bluuebunny/crossref_metadata_2025 huggingface dataset:
F.2 Comprehensively mapping transcriptionally relevant histone modifications in aggressive meningioma leads to novel biologic insights and therapeutic vulnerabilities
Authors: Landry AP , Patil V , Wang JZ , Nassiri F , Zadeh G
Published: May 2024

Background: We recently identified four molecular subgroups of meningioma with distinct biology and outcomes. While two (MG3/MG4) are associated with poor outcome, they display divergent transcriptional profiles (enriched in metabolic and cell cycling pathways, respectively) and therapeutic vulnerabilities (MG3 has no clear treatment target). We sought to understand drivers of these key differences at a chromatin level. Methods: We profiled MG3/MG4 meningiomas for common histone marks H3K27me3, H3K27Ac, H3K4me1, H3K4me3, H3K9me3, and H3K36me3. Multiple computational approaches were used to compare MG3 and MG4 tumours including superenhancer ranking, differential binding analysis, and unsupervised clustering. Results: Our cohort includes 11-20 meningiomas per histone mark. Clustering revealed striking separation of subgroups based on multiple histone marks, particularly H3K36me3. FOXC1, a known driver of the epithelial to mesenchymal transition, was identified as a recurrent superenhancer in both groups, whereas MG3-specific superenhancers mapped to immune regulatory networks. Integrated differential binding analysis confirmed an immune-rich microenvironment in MG3 tumours driven by multiple histone marks, suggesting a role for targeting novel immune checkpoint genes CD84 and CD48. Conclusions: This study is the first to apply integrated analysis of multiple histone modifications to aggressive meningioma. We further characterize MG3 tumours by identifying an epigenetically-driven immune phenotype and propose novel treatment targets.
P.001 Planning & decision-making in obsessive-compulsive disorder (OCD) through the lens of ERP: a comparative analysis
Authors: Kar D , Tarafder S , Goyal N
Published: May 2024

Background: This study aimed to investigate the effect of impulsivity on the planning & decision-making of individuals with OCD compared to a control group, focusing on amplitude and latency during the Tower of London (TOL) task. Methods: A sample of a total of 76 (dominantly right-handed & aged between 18-30 yrs) participated. Participants with OCD were assessed with the Y-BOCS & symptom checklist, BIS-11, and the HCs were screened with the GHQ-12. ERP components were measured by using TOL on E-prime 3.0. The amplitude and latency along with the spectral power for each problem-solving task were measured and analyzed. Results: Statistically significant differences were found in the Latency variable in the left frontal area of the brain, indicating distinctive latency patterns in individuals with OCD compared to controls. No statistically significant differences were observed in amplitude or latency for other move sequences. High spectral activity was detected in individuals with OCD for an extended period. Conclusions: Individuals with OCD exhibit higher activity indicative of ambivalence during decision-making which indicates that to overcome impulsive urges, thus they need to put more cognitive effort to maintain the same outcomes. To maintain error-free results obsessive & compulsive behaviors are a necessary evil.
P.003 Outcome of psychogenic nonepileptic seizures following diagnosis in the epilepsy monitoring unit
Authors: Abi-Nahed R
Published: May 2024

Background: study patients with PNES’ outcome after their diagnosis in the EMU. Methods: Comparative analyses were carried out on several variables before and after diagnosis: number of participants with daily PNES, number of visits to the emergency department, number of participants who took ASMs or psychotropic drugs, and employment status. Results: 61/103 patients (79% female) participated. The median age at PNES onset was 35 years. 62% were receiving ASMs and 40% psychotropic drugs. The mean stay at the EMU was five days. PNES diagnosis was explained to almost all patients (97%) by the end of their EMU stay and was well accepted by most (89%). When contacted, 46% of participants no longer had PNES; 32% mentioned that their PNES had ceased immediately upon communication of the diagnosis. Fewer patients had daily seizures after the diagnosis. Similarly, the median number of emergency department visits was significantly lower. Only 17 patients consulted their general practitioner and 20 a neurologist after a PNES attack. The use of ASMs was also significantly reduced from 70% to 33%, with only one still taking an ASM for its antiseizure properties. Conclusions: significant reductions in PNES frequency, health care utilization and ASM use.
P.005 Eptinezumab demonstrated efficacy regardless of prior preventive migraine treatment failure: post hoc DELIVER analyses
Authors: Pozo-Rosich P , Ashina M , Tepper SJ , Jensen S , Pickering Boserup L , Krog Josiassen M , Sperling B , Bougie JK , Miron J
Published: May 2024

