bluuebunny/crossref_metadata_2025 huggingface dataset:
Victor Horsley
Authors: Aminoff Michael J.
Published: January 2022

Sir Victor Horsley (1857–1916) was a pioneer who shaped the development of neurosurgery and the direction of clinical medicine through his work with the British Medical Association, Medical Defence Union, and General Medical Council. Before the nervous system could be imaged, Horsley operated successfully on the brain and spinal cord, and performed palliative procedures on patients dying from brain tumours. Nevertheless, he became a social pariah due to his support for nationalised health insurance, child welfare and women's rights, amongst other causes. In this fascinating biography, leading neurologist Dr Michael J. Aminoff places Horsley's life and work in the context of the society in which he lived and explores his influence on the development of neurosurgery and social policies still in effect. The many underlying themes to the book include the interplay of science and politics, and the responsibility of physicians to themselves and for the welfare of society.
Normative Transformation and the War on Terrorism
Authors: Pratt Simon Frankel
Published: January 2022

Pratt investigates the potential erosion of prohibiting assassination, torture, and mercenarism during the US's War on Terrorism. In examining the emergence and history of the US's targeted killing programme, detention and interrogation programme, and employment of armed contractors in warzones, he proposes that a 'normative transformation' has occurred, which has changed the meaning and content of these prohibitions, even though they still exist. Drawing on pragmatist philosophy, practice theory, and relational sociology, this book develops a new theory of normativity and institutional change, and offers new data about the decisions and activities of security practitioners. It is both a critical and constructive addition to the current literature on norm change, and addresses enduring debates about the role of culture and ethical judgement in the use of force. It will appeal to students and scholars of foreign and defence policy, international relations theory, international security, social theory, and American politics.
Classical and Quantum Statistical Physics
Authors: Heissenberg Carlo , Sagnotti Augusto
Published: January 2022

Statistical physics examines the collective properties of large ensembles of particles, and is a powerful theoretical tool with important applications across many different scientific disciplines. This book provides a detailed introduction to classical and quantum statistical physics, including links to topics at the frontiers of current research. The first part of the book introduces classical ensembles, provides an extensive review of quantum mechanics, and explains how their combination leads directly to the theory of Bose and Fermi gases. This allows a detailed analysis of the quantum properties of matter, and introduces the exotic features of vacuum fluctuations. The second part discusses more advanced topics such as the two-dimensional Ising model and quantum spin chains. This modern text is ideal for advanced undergraduate and graduate students interested in the role of statistical physics in current research. 140 homework problems reinforce key concepts and further develop readers' understanding of the subject.
Hidden Histories of Pakistan
Authors: Waheed Sarah Fatima
Published: January 2022

Censorship, Urdu literature, Islam, and progressive secular nationalisms in colonial India and Pakistan have a complex, intertwined history. Sarah Waheed offers a timely examination of the role of progressive Muslim intellectuals in the Pakistan movement. She delves into how these left-leaning intellectuals drew from long-standing literary traditions of Islam in a period of great duress and upheaval, complicating our understanding of the relationship between religion and secularism. Rather than seeing 'religion' and 'the secular' as distinct and oppositional phenomena, this book demonstrates how these concepts themselves were historically produced in South Asia and were deeply interconnected in the cultural politics of the left. Through a detailed analysis of trials for blasphemy, obscenity and sedition, and feminist writers, Waheed argues that Muslim intellectuals engaged with socialism and communism through their distinctive ethical and cultural past. In so doing, she provides a fresh perspective on the creation of Pakistan and South Asian modernity.
Theories of Institutions
Authors: Jupille Joseph , Caporaso James A.
Published: January 2022

The human condition teems with institutions – intertemporal social arrangements that shape human relations in support of particular values – and the social scientific work developed over the last five decades aimed at understanding them is similarly vast and diverse. This book synthesizes scholarship from across the social sciences, with special focus on political science, sociology, economics, and organizational studies. Drawing out institutions' essentially social and temporal qualities and their varying relationships to efficiency and power, the authors identify more underlying similarity in understandings of institutional origins, maintenance, and change than emerges from overviews from within any given disciplinary tradition. Most importantly, Theories of Institutions identifies dozens of avenues for cross-fertilization, the pursuit of which can help keep this broad and inherently diverse field of study vibrant for future generations of scholars.
Classical and Discrete Functional Analysis with Measure Theory
Authors: Buntinas Martin
Published: January 2022

Functional analysis deals with infinite-dimensional spaces. Its results are among the greatest achievements of modern mathematics and it has wide-reaching applications to probability theory, statistics, economics, classical and quantum physics, chemistry, engineering, and pure mathematics. This book deals with measure theory and discrete aspects of functional analysis, including Fourier series, sequence spaces, matrix maps, and summability. Based on the author's extensive teaching experience, the text is accessible to advanced undergraduate and first-year graduate students. It can be used as a basis for a one-term course or for a one-year sequence, and is suitable for self-study for readers with an undergraduate-level understanding of real analysis and linear algebra. More than 750 exercises are included to help the reader test their understanding. Key background material is summarized in the Preliminaries.
Gender Component of Internal Displacement in Ukraine: A Case of Business (In)Capability to Localize Human Rights Impact Assessment
Authors: Khrystova Ganna , Uvarova Olena
Published: January 2022

Human rights due diligence (HRDD) has become the buzzword of much of the advocacy and work today around business and human rights.1 It is almost commonplace that companies have the responsibility to identify, prevent, mitigate and account for how they address these adverse human rights impacts as part of their ongoing HRDD processes, in line with the UNGPs.2 The assessment of human rights impacts (HRIA) is a critical step in this process.3
GP.3 Examining Aneurysmal Healing After Flow Diversion Treatment Using
Endovascular Optical Coherence Tomography
Authors: Pasarikovski CR , Ku J , Ramjist J , Dobashi Y , Priola SM , da Costa L , Kumar A , Yang VX
Published: January 2022

