Background: Antithrombosis (AT), with antiplatelets or anticoagulants, is a significant risk factor for the development of chronic subdural hematomas (cSDH). Resumption of AT following hematoma evacuation is variable, with scant evidence for guidance. Methods: We retrospectively analyzed 479 patients with surgically-evacuated cSDH at St. Michael’s Hospital from 2007-2012. Collected variables included type of AT, indication for AT, timing and type of postoperative complications, and restart intervals for AT agents. Postoperative complications were classified as major or minor hemorrhages, or thromboembolism. Results: Among all patients, 14.8% experienced major hemorrhage, 23.0% minor hemorrhage, and 1.67% thromboembolism. Patients on any preoperative AT were at higher risk of major hemorrhage (OR=1.93, p=0.014), experienced earlier major hemorrhage (mean 16.2 versus 26.5d, p=0.052) and earlier thromboembolism (mean 2.7 versus 51.5d, p=0.036). The type of agent did not affect complication frequency or timing. Patients restarted on any AT postoperatively were at decreased risk of major rebleed following resumption, than those not restarted (OR=0.06, p<0.01). Conclusions: Patients on preoperative AT experienced thromboembolism significantly earlier, at 3d postoperatively, with no increase in rebleed risk following AT resumption. We provide cursory evidence that resuming AT early, at 3d postoperatively, may be safe. Larger prospective studies are required for definitive recommendations.

Background: Horse riding is a hazardous activity with the potential for serious injury. Equestrian-related injuries account for a higher rate of injury per number of riding hours than motorcyclists and automobile racers. There is a lack of literature pertaining to equestrian-related brain injuries. The objectives of this study were to describe the incidence, characteristics, and mechanisms of equestrian-related brain injuries sustained amongst Canadians between 1990 and 2014. Methods: Data were obtained from the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) database. The study population consisted of individuals who sustained equestrian-related brain injuries between the years 1990 and 2014 and presented to one of 15 participating emergency departments. Results: Brain injuries accounted for 13.3% (N=1060) of all equestrian-related injuries. The greatest proportion of injuries occurred amongst individuals aged 15-19 years, followed by individuals aged 0-4 years. The predominant mechanism of injury was falls. 17.9% of individuals were admitted to hospital. Normalized rates of injury increased from 1990 to 2010. Conclusions: Brain injuries sustained while participating in equestrian are often of a greater severity than injuries sustained while participating in other recreational activities. A clear understanding of the epidemiology and mechanisms of equestrian-related brain injuries must be achieved in order to effectively implement prevention efforts.

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.

Background: Deficiencies in design and reporting of randomized controlled trials (RCTs) limit their validity. The quality of recent RCTs in neurosurgery was analyzed to assess adequacy of design and reporting. Methods: A high-yield search of the MEDLINE and EMBASE databases (2000-present) was conducted. 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: Sixty-one articles were identified. Vascular was the most common sub-specialty (37%). The median CONSORT and Jadad scores were 36 (IQR 27.5-39) and 3 (IQR 2-3). Blinding, sample size calculation and allocation concealment were most deficiently reported. The quality of reporting did not correlate with the study impact. The majority of studies (83%) had pragmatic objectives; while pragmatic studies had compatible design factors, trials with explanatory objectives were less successful. Conclusions: The prevalence and quality of neurosurgical RCTs is low. Many study designs are not compatible with stated objectives. Given the role of RCTs as one of the highest levels of evidence, it is critical to improve on their methodology and reporting. Alternative methodologies merit discussion.

On February 11, 2015, the Canadian Food Inspection Agency announced that a cow born and raised in Alberta had tested positive for bovine spongiform encephalopathy (BSE), commonly known as mad cow disease. BSE is a prion disease of cattle that, when transmitted to humans, produces a fatal neurodegenerative disease known as variant Creutzfeldt-Jakob disease. We believe that this latest case of BSE in Canadian cattle suggests the timeliness of a review of the management of BSE in Canada from a historically and scientifically informed perspective. In this article, we ask: how did the Canadian management of BSE between 1990 and 2014 engage with the contemporary understanding of BSE’s human health implications? We propose that Canadian policies largely ignored the implicit medical nature of BSE, treating it as a purely agricultural and veterinary issue. In this way, policies to protect Canadians were often delayed and incomplete, in a manner disturbingly reminiscent of Britain’s failed management of BSE. Despite assurances to the contrary, it is premature to conclude that BSE (and with it the risk of variant Creutzfeldt-Jakob disease) is a thing of Canada’s past: BSE remains very much an issue in Canada’s present.