Background: This post hoc analysis evaluated the efficacy of eptinezumab vs placebo across 24 weeks of treatment in the placebo-controlled period of the DELIVER study in subgroups defined by prior treatment failure. Methods: DELIVER (NCT04418765) randomized adults with migraine to eptinezumab 100 mg, 300 mg, or placebo intravenous infusion every 12 weeks. Eligible patients needed documented evidence of 2–4 prior preventive treatment failures within the past 10 years. This post hoc analysis focused on subgroups of patients with prior treatment failure on topiramate, beta blockers, amitriptyline, and/or flunarizine. Results: The full analysis set included 890 patients: 633 previously failed topiramate, 538 failed beta blockers, 508 failed amitriptyline, and 333 failed flunarizine; within each subgroup, most patients had 2 prior treatment failures (51–56%). Across Weeks 1–12 in all subgroups, patients treated with eptinezumab experienced greater reductions from baseline in MMDs than those receiving placebo, with larger reductions observed over Weeks 13–24. Similarly, ≥50% MRRs were higher with eptinezumab than with placebo and increased following a second infusion. Conclusions: Eptinezumab demonstrated greater reductions in MMDs compared with placebo across all subgroups of prior preventive treatment failure, with evidence to suggest that a second dose provides additional benefit.
P.009 Long-term comparative efficacy of inebilizumab from N-MOmentum participants versus azathioprine and immunosuppressants and placebo in NMOSD patients
Authors: Cree B , Suero B , Walsh S , Marignier R , Lindsey JW , Kim H , She D , Cimbora D , Patterson K , Paul F
Published: May 2024

Background: Long-term efficacy of inebilizumab (INEB), an anti-CD19+ B cell-depleting antibody approved for the treatment of seropositive-aquaporin-4-antibody (AQP4+) neuromyelitis optica spectrum disorder (NMOSD) was evaluated over N-MOmentum (NCT02200770) open-label period (OLP) vs azathioprine and other immunosuppressants (AZA/IST) and vs PBO. Methods: Two historical comparator groups (HCGs), AZA/IST (N=132) and PBO (N=106), derived from published NMOSD studies, were used to compare efficacy of INEB (N=208) over the OLP. Hazard ratios (HR) for INEB vs HCGs were estimated using Cox proportional hazards (PH) regression. Time to NMOSD attack was analysed using parametric and flexible survival (spline) models. Results: Time to NMOSD attack for N-MOmentum PBO compared to PBO was HR 1.15;(95% CI:0.67–1.91; P=0.58). The HRs for time to NMOSD attack for INEB vs AZA/IST and PBO groups were 0.29(95% CI:0.17, 0.42; P<0.001) and 0.15 (95% CI:0.10, 0.21; P<0.001). At 4 years, estimated attack-free survival was 77% (95% CI:71, 83) for INEB, 36% (95% CI:27, 46) for AZA/IST, and 12% (95% CI:7, 20) for PBO. Conclusions: INEB was associated with a statistically significant reduction in risk of an NMOSD attack and provided a long-term attack-free probability over the OLP compared to the relative short-term benefit observed with AZA/IST.
P.019 A shared decision-model toolkit for pregnancy related care in neurology
Authors: Iyengar Y , Ng S , Chan S , Sultan N , Thornton H , Patel T , Grindrod K , Krysko K , Moores G , Pikula A , Bui E
Published: May 2024