Background: The mechanism of aneurysmal healing
after flow-diversion treatment of cerebral aneurysms remains unknown. The
purpose of this research to is to utilize a novel technology called
endovascular optical coherence tomography (OCT) to characterise and improve
our understanding of aneurysmal healing after flow-diversion using a rabbit
aneurysm model. Methods: Saccular aneurysms were
created in 10 New Zealand white rabbits. The aneurysms were treated with a
flow-diverting stent 28 days after creation. OCT and histopathologic
examinations included: luminal thrombosis, endothelial loss, inflammation,
fibrin, smooth muscle cell loss, disruption of the internal and external
elastic lamina, and tunica adventitia changes
Results: OCT revealed endothelialization across
the stent, appearing to originate from the parent vessel, along with small
amounts of thrombus on the stent-struts. Minimal thrombus was visualized
within the aneurysm sac. Histologic examination revealed that OCT can
accurately define endothelialization across the sent, and define patent
segments across the neck. Conclusions: Aneurysmal
healing appears to originate at the parent vessel/stent interface, and use
the stent as a scaffold to grow across the neck of the aneurysm. Minimal
thrombus was visualized within the aneurysm sac, with ongoing flow observed
in the setting of incomplete neck endothelialization. This technology has
great potential for assessing aneurysmal healing in real-time.
B.5 Hospitalization in school aged children with cerebral palsy and
population-based Controls: A Data Linkage Study
Authors: Fortin O , Ng P , Dorais M , Koclas L , Pigeon N , Shevell M , Oskoui M
Published: January 2022

Background: Predictors of hospitalization and
reasons for admissions can inform healthcare planning and prevention. We
sought to characterize the hospitalization pattern and risk factors for
admission of children with cerebral palsy (CP).
Methods: Data from the Registre de
paralysie cérébrale du Québec and provincial
administrative databases were linked. The CP cohort contained children born
between 1999 and 2002. Data related to admissions were captured in 2012.
Relative risks (RR) were calculated to identify factors increasing
hospitalization risk. Peers without CP were matched from administrative
databases in a 20:1 ratio. Chi-square tests and Student’s T-tests were used
to compare cohorts. Results: 301 children with CP and
6040 peer controls were selected. Hospitalizations were increased in
children with CP (raw mean difference (RMD) 5.0 95% CI 4.7 to 5.2), with
significantly longer lengths of stay (RMD 2.8 95% CI 1.8 to 3.8) and number
of diagnoses per hospitalization (RMD 1.6 95% CI 1.4 to 1.8). Increased risk
of any hospitalization was observed in children with a more complex profile.
Conclusions: Children with a more severe profile
of CP and greater health care complexity face more frequent and longer
hospital stays. Coordinated interdisciplinary care is needed in school-aged
children with CP and medical complexity.
B.7 Nutrition in the first two weeks of life, neonatal brain growth and
cognitive outcomes in children born very preterm
Authors: Hadjinicolaou A , Gomaa N , Kwan E , Chau V , Schneider J , Synnes A , Grunau R , Miller S
Published: January 2022

Background: Nutrition in early life plays a
critical role in the growth and neurodevelopment of preterm neonates.
However, whether early nutrition modified the association of white matter
injury (WMI) with brain maturation and neurodevelopmental outcomes remains
unclear. Methods: In this prospective cohort study,
very preterm neonates were recruited from the NICU at BC Women’s Hospital.
MRI and measures of NAA/choline were obtained. Energy intake was recorded
over the first two weeks of life and the cohort was dichotomized.
Neurodevelopmental outcomes were assessed at 4.5 years of age using
WPPSI-III. Results: Neonates in the high lipid group
had higher levels of NAA/choline in the basal ganglia. When accounting for
confounders, this relationship was only significant in neonates without WMI
(p=0.04).

Overall, neonates with larger WMI volumes had lower IQ scores at 4.5
years (p<0.001). However, this relationship was attenuated in the high
lipid group (p=0.002) relative to the lower lipid intake group.
Conclusions: In this cohort, higher energy intake
is associated with increased brain maturation. Similarly, neonates with
large WMI had higher full-scale IQ if they received greater lipid intake in
the neonatal period, suggesting that greater early lipid intake may
contribute to blunting the deleterious effects of WMI on neurodevelopmental
outcomes.
P.009 Improving Detection of Creutzfeldt-Jakob Disease Mimics in Clinical
Practice
Authors: Lazar ES , Porter AL , Prusinski CC , Dunham S , Lopez-Chiriboga A , Hammami M , Dubey D , Day GS
Published: January 2022

