and 13.8yrs; p=0.46), sex (p=0.984) and time post-injury (symptomatic: 37d; asymptomatic 35d; p=0.573). Compared with controls, symptomatic children demonstrated greater activation especially in the bilateral orbito-frontal cortex and cerebellum. A similar, less pronounced pattern was observed in asymptomatic subjects. Conclusions: Similar to adult studies, increased network activation may represent decreased “efficiency” and explain the cognitive fatigue in PCS. Further, children who are “asymptomatic” may not yet be fully recovered.
Understanding the evolution of epilepsy – the value of collecting longitudinal data in the setting of a first seizure clinic
Authors: Pohlmann-Eden B , Legg KT , Schmidt MH , Crocker CE
Published: June 2015

Objective: Our knowledge of disease mechanisms in epilepsy is biased by findings originating from cross-sectional studies and advanced stages of epilepsy. We provide a new perspective by collecting systematically longitudinal data from patients who present in early stages (ES). Methods: The Halifax First Seizure Clinic, founded in 2008, uses a comprehensive multimodal data basis addressing clinical presentation, neuroimaging, EEG findings, genetics, cognition, comorbidities, social parameters, and life style. Follow-up visits are 6, 12 and 24 months. Results: Out of 575 patients we identified 3 subgroups 1) Strictly first seizure, n=187, 2) New-onset epilepsy (> 1 seizure < 12 months), n=149, and 3) Newly-diagnosed epilepsy (seizures > > 12 months), n=50. 189 patients were excluded (not proven seizure or other conditions e.g syncope etc.). Our interim analyses suggest: A) pharmacoresistance presents in highly diverse patterns and is rarer than expected in ES, B) Congenital malformations seem to have an excellent treatment prognosis in ES, C) Marijuana consumption is significantly more prevalent at initial assessment (comparison general population), D) Preceding psychiatric comorbidities associated with reduced amygdalar volume may be a predictor for seizure recurrence. Conclusions: The preliminary and illustrative findings of our pilot study challenge current concepts of disease evolution in epilepsy.
A novel fusiform aneurysmal model in a rabbit carotid: a combination of pericarotid calcium chloride and elastase incubation
Authors: Alaqeel A , Meek C , Wong J , Mitha A
Published: June 2015

Background: The purpose of this study was to develop a novel, simple and effective model of fusiform artery aneurysms in rabbits using a combination of periaortic calcium chloride (CaCl2) and elastase incubation. Methods: Fusiform aneurysms were developed in three New Zealand White rabbits by exposing a 2 cm segment of the right carotid artery to CaCl2 (0.5 mol/L) and pancreatic porcine elastase (75 U) for 20 minutes. The left carotid was used as a control. Vessel diameter was measured by serial digital subtraction angiography imaging at weeks 2, 4 and 6. Animals were sacrificed on week 6 and histopathological studies were performed. Results: All rabbits developed a fusiform aneurysm, with an average dilation ratio of 105%±10% by week 6. No mortality was reported. Histopathological studies revealed pathological features consistent with fusiform aneurysms. Conclusions: This novel rabbit model of fusiform carotid aneurysms is the first in the literature by using a combination of periaortic CaCl2 and elastase incubation. This is a simple, reliable, and effective technique and results in a potentially valuable model for the study of fusiform aneurysms and possible therapeutic interventions, such as flow diversion.
CACN Platform Presentations
Authors: Yang MM , Singhal A , Kerr JM , Hengel AR , George S , Thiessen P , Muir K , Enarson P
Published: June 2015