Background: Shared decision-making (SDM) is a dynamic, patient-engaged approach to collaborative medical care. Limited SDM tools exist in pregnancy. We aimed to examine the need and usability of a novel SDM tool for pharmaco-therapeutic treatment of neurological conditions in pregnancy. Methods: This is an exploratory mixed-methods study. Non-pregnant women of any age were recruited using convenience, purposive sampling from an academic neurology clinic in Toronto. Participants reported the user friendliness of the SDM by completing the systems usability (SUS) questionnaire and participated in a focus group to further elaborate on their experience. Results: Eleven participants completed the survey 45% each between age 31-40, and 51-60. Median time spent on the tool was 17.2 minutes, and median SUS score 70 (<68 being not usable). Thematic data analysis from 2 focus groups, identified technical and content improvements: use of inclusive language, simplified design, and importance of patient engagement in SDM. Conclusions: Based on our preliminary results, a SDM web-tool for medication-related concerns of pregnant patients with neurological conditions is needed and usable. With integration of patients’ lived experiences, this novel tool may serve as an anchor point for future work in this field.
P.026 Success with incrementally faster times to endovascular therapy (SWIFT-EVT): a systematic review and meta-analysis
Authors: Legere B , Mohamed A , Elsherif S , Saqqur R , Schoenfeld D , Slebonick AM , Mccartin M , Price J , Zachrison K , Edlow JA , Saqqur M , Shuaib A , Thomas S
Published: May 2024

Background: Previous research demonstrates that for acute ischemic stroke (AIS) cases, rapid endovascular therapy (EVT) performance improves outcomes. This study provides updated metrics summarizing estimates for modified Rankin Scale (mRS) gains accrued by streamlining time to EVT. Methods: A systematic review and meta-analysis (MA) was conducted using electronic databases. Eligible studies reported time-benefit slope with times from AIS onset (or time last-seen-normal) to EVT commencement; the predictor was onset-to-groin (OTG) time. Primary and secondary outcomes were 90-day functional independence (mRS 0-2) and 90-day excellent function (mRS 0-1), respectively. Results: The five included studies showed increased chance of good outcome with each hour of pre-EVT time savings for mRS 0-2 for 0-270’ (OR 1.25, 95% CI 1.16-1.35, I2 40%) and 271-360’ time frame (1.22, 95% CI 1.12-1.33, I2 58%). For studies assessing mRS 0-1, pooled effect estimates were appropriate for the 0-270’ time frame (OR 1.34, 95% CI 1.19-1.51, I2 27%) and the 271-360’ time frame (OR 1.20, 95% CI 1.03-1.38, I2 60%). Conclusions: Each hour saved from AIS onset to EVT start is associated with a 22-25% increased odds of functional independence, a useful metric to inform patient-specific and systems planning decisions.
P.031 SMILES: Sunnybrook-St. Michael’s Integrated Leadership/QI in Endovascular Stroke care – enhancing hyperacute stroke protocols for optimized door-to-intervention times
Authors: Notario L , Liu AM , Chin H , Im M , Zhuo S , Lumban A , Simec R , Abalos J , Montgomery K , Fertuck T , Lee J , Convery C , Lazo K , McMillan L , Hawkes CM , Khosravani H
Published: May 2024

Background: Hyperacute stroke care demands rapid, coordinated care. Traditional metrics like Door-to-Needle time are pivotal but insufficient for capturing the complexity of endovascular stroke interventions. The SMILES collaboration aims to standardize and optimize protocols for door-to-intervention times, incorporating Crew Resource Management (CRM). Methods: The multidisciplinary initiative integrates both hospitals, ED, neurology, and QI teams. We employed a comprehensive approach: stakeholder engagement, simulation-based learning, process mapping, and literature review. Emphasis was placed on enhancing situational awareness, triage and prioritization, cognitive load management, role clarity, effective communication, and debriefing. Results: The collaboration led to PDSA cycles and development of refined stroke protocols. Interventions included: 1) A ’zero point survey’ for team pre-arrival briefings, enhancing situational awareness and role clarity; 2) Streamlined patient registration to reduce cognitive load and improve triage efficiency; 3) Direct transfer of patients to imaging. Additionally, digital tools were implemented to facilitate communication. Simulation sessions reinforced CRM principles, leading to improved team cohesion and operational performance. Conclusions: The SMILES initiative is grounded in CRM principles by standardizing protocols and emphasizing non-technical skills crucial for high-stakes environments. This improves outcomes but also fosters a culture of safety and efficiency. Future directions include an evaluation of these protocols’ impact on patient factors.
P.034 Cost-effectiveness of treatment strategies for medically refractory pediatric epilepsy: a systematic review
Authors: Tsai P , Thirunavu VM , Govind S , Zhang L
Published: May 2024