Background: Assays capable of detecting prions in
CSF (e.g., RT-QuIC) have greatly improved the antemortem diagnosis of
Creutzfeldt-Jakob disease (CJD) yet take time to conduct and are not widely
accessible. There is a need to identify clinical features and common tests
that identify mimics at presentation. Methods: Mimics
were identified within longitudinal studies of rapidly progressive dementia
at study sites. Mimics met clinical criteria for probable CJD but did not
have CJD. Clinical features were compared between mimics and patients with
CJD assessed at Mayo Clinic Enterprise (n=79) and Washington University in
St. Louis (n=10; Jan-2014 to Oct-2020). Results:
Mimics (10/155; 6.5%) were diagnosed with autoimmune encephalitis (n=7),
neurosarcoidosis, frontotemporal lobar degeneration with motor neuron
disease, and unknown dementia. Age-at-symptom onset, gender, presenting
symptoms, and EEG and MRI findings were similar between mimics and CJD
patients. Focal motor abnormalities (49/93, 10/10), elevations in CSF
leukocytosis (4/92, 5/10) and protein (39/92, 9/10) were more common in
mimics (p<0.01). Neural-specific autoantibodies associated with
autoimmune encephalitis were detected within the serum (4/9) and CSF (5/10)
of mimics, but not CJD cases. Conclusions: Autoimmune
encephalitis, neurosarcoidosis and neurodegenerative diseases may mimic CJD
at presentation and should be considered in patients with early motor
dysfunction and abnormal CSF studies.
P.012 SketchNet: Equipping Cognitive Examinations With Neural Network
Computer Vision
Authors: Howard C
Published: January 2022

Background: With the advance of technology, our
capacity to assess patients with dementia is also developing. It is possible
to administer cognitive examinations using technology, such as the
iPad-based Toronto Cognitive Assessment, but hitherto difficult to
autonomously administer them. Many of the ’inputs’ from patients could be
easily scored with software, but highly variable inputs such as the clock
drawing are extremely difficult to score, precluding automated
administration and scoring. This work focuses on the development of a neural
network designed to assess cube drawings, infinity drawings, and clock
drawings. Methods: 3200 drawings, evenly split
between clocks, cubes and infinities were generated, with half being correct
and half incorrect. A SqueezeNet was trained on 2000 images, validated on
800 drawings, and then tested on 400 drawings.
Results: The SqueezeNet was able to achieve 97%
accuracy on 400 images it had never seen before in categorizing images as
“Cube”, “Clock”,

“Infinity”, or “Other” (incorrectly drawn).
Conclusions: This neural network can successfully
determine the difference between correctly and incorrectly drawn images
commonly used in cognitive examinations, overcoming the final barrier to
autonomously administering and scoring cognitive examinations. Next steps
are to clinically validate an autonomous examination program which has been
modeled after the Addenbrooke Cognitive Examination-3.
P.030 Long-term Safety and Tolerability of Atogepant 60 mg Following
Once-Daily Dosing Over 1 Year for the Preventive Treatment of
Migraine
Authors: Ashina M , Tepper SJ , Reuter U , Blumenfeld AM , Hutchinson S , Xia J , Davidovic G , Miceli R , Severt L , Finnegan M , Trugman JM
Published: January 2022

Background: The goal of the study was to assess
the safety and tolerability of atogepant, an oral, calcitonin gene-related
peptide receptor antagonist in development for migraine preventive
treatment, once daily over 1 year. Methods:
Multicenter, open-label trial (NCT03700320). Adults with migraine were
randomized 5:2 to atogepant or oral standard-of-care (SOC) migraine
prevention. Results: 744 randomized participants
(n=546 atogepant), 739 safety population participants (n=543 atogepant).
Adverse events (AEs) were reported by 67.0% of atogepant participants; 18.0%
had AEs considered related to atogepant. AEs reported by ≥5% of
atogepant-treated participants were upper respiratory tract infection
(10.3%), constipation (7.2%), nausea (6.3%), and urinary tract infection
(5.2%). 4.4% of atogepant participants reported serious AEs that included
various, common medical conditions; no event occurred in ≥1 participant and
none were atogepant-related. Two deaths were reported in atogepant-treated
participants (homicide victim; toxic shock syndrome); both were considered
not treatment-related. 5.7% of atogepant participants discontinued due to
AEs. Alanine aminotransferase/aspartate aminotransferase levels ≥3X upper
limit of normal were reported for 2.4% of atogepant participants (n=13/531)
and 3.2% of SOC participants (n=6/190). No cases of potential Hy’s Law were
reported. Conclusions: Once-daily use of atogepant
for preventive treatment of migraine over 1 year was safe and well-tolerated
with no safety concerns identified.
P.067 A worldwide survey of physician approaches to patients with acutely
symptomatic carotid stenosis (“hot carotid”)
Authors: Ganesh A , Jewett G , Campbell DJ , Singh R , Al-Sultan A , Wong J , Menon BK
Published: January 2022

Background: Patients with acutely symptomatic
carotid stenosis (“hot carotid”) have high up-front risk of recurrent
strokes. Uncertainties remain regarding optimal anti-thrombotic management,
particularly while awaiting revascularization with endarterectomy or
stenting (CEA/CAS). Methods: We administered a
worldwide electronic survey through Neurology: Clinical
Practice. Respondents chose their preferred antithrombotic
regimen (1) in a general case of acutely symptomatic carotid stenosis, (2)
if the patient was already on aspirin, or (3) had associated intraluminal
thrombus(ILT). Responses among different groups were compared using
multivariable logistic regression. Results: We
received 668 responses from 71 countries. Most respondents favoured
CEA(69.1%) over CAS, an aspirin-containing regimen(88.5%), and a
clopidogrel-containing regimen(64.4%) if already on aspirin. Monotherapy was
favoured by 54.4-70.6% across scenarios. The preferred dual therapy was
low-dose aspirin(75-100mg) plus clopidogrel(22.2%), or high-dose
aspirin(160-325mg) plus clopidogrel if already on aspirin(12.2%).
Respondents favouring CAS more often chose ≥2 agents (adjusted
odds-ratio[aOR] vs CEA: 2.00, 95%CI 1.36-2.95,p=0.001) or
clopidogrel-containing regimens (aOR:1.77,1.16-2.70,p=0.008). Respondents
from Europe less commonly chose multiple agents (aOR vs United
States/Canada: 0.57,0.35–0.93,p=0.023) while those from Asia more often
favored multi-agent regimens (aOR:1.95,1.11–3.43,p=0.020).
Conclusions: Our results highlight the
heterogeneous anti-thrombotic management of hot carotids. Future trials
should likely include high-dose aspirin monotherapy or low-dose
aspirin/clopidogrel dual-therapy as a comparator arm to stimulate
enrolment.
P.090 Evaluation of Mutant Alleles of Engrailed and Invected in
Drosophila Melanogaster Models of Parkinson Disease
Authors: Smith SV , Staveley BB
Published: January 2022