Background: Fundoscopy is an important component of the neurological examination, but can be challenging in uncooperative children. This study explores whether playing a video during eye examination, improves the success, duration and ease of pediatric fundoscopy. Methods: We completed a prospective, multi-clinic, block-randomized trial. Patients 1-4 years were recruited in the emergency department, neurology, spinal cord and general pediatric clinic. Patients were randomized (by eye examined) to video/non-video assisted fundoscopy. Successful exams were defined as visualizing the fundus within 60 seconds. Time to visualize optic disc was recorded and difficulty of exam was examined using a 10-point Likert scale. Results: 101 subjects were recruited, with a mean age of 2.8 years. Overall, there was a 20% absolute improvement in the success rate of visualizing the optic disc in the video versus non-video group (p<0.01). Time to visualize optic disc was also improved (Δ5.3s, p<0.01). Improvement in ease of examination with video were noted by caregivers and practitioners (p<0.01). Conclusion: Playing a video improved the ease, duration and most importantly the success of fundoscopy in younger children. This simple, inexpensive adjunct has great potential to improve the ease and efficacy of this aspect of the neurological examination.
Canadian Paediatric Neurology Workforce survey and consensus statement
Authors: Doja A , Orr S , McMillan H , Kirton A , Callen D
Published: June 2015

Background: Little knowledge exists on the availability of paediatric neurology positions. Our study aimed to: 1) obtain information regarding the availability of positions for paediatric neurologists in academic centres; 2) survey paediatric neurology trainees regarding their perceptions of employment issues and career plans; 3) survey practicing community paediatric neurologists 4) convene a group of paediatric neurologists to develop a consensus regarding how to address these workforce issues. Methods: Surveys addressing workforce issues regarding paediatric neurology in Canada were sent to: 1) all paediatric neurology program directors in Canada who then solicited information from division heads and from paediatric neurologists in surrounding areas; 2) paediatric neurology trainees in Canada and; 3) community paediatric neurologists. A meeting was held with relevant stakeholders to develop a consensus on how to approach employment issues. Results: We found that the number of projected positions in academic paediatric neurology is fewer than the number of paediatric neurologists that are being trained. Paediatric neurology residents are concerned about job availability and desire more career counselling. Conclusions: There is a current and projected clinical demand for paediatric neurologists despite a lack of academic positions. Training programs should focus on community neurology as a viable career option.
The diverse manifestations of tuberous sclerosis complex: the experience of a provincial TSC clinic
Authors: Wilbur C , Sanguansermsri C , Chable H , Mihaela A , Connolly MB
Published: June 2015

Background: Recent consensus recommendations for Tuberous Sclerosis Complex (TSC) stress the importance of multidisciplinary follow-up for these patients. The objective of our study was to review the manifestations of TSC seen in our hospital to determine the care needs of this population. Methods: This was a systematic, retrospective chart review of children with TSC treated at our institution. Patients were identified through epilepsy and clinical neurophysiology databases. Results: The study population comprised 81 patients, born between 1987-2014, who were a median 10 (Range 0.2-23.2) years of age at last follow-up. 88% of patients had epilepsy, including 30% with a history of infantile spasms. Developmental delay was reported in 65%, while 40% had intellectual disability. Psychiatric co-morbidities occurred in 49%. The most common psychiatric diagnoses were autism (25%), ADHD (19%), and anxiety (16%). Cardiac rhabdomyomas occurred in 35% of patients and renal angiomyolipomas in 42%, while only 4% had polycystic kidneys. Subependymal giant cell astrocytomas were observed in 14% of patients. 86% had skin manifestations. Conclusions: This study reaffirms the multi-system manifestations of TSC and the need to provide comprehensive, multidisciplinary care. As many children are still very young, the prevalence of autism and intellectual disability is likely underestimated.
Local flow topology and velocity gradient invariants in compressible turbulent mixing layer
Authors: Vaghefi Navid S. , Madnia Cyrus K.
Published: June 2015