Introduction: Patients presenting with high grade (HG) subarachnoid hemorrhage (SAH) from aneurysmal rupture may have persisting neurologic deficits which may lead to questioning the decision of treating aggressively. The objective of this study aims at analyzing outcome and long-term quality of life (QOL) of patients with HG SAH treated surgically. Methods: Retrospective study of patients with Hunt Hess (HH) grade IV or V SAH treated surgically at our institution. Long-term outcome was evaluated based on the modified Rankin Scale (mRS) at 3 years. Survivors were evaluated for QOL using various scales. Results: 63 patients (mean age of 52 year-old) were included. Intraparenchymal hemorrhage (IPH) was found in 85% of cases. 19 patients died. Predictive factors of poor prognosis and mortality were initial cerebral ischemia (p=0.003) and IPH (p=0.007). Favourable outcome (mRS 0-3) was found in 41% of patients. QOL questionnaires revealed that 80 % of responders showed more than 50% recovery. Mild or absent depression was observed in 78% of patients. Conclusion: In this surgical series, performed in an endovascular era, nearly all patients presented with SAH-associated IPH at admission. Despite the presence of such negative prognostic factor and the poor condition at admission, a high rate of favourable outcome and QOL was observed, therefore justifying aggressive surgical treatment.

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.

Background & Objectives: Of patients with pyridoxine-dependent epilepsy (PDE) due to ATQ deficiency, 75% suffer intellectual disability despite adequate seizure control with high dose pyridoxine. We aimed to assess the safety and efficacy of two novel therapeutic strategies to reduce accumulation of toxic intermediates in this cerebral lysine degradation defect. Methods: In two open-label observational studies, seven children with confirmed ATQ deficiency were started on dietary lysine restriction with regular nutritional monitoring, and outcome evaluation pipecolic acid, AASA levels in body fluids; development/cognition via age-appropriate tests and parental observations; epilepsy). Subsequently additional arginine supplementation was initiated to reduce cerebral lysine flux (cation transporter competitive inhibition).. Results: Lysine-restriction was well tolerated and diet is safe, resulted in reduction of lysine intermediates in all body fluids in all patients (up to 80% reduction AASA in cerebrospinal fluid), with beneficial effects on seizure control and psychomotor development. Additional arginine fortification resulted in normalization of biomarkers and dramatic improvement of psychomotor development. Discussion: Triple therapy is effective, especially if implemented early; studies for PDE newborn screening have been initiated. For dissemination and evidence generation, our PDE Consortium published Recommendations, developed a Digital Diet App and established a RedCap study database (www.pdeonline.org).

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.

Background: Term neonates with congenital heart disease (CHD) demonstrate a high incidence of white matter injury (WMI), together with increased average diffusivity and decreased fractional anisotropy (FA) on MR diffusion tensor imaging. EEG background activity is a robust measure of functional brain maturation that becomes less discontinuous, contains more fast activity and shows higher complexity of EEG patterns with increasing age. We sought to determine the association between structural brain abnormalities and functional brain maturation in term neonates with CHD. Methods: Thirteen term newborns with CHD underwent pre-operative MR imaging and continuous EEG recordings (cEEG). The proportion of cEEG with discontinuous vs. continuous background activity was quantified by visual analysis. During continuous epochs, we differentiated between two states: wakefulness/active sleep vs. quiet/transitional sleep, and applied algorithms to measure spectral power and EEG complexity. Results: Three patients had multifocal WMI which was associated with greater EEG background discontinuity (P<0.05). Moreover, lower white matter diffusivity was associated with higher power of fast activity (P<0.05 for wakefulness/active sleep EEG pattern), while higher white matter FA showed a trend toward being associated with increased EEG complexity (P<0.1 for quiet/transitional sleep pattern). Conclusions: In this series of term neonates with CHD, structural and microstructural white matter abnormalities are associated with impaired maturation of brain function.

Background: It has been hypothesized that [18F]-sodium fluoride (NaF) uptake imaged with positron emission tomography (PET) binds to hydroxyapatite molecules expressed in regions with active calcification. Therefore, we aimed to validate NaF as a marker of hydroxyapatite expression in high-risk carotid plaque. Methods: Eleven patients (69 ± 5 years, 3 female) scheduled for carotid endarterectomy were prospectively recruited for NaF PET/CT. One patient received a second contralateral endarterectomy; two patients were excluded (intolerance to contrast media and PET/CT misalignment). The bifurcation of the common carotid was used as the reference point; NaF uptake (tissue to blood ratio - TBR) was measured at every PET slice extending 2 cm above and below the bifurcation. Excised plaque was immunostained with Goldner’s Trichrome and whole-slide digitized images were used to quantify hydroxyapatite expression. Pathology was co-registered with PET. Results: NaF uptake was related to the extent of hydroxyapatite expression (r=0.45, p<0.001). Upon classifying bilateral plaque for symptomatology, symptomatic plaque was associated with cerebrovascular events (3.75±1.1 TBR, n=9) and had greater NaF uptake than clinically silent asymptomatic plaque (2.79±0.6 TBR, n=11) (p=0.04). Conclusion: NaF uptake is related to hydroxyapatite expression and is increased in plaque associated with cerebrovascular events. NaF may serve as a novel biomarker of active calcification and plaque vulnerability.