Background: Parkinson Disease (PD) is a
neurodegenerative disorder, resulting in a gradual decline in voluntary
movement, where lifespan remains stable. Drosophila
melanogaster offer comparable gene sequences to those
targeted in PD; among them are two transcription factors,
engrailed (en) and
invected (inv).
Methods: Wild-type homozygous allele
Oregon-R(en+,
inv+)
was compared to heterozygous mutants of
en1,
en4,
en7,
en54,
en58,
invW,
inv30, and
Df (2R)
enEinvE.
Nine climbing and aging studies were executed from crosses with
w1118(en+,
inv+)
as the maternal genotype. Results:
Independent-samples t-tests were conducted to compare the percent survival
(in days). No significant differences were observed between the experimental
groups and the control group. A mixed Analysis of Variance was conducted to
compare climbing behaviour over time (in weeks) for all nine groups. Both
main effects (group, time), and the interaction (group x time) were
significant. Post hoc Fisher’s Least Significant Difference tests revealed a
significant difference between the control group and
en1,
en4,
en54,
invW, and
Df (2R)
enEinvE
groups. Conclusions: These results support the
hypothesis that mutations of en, inv, or both
will result in a PD phenotype and consequent decreased motor function of
D. melanogaster PD models, with or without a
significant decrease in lifespan.
P.094 Referral Practices for Epilepsy Surgery in Pediatric Patients: A
North American Study
Authors: Buttle SG , Muir K , Dehnoei S , Webster R , Tu A
Published: January 2022

Background: The International League Against
Epilepsy recommends patients with drug resistant epilepsy (DRE) be referred
for surgical evaluation, however prior literature suggests this is an
underutilized intervention. This study captures practices of North American
pediatric neurologists regarding the management of DRE and factors which may
promote or limit referrals for epilepsy surgical evaluation.
Methods: A REDCap survey distributed via the
Child Neurology Society mailing list to pediatric neurologists practicing in
North America. “R” was used to conduct data analyses. Ethics approval from
the CHEO REB was granted prior to the start of data collection.
Results: 102 pediatric neurologists responded,
77% of whom currently practice in the United States. 73% of respondents
reported they would refer a patient for surgical consultation after two
failed medications. Of all potential predictors tested in a logistic
regression model, low referral volume was the only predictor of whether
participants refer patients after more than three failed medications.
Conclusions: Pediatric neurologists demonstrate
fair knowledge of formal recommendations to refer patients for surgical
evaluation after two failed medication trials. Other modifiable factors
reported, especially family perceptions of epilepsy surgery, should be
prioritized when developing tools to enhance effective referrals and
increase utilization of epilepsy surgery in the management of pediatric
DRE.
P.100 A Retrospective Study of Alberta Emergency Room Utilization by
Pediatric Epilepsy Patients
Authors: Kassiri J , Mailo J , Rajapakse T , Wang GT , Liu N , Richer L , Sinclair DB
Published: January 2022

Background: Epilepsy, a common neurologic
condition, instigates a large number of emergency room (ER) visits annually.
This project aims to retrospectively review the patterns and characteristics
of Alberta ER visits by pediatric epilepsy patients.
Methods: Methods: Alberta Health administrative
databases, including the Inpatient Discharge Abstract Database, the National
Ambulatory Care Reporting System, Diagnostic Imaging and Medical Laboratory,
were used to identify ER utilization patterns among children with epilepsy
in Alberta, Canada between 2012–2018. Results:
Results: Of 5,419 pediatric epilepsy ER patients between 2012–2018 in
Alberta, 59% were developmentally delayed children. Children in this
particular group, when compared to developmentally normal children with
epilepsy, had the following characteristics: they were significantly more
likely to utilize ERs in children’s hospitals versus other hospitals; they
presented at a significantly younger age; they had a significantly longer
length of stay; they had higher triage scores; they were subjected to
significantly more investigations; and they had significantly more hospital
admissions for epilepsy. Conclusions: Discussion:
This novel Alberta-wide study of resource utilization of pediatric epilepsy
patients shows that developmentally delayed children with epilepsy use
significantly higher resources compared to developmentally normal children
with epilepsy. Whether this is justified or not requires further
study.
P.119 Emergency Department Use in Children with Cerebral Palsy: A Data
Linkage Study
Authors: Fortin O , Ng P , Dorais M , Koclas L , Pigeon N , Shevell M , Oskoui M
Published: January 2022