The local flow topology is studied using the invariants of the velocity gradient tensor in compressible turbulent mixing layer via direct numerical simulation (DNS) data. The topological and dissipating behaviours of the flow are analysed in two different regions: in proximity of the turbulent/non-turbulent interface (TNTI), and inside the turbulent region. It is found that the distribution of various flow topologies in regions close to the TNTI differs from inside the turbulent region, and in these regions the most probable topologies are non-focal. In order to better understand the behaviour of different flow topologies, the probability distributions of vorticity norm, dissipation and rate of stretching are analysed in incompressible, compressed and expanded regions. It is found that the structures undergoing compression–expansion in axial–radial directions have the highest contraction rate in locally compressed regions, and in locally expanded regions the structures undergoing expansion–compression in axial–radial directions have the highest stretching rate. The occurrence probability of different flow topologies conditioned by the dilatation level is presented and it is shown that the structures in the locally compressed regions tend to have stable topologies while in locally expanded regions the unstable topologies are prevalent.
Budgets of turbulent kinetic energy, Reynolds stresses, variance of temperature fluctuations and turbulent heat fluxes in a round jet
Authors: Darisse Alexis , Lemay Jean , Benaïssa Azemi
Published: June 2015

The self-preserving region of a free round turbulent air jet at high Reynolds number is investigated experimentally (at$x/D=30$,$\mathit{Re}_{D}=1.4\times 10^{5}$and$\mathit{Re}_{{\it\lambda}}=548$). Air is slightly heated ($20\,^{\circ }\text{C}$above ambient) in order to use temperature as a passive scalar. Laser doppler velocimetry and simultaneous laser doppler velocimetry–cold-wire thermometry measurements are used to evaluate turbulent kinetic energy and temperature variance budgets in identical flow conditions. Special attention is paid to the control of initial conditions and the statistical convergence of the data acquired. Measurements of the variance, third-order moments and mixed correlations of velocity and temperature are provided (including$\overline{vw^{2}}$,$\overline{u{\it\theta}^{2}}$,$\overline{v{\it\theta}^{2}}$,$\overline{u^{2}{\it\theta}}$,$\overline{v^{2}{\it\theta}}$and$\overline{uv{\it\theta}}$). The agreement of the present results with the analytical expressions given by the continuity, mean momentum and mean enthalpy equations supports their consistency. The turbulent kinetic energy transport budget is established using Lumley’s model for the pressure diffusion term. Dissipation is inferred as the closing balance. The transport budgets of the$\overline{u_{i}u_{j}}$components are also determined, which enables analysis of the turbulent kinetic energy redistribution mechanisms. The impact of the surrogacy$\overline{vw^{2}}=\overline{v^{3}}$is then analysed in detail. In addition, the present data offer an opportunity to evaluate every single term of the passive scalar transport budget, except for the dissipation, which is also inferred as the closing balance. Hence, estimates of the dissipation rates of turbulent kinetic energy and temperature fluctuations (${\it\epsilon}_{k}$and${\it\epsilon}_{{\it\theta}}$) are proposed here for use in future studies of the passive scalar in a turbulent round jet. Finally, the budgets of turbulent heat fluxes ($\overline{u_{i}{\it\theta}}$) are presented.
The relationship between the board of directors and firm performance in private family firms: A test of the demographic versus behavioral approach
Authors: Basco Rodrigo , Voordeckers Wim
Published: June 2015

Research on corporate governance has attempted to investigate the added value of boards of directors through the lenses of both demographic and behavioral approaches. However, investigations into these two approaches, and the subsequent implications for firm performance, have thus far been mainly decoupled from one another. Therefore, the aim of this paper is to put both approaches to the test in the family business context. Using a sample of 567 Spanish family firms, we find that although both approaches can explain the performance of family firms, the behavioral approach explains a much higher proportion of the variation in the firm’s performance. Furthermore, our findings support our hypotheses that the relationship between the proportion of outside directors and firm performance follows an inverted U-shape in private family firms, and that both business-oriented and family-oriented board role performance are positively related with firm performance.
Using experimental decay of modern forms to reconstruct the early evolution and morphology of fossil enteropneusts
Authors: Nanglu Karma , Caron Jean-Bernard , Cameron Christopher B.
Published: June 2015