Background: Improved understanding of factors
predictive of emergency department (ED) visits in children with cerebral
palsy (CP) can help optimize healthcare use. We sought to identify the
pattern of ED consultations in these children.
Methods: Data from the Registre de
paralysie cérébrale du Québec and provincial
administrative databases were linked. The CP cohort was comprised of
children born between 1999 and 2002. Data pertaining to ED presentations
between 1999 and 2012 were obtained. Relative risks were calculated to
identify factors associated with increased ED visits. Peers without CP were
selected from administrative databases and matched in a 20:1 ratio.
Chi-square tests and Student’s T-tests were used to compare the two cohorts.
Results: 301 children with CP and 6040 peer
controls were selected. Ninety-two percent (92%) of the CP cohort had at
least one ED visit, compared to 74% amongst controls. Children with CP had
an increased risk of high ED use compared to peers (RR 1.40 95% CI
1.30-1.52). Factors predictive of high ED use were comorbid epilepsy, severe
motor impairment and low socioeconomic status.
Conclusions: Children with CP have a higher need
for urgent health assessments than their peers, resulting in increased use
of ED services. System factors and barriers should be investigated.
P.122 The Pediatric Neuroirritability Management Protocol at the Stollery
Children’s Hospital – Inspired by an Irritable Infant with GM3 Synthase
Deficiency
Authors: Ng C , Rapoport A , Rajapakse T , Kassiri J , Liu N , Goez H , Yager J , Wren T , Richer L , Sinclair D , Mailo J
Published: January 2022

Background: We describe an infant with a
diagnosis of GM3 synthase deficiency, presenting with severe
neuroirritability from birth. He required multiple admissions due to extreme
agitation and caregiver burnout. Multiple pharmacological agents were tried,
and the effect of each medication was modest and short-lasting at best. The
literature on the management of neuroirritability in children with
progressive genetic and metabolic conditions is sparse, and a
neuroirritability management protocol has yet to be developed at our
institution. Methods: We searched for relevant
primary research and articles on PubMed. We reviewed the evidence of each
pharmacological agent and added non-pharmacological strategies. We developed
management guidelines for neuroirritability at our hospital. This protocol
was reviewed by several pediatric neurologists and pediatric palliative care
specialists at the Stollery and SickKids Hospitals.
Results: We present the Pediatric
Neuroirritability Management Protocol for the Stollery Children’s Hospital.
Conclusions: Further study is required to assess
whether this protocol can be adapted to treat irritability in the context of
other neurological conditions such as hypoxic-ischemic encephalopathy and
non-accidental injury. In addition, we will expand our guidelines to include
other symptoms such as spasticity, dystonia, and autonomic
dysfunction.
P.126 Incorporation of Objective Structured Clinical Examination into
EEG/Epilepsy Fellowship Training
Authors: Myers K
Published: January 2022

Background: For over 40 years, the objective
structured clinical examination (OSCE) has been a part of medical education,
eventually finding its way into most aspects of clinical training and
evaluation. However, the EEG/epilepsy fellowship training has not
classically involved OSCE evaluations. Methods: We
designed and implemented a formative OSCE for pediatric and adult
EEG/epilepsy fellows in Montreal, Quebec, Canada. The examination was
offered in French and English. Stations included: technical issues, short
cases, a long case, and communication. We solicited post-examination
feedback from all participants via anonymous electronic survey after they
had completed the Canadian Society for Clinical Neurophysiology (CSCN) EEG
examination. We asked questions surrounding utility of the examination,
areas for improvement, and whether the participant had been successful in
passing the CSCN examination. Results: Six fellows
took the initial formative OSCE. All six reported passing the subsequent
CSCN examination. All participants reported the OSCE as useful in
examination preparation. The communication station was consistently ranked
as the least useful station, an unsurprising finding given that the CSCN
examination does not involve a communication component.
Conclusions: OSCE is an effective tool in
assessment of the level of competence of EEG/epilepsy fellows, and as
preparation for the CSCN EEG examination.
P.130 Clinical prognostic factors in adult intracranial ependymoma
patients – A fifty year multi-institutional experience
Authors: Zuccato JA , Algan O , Nair V , Gunter T , Glenn CA , Dunn IF , Fung K , Shultz DB , Zadeh G , Laperriere N , Tsang DS
Published: January 2022

Background: Standard of care treatment for adult
intracranial ependymoma patients includes maximal safe surgical resection,
while the role for adjuvant radiotherapy remains unclear with existing data
from small retrospective series’. Accordingly, we built a
multi-institutional cohort to assess the prognostic value of adjuvant
radiotherapy and other clinical factors in these patients.
Methods: Patients managed for adult intracranial
ependymomas from 1968 onwards within the University Health Network in
Toronto, The University of Oklahoma Health Sciences Center, and The Ottawa
Hospital were identified. Multivariate models assessing the prognostic value
of clinical factors were built using variables with known prognostic value
and/or significance in univariate Cox models.
Results: Of 122 ependymomas, 71% were
infratentorial, 78% grade two, 55% gross/near-totally resected (GTR/NTR),
and 65% treated with adjuvant radiotherapy. Multivariate analyses identified
GTR/NTR (vs. subtotal resection; HR=0.2, 95%CI=0.1–0.4, p<0.0001) and
cranial (HR=0.5, 95%CI=0.2–1.1) or craniospinal (HR=0.2, 95%CI=0.04–0.5)
radiotherapy receipt (p=0.01) as independent statistically significant
predictors of more favourable PFS. Grade II pathology (vs. grade III;
HR=0.2, 95%CI=0.05–0.6, p=0.006) and GTR/NTR (vs. subtotal resection;
HR=0.1, 95%CI=0.03–0.3, p=0.0001) were independent statistically significant
predictors of better OS. Conclusions: This work
confirms the importance of maximal safe resection for adult intracranial
ependymomas and establishes that adjuvant radiotherapy improves
progression-free survival in these patients.
P.137 A qualitative study of families’ experiences with medical
assistance in dying (MAiD) in Nova Scotia
Authors: Leck E , Jackson-Tarlton C , Crumley E , Gubitz G
Published: January 2022

Background: MAiD became legal in Canada in 2015,
with Bill C-14 delineating eligibility criteria and access. Previous
research found families are intimately involved with decision-making, with
conflicting perspectives on how they cope.