Decay experiments are becoming a more widespread tool in evaluating the fidelity of the fossil record. Character interpretations of fossil specimens stand to benefit from an understanding of how decay can result in changes in morphology and, potentially, total character loss. We performed a decay experiment for the Class Enteropneusta to test the validity of anatomical interpretations of the Burgess Shale enteropneust Spartobranchus tenuis and to determine how the preservation of morphological features compares with the sequence of character decay in extant analogues. We used three species of enteropneust (Saccoglossus pusillus, Harrimania planktophilus, and Balanoglossus occidentalis) representing the two major families of Enteropneusta. Comparisons between decay sequences suggest that morphological characters decay in a consistent and predictable manner within Enteropneusta, and do not support the hypothesis of stemward slippage. The gill bars and nuchal skeleton were the most decay resistant, whereas the gill pores and pre-oral ciliary organ were unequivocally the most decay prone. Decay patterns support the identification of the nuchal skeleton, gill bars, esophageal organ, trunk, and proboscis in Spartobranchus tenuis and corroborate a harrimaniid affinity. Bias due to the taphonomic loss of taxonomically informative characters is unlikely. The morphologically simple harrimaniid body plan can be seen, therefore, to be plesiomorphic within the enteropneusts. Discrepancies between the sequence of decay in a laboratory setting and fossil preservation also exist. These discrepancies are highlighted not to discredit the use of modern decay studies but rather to underline their non-actualistic nature. Paleoenvironmental variables besides decay, such as the timeframe between death and early diagenesis as well as postmortem transport, are discussed relative to decay data. These experiments reinforce the strength of a comprehensive understanding of decay sequences as a benchmark against which to describe fossil taxa and understand the conditions leading to fossilization.
Diagenesis of bivalves from Jurassic and Lower Cretaceous lacustrine deposits of northeastern China
Authors: FÜRSICH FRANZ T. , PAN YANHONG
Published: June 2015

In contrast to the numerous excellently preserved arthropods, vertebrates and plants from the Mesozoic lacustrine fossil lagerstätten of northeastern China, which have calcium phosphate or organic skeletons, the preservation of taxa with a calcareous skeleton is fairly poor. Here we investigate, using a scanning electron microscope and energy dispersive X-ray spectrometer, the preservational modes of bivalves from the Jurassic Daohugou Fossil Beds of Inner Mongolia and the Lower Cretaceous Yixian Formation of eastern Liaoning. The Jurassic bivalve Ferganoconcha sibirica is preserved as strongly compressed composite moulds which contain remains of the organic periostracum. In the Yixian Formation, the bivalves Sphaerium anderssoni and Arguniella ventricosa occur as compacted internal, external or composite moulds or are preserved with a silicified shell, and rarely with a shell consisting of iron hydroxides, which had replaced pyrite during late diagenesis/weathering. Silicification produced partly fabric-replacive microcrystalline quartz and partly void-filling megaquartz crystals after the carbonate shell had been dissolved. Films of authigenic aluminosilicate minerals, partly secondarily silicified, cover the exterior and interior shell surfaces. Occasionally, early diagenetic pyrite crystals, now oxidized to iron hydroxides, filled shell cavities forming internal moulds and rarely replaced the bivalve shell. The poor preservation of the bivalves reflects the environment and water chemistry of these lakes, which were heavily influenced by volcanic processes. Frequent ash deposition and decomposition of volcanic glass particles created acidic and alkaline lake and interstitial waters, which led to early diagenetic formation of authigenic aluminosilicate minerals, ferruginous internal moulds, dissolution of shell carbonate and silicification of shells.
Large predatory marine reptiles from the Albian–Cenomanian of Annopol, Poland
Authors: BARDET NATHALIE , FISCHER VALENTIN , MACHALSKI MARCIN
Published: June 2015