Our study sought to learn about the experiences of family members, and
determine what supports might be beneficial to improve MAiD delivery and
aftercare. Methods: We conducted hour-long
semi-structured interviews with 20 family members of individuals who had
MAiD. Interviews took place by telephone or virtually via MS Teams, and
transcripts were analyzed using an iterative coding process and thematic
analysis. Results: Prominent themes emphasized the
importance of respecting autonomy, decision-making, and allowing people to
regain a sense of control, particularly with so much taken away.

The death itself was described as peaceful. Interviewees were
overwhelmingly filled with relief and gratitude for being able to respect
the individual’s wishes.

Interviewees spoke of importance of support for themselves, and the
desire to build a network of individuals with similar experiences; to share
their stories, grieve together, and support the next generation.
Conclusions: These results will help improve MAiD
delivery and aftercare in Nova Scotia, by informing, developing and enabling
access to resources for individuals who accompany a family member on their
end-of-life journey.
P.140 Radiological characteristics of brain metastases in non-small cell
lung cancer relative to EGFR mutation status
Authors: Hashmi O , Younus H , Bolton L
Published: January 2022

Background: Approximately 20-40% of patients with
non-small cell lung cancer (NSCLC) will develop brain metastases (BM). The
aim of this study was to investigate if Epidermal Growth Factor Receptor
(EGFR) status of NSCLC alters the radiological appearances of BM. Also to
compare differences in imaging features of BM occurring from EGFR-mutated
NSCLC during treatment with Tyrosine Kinase Inhibitors (TKI) versus prior to
treatment. Methods: A retrospective study was
performed over a 5 year period of all patients with histologically proven
NSCLC with BM and known EGFR status. 72 patients met the inclusion criteria.
Radiological features were reviewed as well as number, size and location of
BM. Results: 18/72 patients had EGFR-mutated NSCLC
and of these 9 presented with BM while on TKI treatment. Patients with
EGFR-mutated NSCLC had statistically significant higher occurrence of
multiple BM (p=0.029) and BM in a central location (p=0.027). BM that
occurred during TKI treatment appeared smaller and with minimal surrounding
oedema. Conclusions: Given the propensity for
multiple BM in EGFR-mutated NSCLC, vigilant imaging follow up would need to
be considered. BM presenting while on TKI were more subtle, especially on
Computed Tomography (CT), therefore careful follow up with Magnetic
Resonance Imaging (MRI) may be required.
P.148 Children and teenagers with hydrocephalus: Are narrowed dural
sinuses better predictors of shunt-failure than ventriculomegaly?
Authors: Rohr B , Sorensen J , Gong B , Jansen O , Rohr A
Published: January 2022

Background: Intracranial hypertension secondary
to shunt-failure is a feared complication requiring cross-sectional imaging
for diagnosis. We compared dural sinus narrowing and ventriculomegaly as
predictors of shunt-failure. Methods: 60 head MRIs
and 60 MR venographies of hydrocephalus patients age 0-18 years (n=25) were
analyzed. MRI studies were included when f/u clinical data combined with
intra-operative findings proved shunt-failure (positive Gold standard) or
when MRI was available when the child was well (negative Gold standard). The
absence or presence of concerning hydrocephalus was diagnosed. On MRV, the
major dural sinuses were independently analyzed with respect to >50%
narrowing, suggesting compression by increased CSF pressure.
Ventriculomegaly and significant dural sinus narrowing was correlated to the
presence/absence of shunt failure as per Gold standard.
Results: Sinus narrowing substantially correlated
with proven shunt-failure (Cohen’s kappa test 0.635/p<=0.00001 as per
Fisher exact test) while ventriculomegaly correlated poorly
(0.258/p=0.0751). Sensitivity/specificity was 0.69/0.92 for sinus narrowing
and 0.43/0.81 for ventriculomegaly. Conclusions: In
this patient cohort, dural sinus narrowing more reliably predicted
shunt-failure compared to ventriculomegaly.
P.150 Use of Antibacterial Envelopes for Prevention of Infection in
Neuromodulation
Authors: Persad A , Ahmed S , Mercure-Cyr R , Waterhouse K , Vitali A
Published: January 2022

Background: Neuromodulation unit placement
carries a historic infection rate as high as 12%. TYRX antibacterial
envelopes (Medtronic Inc., Minneapolis, MN), which are absorbable mesh
envelopes that elute minocycline and rifampin, have been used in implantable
cardiac devices with substantial risk reduction for infection.
Methods: We conducted a retrospective cohort
study of consecutive implantable pulse generator (IPG) and intrathecal pump
unit implantation with a TYRX antibacterial envelope©. This cohort was then
compared to a historical cohort of consecutive patients undergoing IPG or
pump placement or revision prior to the use of the envelopes.
Results: In the pre-envelope cohort of 151 IPGs
in 116 patients, the infection rate was 18/151 (11.9%). In the antibacterial
envelope cohort of 233 IPGs in 185 patients, the infection rate was (2.1%).
The absolute risk reduction was 4.6% (95% CI, 0.045-0.048), The pre-envelope
cohort of 41 pumps in 39 patients, the infection rate was 6/41 (14.6%). In
the antibacterial envelope cohort of 59 pumps in 54 patients, the infection
rate was (1.7%). The absolute risk reduction was 12.9% (95% CI 1.6-24.3).
Conclusions: Usage of an antibacterial envelope
for neuromodulation has resulted in a lower infection rate at our center.
Based on these results, we recommend the use of antimicrobial
envelopes.
P.157 Frame-based stereotactic brain biopsy: A retrospective review of
diagnostic yield and complications at a Canadian Center
Authors: Gariscsak PJ , Gui C , Lau JC , Megyesi JF
Published: January 2022