During the Early–Late Cretaceous transition, marine ecosystems in Eurasia hosted a diverse set of large predatory reptiles that occupied various niches. However, most of our current knowledge of these animals is restricted to a small number of bonebed-like deposits. Little is known of the geographical and temporal extent of such associations. The middle Albian – middle Cenomanian phosphorite-bearing succession exposed at Annopol, Poland produces numerous ichthyosaurian and plesiosaurian fossils. These are mostly isolated skeletal elements (e.g. teeth, vertebrae), but disarticulated partial skeletons and an articulated, subvertically embedded ichthyosaur skull are also available. The following taxa are identified: ‘Platypterygius’ sp., cf. Ophthalmosaurinae, Ichthyosauria indet.,Polyptychodon interruptus, Pliosauridae indet., Elasmosauridae indet. and Plesiosauria indet. The large-sized ichthyosaur ‘Platypterygius’ and the pliosauridPolyptychodon interruptuspredominate within the upper Albian – middle Cenomanian deposits. The Annopol record, combined with data from England, France and western Russia, suggests that ‘Platypterygius’ andPolyptychodon interruptusformed a long-term, stable ecological sympatry in marine ecosystems of the European archipelago, at least during the Albian – middle Cenomanian. In addition, the marine reptile assemblage from Annopol is distinct from other Eurasian ecosystems in containing also elasmosaurids in its Albian portion.
ETHNICITY AND INCOME IMPACT ON BMI AND STATURE OF SCHOOL CHILDREN LIVING IN URBAN SOUTHERN MEXICO
Authors: Mendez Nina , Barrera-Pérez The Late Mario , Palma-Solis Marco , Zavala-Castro Jorge , Dickinson Federico , Azcorra Hugo , Prelip Michael
Published: June 2015

Obesity affects quality of life and increases the risk of morbidity and mortality. Mexico, a middle-income country, has a high prevalence of overweight and obesity among urban children. Merida is the most populated and growing city in southern Mexico with a mixed Mayan and non-Maya population. Local urbanization and access to industrialized foods have impacted the eating habits and physical activity of children, increasing the risk of overweight and obesity. This study aimed to contribute to the existing literature on the global prevalence of overweight and obesity and examined the association of parental income, ethnicity and nutritional status with body mass index (BMI) and height in primary school children in Merida. The heights and weights of 3243 children aged 6–12 from sixteen randomly selected schools in the city were collected between April and December 2012. Multinomial logistic regression models were used to examine differences in the prevalence of BMI and height categories (based on WHO reference values) by ethnicity and income levels. Of the total students, 1648 (50.9%) were overweight or obese. Stunting was found in 227 children (7%), while 755 (23.3%) were defined as having short stature. Combined stunting and overweight/obesity was found in 301 students (9.3%) and twelve (0.4%) were classified as stunted and of low weight. Having two Mayan surnames was inversely associated with having adequate height (OR=0.69, p<0.05) and the presence of two Maya surnames in children increased the odds of short stature and stunting. Children from lower income families had twice the odds of being stunted and obese. Overweight, obesity and short stature were frequent among the studied children. A significant proportion of Meridan children could face an increased risk of developing cardiovascular disease and its associated negative economic and social outcomes unless healthier habits are adopted. Action is needed to reduce the prevalence of obesity among southern Mexican families of all ethnic groups, particularly those of lower income.
A Rejoinder to Tirthankar Roy
Authors: GHOSH SHAMI
Published: June 2015

I am grateful to Tirthankar Roy for his prompt response, and his generosity in acknowledging the validity of some of my criticisms. It will be obvious to readers that there are some fundamental disagreements between us regarding what constitutes economic history. On this, and a number of other issues that Professor Roy has chosen not to address, it would be tedious to repeat myself; we must agree to disagree and invite readers of this journal to draw for themselves the conclusions they wish—and, ultimately, how fair I have been in assessing his book is something that readers will only be able to judge by reading it themselves. I focus below on the three core issues with which most of his response is concerned: ‘reading the past with reference to the present’, the importance of a ‘region-focused approach’, and the ‘comparative approach’.