Background: Historically, frame-based
stereotactic brain biopsy (SBB) has played an important role in the
diagnosis of intracranial lesions. We performed a single centre analysis of
the outcomes and efficacy of SBB at the London Health Sciences Centre
(LHSC). Methods: We performed a retrospective chart
review of frame-based SBB from 2006 to 2017 at the LHSC. Intra-operative and
final pathology reports were analyzed for biopsy diagnosis and the diagnosis
was compared with pre-operative neuroimaging reports for correlation.
SBB-associated morbidity and mortality were investigated using chart review
and post-operative neuroimaging. Results: 173
consecutive patients were identified. The overall morbidity rate was 8.7%
(15 cases) and mortality rate was 0.6% (1 case). Final biopsy diagnostic
accuracy was 96%, intra-operative diagnostic accuracy was 94% and
pre-operative imaging diagnostic accuracy was 65%. Elevated partial
thromboplastin time and the presence of hemorrhage on post-operative CT were
associated with neurological morbidity and mortality. The need to obtain
three or greater samples the time of biopsy was associated with
non-diagnostic biopsy. Conclusions: At the LHSC, SBB
is a relatively safe and effective surgical procedure with high diagnostic
yield and relatively low risk of complications. Intra-operative pathology
has a high efficacy in determining diagnosis when compared to final
pathology.
P.159 Association Between Extent of Resection and Survival in Pediatric
Patients with High-Grade Glioma: A Systematic Review and
Meta-Analysis
Authors: Hatoum R , Chen J , Lavergne P , Shlobin N , Wang A , Dodin P , Couturier C , Ibrahim G , Fallah A , Wang A , Jabado N , Weil A
Published: January 2022

Background: While pediatric high-grade glioma
(HGG) has a poor prognosis, the relationship between extent of resection
(EOR), tumor location, and survival remains unclear. Our aim is to determine
whether gross-total resection (GTR) is associated with prolonged survival
relative to subtotal resection (STR) and biopsy.
Methods: PubMed, Ovid EBM Reviews, Embase, and
MEDLINE were systematically reviewed. Eligible articles were included for
study-level and individual-patient data (IPD) meta-analysis. Difference by
study-level and IPD characteristics were estimated using subgroup
meta-analysis and meta-regression. PRISMA guidelines were followed.
Results: In total, 33 studies were included.
Study-level meta-analysis found GTR conferred decreased mortality relative
to STR at 1 year (RR=0.73, 95%CI=0.59-0.89) and 2 years (RR=0.74,
95%CI=0.64-0.84). STR did not demonstrate survival advantages compared to
biopsy at 1 year (RR=0.81, 95%CI=0.64-1.03), but showed decreased mortality
at 2 years (RR=0.90, 95%CI=0.82-0.99). IPD meta-analysis comprised 186
patients, and indicated that STR (HR=2.61, 95%CI=1.56-4.38) and biopsy
(HR=2.83, 95%CI=1.54-5.19) had shortened survival relative to GTR, with no
differences between STR and biopsy (HR=0.93, 95%CI=0.55-1.56). In subgroup
analysis, GTR was associated with prolonged survival for hemispheric tumors
(HR=0.16, 95%CI=0.07-0.36) Conclusions: Among
pediatric patients with HGGs, GTR was independently associated with better
overall survival compared to STR and biopsy, especially in patients with
hemispheric tumors.
P.161 Management of recurrent glioblastoma multiforme: An inter-observer
variability study
Authors: Patel M , Au K , Mehta V , Broad R , Chow MM , Hockley A , Kaderali Z , Magro E , Nataraj A , Scholtes F , Chagnon M , Gevry G , Raymond J , Darsaut TE
Published: January 2022

Background: A significant proportion of
glioblastoma multiforme (GBM) patients are considered for repeat resection,
but evidence regarding best management remains elusive.
Methods: An electronic portfolio of MR images of
37 cases of pathologically confirmed recurrent GBM with an accompanying
clinical vignette was constructed. Surgical responders from various
countries, training backgrounds, and years’ experience were asked for each
case to select: their chosen management (repeat surgery, chemotherapy,
radiation, or conservative), confidence in recommended management, and
whether they would include the patient in a randomized trial that gave a 50%
chance of re-operation. Responses were evaluated with kappa statistics and
values interpreted according to Landis and Koch (0–0.2, slight; 0.21–0.4,
fair; 0.41–0.6, moderate; 0.61–0.8, substantial; 0.81-1.0 perfect
agreement). Results: 26 surgeons responded to the
survey. Agreement regarding best management of recurrent GBM was slight,
even when management options were dichotomized (repeat surgery vs. all
others) (k=0.198 (95%CI 0.133-0.276). Country of practice, years’
experience, and training background did not improve agreement. Responders
were willing to include more than 70% of patients in a randomized trial.
Conclusions: Only slight agreement exists
regarding the question of re-operation for patients with recurrent GBM. This
supports the need for a randomized controlled trial.
P.199 Variability descriptors of cerebral blood flow velocity as
predictors of vasospasm in Subarachnoid Hemorrhage: A feasibility
study
Authors: Rodriguez RA , Herry C , English S , Ramsay T , Seely A , Kenny GP , Hogan M , Meade R , Shamy M
Published: January 2022

Background: Transcranial Doppler (TCD)
measurements poorly predict vasospasm in patients with aneurysmal
subarachnoid hemorrhage (aSAH). Variability descriptors of mean cerebral
blood flow velocity (mean-CBFV) may improve this prediction. We assessed the
feasibility of generating reliable mean-CBFV variability metrics using
extended TCD recordings in aSAH patients and healthy controls. We also
explored whether these parameters are capable to discriminate aSAH patients
from healthy controls, and between patients with and without vasospasm.
Methods: Bilateral mean-CBFV, systemic blood
pressure and heart rate were recorded for 40 minutes in 3 groups: aSAH
patients (n=8) within the first 5 days post-ictus, age-matched healthy
controls (n=8) and young healthy controls (n=8). We obtained linear
[standard deviations, coefficient of variations, very-low, low and
high-frequency power-spectra] and non-linear [Fractality, deterministic
Chaos analyses] variability metrics. Results: All TCD
recordings provided consistent variability metrics. aSAH patients showed
higher correlation dimensions, increased high-frequency spectral power, and
decreased very-low frequency power than healthy controls. aSAH patients who
developed vasospasm (n=3) showed higher mean-CBFV and lower coefficient of
variations than those without vasospasm (n=5).
Conclusions: Descriptors of mean-CBFV variability
may distinguish between aSAH patients with and without vasospasm. Future
studies are required to evaluate the role of these variability parameters
for risk stratification in aSAH.
P.202 Image-Guidance for Ventricular Drains Insertion: A Systematic
Review and Metanalysis
Authors: Aljoghaiman M , Bergen B , Takroni R , Sharma S
Published: January 2022

Background: The use of Image-guidance to improve
the accuracy during ventricular drain insertion has been attempted. We aim
to assess the effect of use of Image-guidance on accuracy, drain failure
rate and number of ventricular cannulation attempts.
Methods: MEDLINE, EMBASE and Cochrane Library
databases were searched from inception to February 2021 looking for studies
comparing image-guided versus freehand ventricular drain insertion. Two
reviewers independently screened studies, extracted data and assessed risk
of bias and quality of evidence. Metanalysis was conducted in compliance
with PRISMA guidelines using a random-effects model and GRADE tool was used
to assess quality of evidence. Results: 17 studies
with 3404 patients were included, all of which were of non-randomized
design. Pooled data on drain accuracy and drain failure rates showed
favourable effect of image-guidance with risk ratio of 1.31 (95% CI of 1.13
– 1.51, low quality evidence) and 0.63 (95% CI 0.48 – 0.83, moderate quality
evidence), respectively. Pooled data were equivocal for number of attempts
with mean difference score of -0.11 times (95% CI -0.31 – 0.09, very
low-quality evidence). Conclusions: Image-guidance
likely enhances drain accuracy and reduces drain failure rate. No clear
recommendation can be drawn on the benefit of intervention on number of
drain insertion attempts.
P.203 Clinical outcomes of endoscopic endonasal odontoidectomy: A single
center experience
Authors: Grose E , Moldovan ID , Kilty S , Agbi C , Lamothe A , Alkherayf F
Published: January 2022

Background: Odontoidectomy for basilar
invagination and craniovertebral junction pathology has traditionally been
performed using a transoral route. However, the endoscopic endonasal
approach to the anterior craniovertebral junction may offer safer and more
effective access when compared to transoral approaches.
Methods: This study is a retrospective chart
review of all adult patients who underwent an endoscopic endonasal
odontoidectomy at a single tertiary care center between January 2011 and May
2019. Results: Seventeen patients were included in
the study. The median admission age was 67 years (range: 33-84 years) and
65% of the patients were female. One patient (1/17, 6%) had vertebral artery
injury which was coiled with no neurological deficits, and 4 patients (4/17,
24%) had intraoperative CSF leaks with no postoperative leak. Fourteen
patients (14/17, 82%) were extubated by POD 1. Three patients (3/17, 18%)
developed postoperative sinus infections and required antibiotics. Eight
patients (8/17, 47%) developed transient postoperative dysphagia. One
patient (1/17, 6%) had postoperative epistaxis and one patient (1/17, 6%)
had postoperative lower cranial nerve symptoms. The median length of
hospital stay was 13 days (range: 2-44 days).
Conclusions: Endoscopic endonasal odontoidectomy
is a feasible and well-tolerated procedure for anterior decompression of
craniovertebral junction, associated with satisfactory patient outcomes and
low morbidity.
P.210 Transitioning from Pediatric to Adult care: a Qualitative Study of
Patients with Hydrocephalus and their Caregivers
Authors: Fouladirad S , Cheong A , Tamber MS , Singhal A , McDonald PJ
Published: January 2022

Background: Hydrocephalus is a common pediatric
neurosurgical condition that requires lifelong care into adulthood.
Significant gaps in care are thought to exist for youth transitioning to
adult care, but little is known about how patients and their caregivers feel
about the process. This study examines the perceptions of adolescents, young
adults and caregivers when transitioning from pediatric to adult care at a
single Canadian center. Methods: 40
patient/caregivers (7 adolescents, 13 young adults and 20 parents) treated
at BC Children’s Hospital participated in semi-structured interviews using
the qualitative research methodologies of grounded theory. Interviews were
transcribed verbatim and coded, with common themes identified.
Results: Four overarching themes relating to the
process of transitioning from pediatric to adult care were identified: (1):
Inadequacy of communication between pediatric and adult care teams and
patients/caregivers; (2) Uncertainty relating to the prospect of life as an
adult with hydrocephalus; (3) Anxiety and fear regarding navigating a new
health care environment; and (4) sadness at the loss relationships with the
pediatric health care team. Conclusions: We
identified a general dissatisfaction with the transitioning process for
hydrocephalus. Common themes and concerns identified may form the basis of
an improved transitioning model for youth with hydrocephalus as they become
adults.