Background: Medically refractory pediatric epilepsy is a disorder that can cause significant financial and physical burden. Although multiple treatments exist, cost-effectiveness remains unclear. We conducted a systematic review to assess cost-effectiveness of treatments for medically refractory pediatric epilepsy and to summarize key issues and areas for further inquiry. Methods: We searched MEDLINE and 6 other databases up to July 2022. We included partial and full economic evaluations (EEs) on treatments for medically refractory pediatric epilepsy. Pairs of reviewers independently screened the literature, extracted data, and assessed quality using the 24-item Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. We extracted data on study characteristics, health outcomes, model design, costs, and treatment characteristics. Results: We identified 37 eligible studies for analysis, 19 of which were partial EEs and 18 were full EEs. Study quality, outcomes reported, treatment comparators, and factors included in cost calculations were common influential factors in study results. Vagus nerve stimulation and cannabinoid oil were the most consistently cost-effective, in 6 of 7 and 1 of 2 studies, respectively. Other treatments were inconsistently cost-effective. Conclusions: The cost-effectiveness of treatments for medically refractory pediatric epilepsy was not definitive. Consistency in study design and inputs is necessary for future comparison of epilepsy treatment.
P.038 Exploring alternative deep brain stimulation targets for movement disorder in children – a systematic literature review
Authors: AlGethami H , Sulistyo AT , Breitbart S , Fasano A , Ibrahim G , Gorodetsky C
Published: May 2024

Background: Deep Brain Stimulation (DBS) has become increasingly prevalent in the management of paediatric movement disorders, with the globus pallidus interna (GPi) serving as the most utilized target. However, limitations exist, including variable responses in genetic versus acquired forms of movement disorder and structural damage in the GPi would preclude its use as a target. Given these limitations, there is a pressing need to explore alternative targets. We investigated the application of non-GPi targets in paediatrics through a systematic review. Methods: Individual data points were gathered from references identified through a systematic electronic search and analysed descriptively. We included paediatric patients (0-18 years) with movement disorders who underwent non-GPi-DBS. We excluded adults and other indications. Results: Preliminarily, 64 patients were identified from 40 references. Dystonia was the most common movement disorder type, followed by tremor and chorea. The subthalamic nucleus was the frequent DBS target for dystonia, yielding promising outcomes of improvement as measured on the Burke-Fahn-Marsden movement scale ranging from 43% to 95%. The ventral intermediate nucleus was the second most employed target, demonstrating favourable results. Conclusions: Non-pallidal DBS targets hold promise as potentially efficient and safe. However, to further validate their effectiveness and safety, larger multi-centre randomized studies are required.
P.040 Decreased incidence of neuro-autoimmune disorders during COVID-19 pandemic restrictions
Authors: Jaremek A , Chisvin R , Kutcher SA , Webster RJ , Kazoun F , Goldbloom EB , McMillan HJ , Pohl D
Published: May 2024

Background: Infections are hypothesized to trigger certain autoimmune diseases; however, data surrounding incidence trends of pediatric neuro-autoimmune disorders during the COVID-19 pandemic are lacking. Our retrospective study thus assessed the incidence of pre-defined autoimmune disorders diagnosed at the Children’s Hospital of Eastern Ontario in Ottawa, Canada between October 2017 and June 2023. Methods: Inpatient and outpatient charts were queried to identify subjects with neuro-autoimmune disorders or type 1 diabetes (T1D) as a non-neurological autoimmune comparison group. Monthly incidences were calculated and grouped based on three COVID-19 pandemic restriction periods: the pre-restrictions period (October 2017-March 2020), intra-restrictions period (April 2020-June 2022), and post-restrictions period (July 2022-June 2023). Poisson regression models were fit to the incidence data. Results: New diagnoses of neuro-autoimmune disorders and T1D were identified in 86 and 591 subjects, respectively. Incidence of neuro-autoimmune disorders decreased significantly during the intra-pandemic restrictions period when compared to the pre-pandemic period (IRR=0.56, 95% CI: 0.32-0.93, P<0.05). Albeit not statistically significant, the incidence then increased to higher than pre-pandemic levels during the post-restrictions period. T1D showed no significant changes in incidence. Conclusions: Incidence of neuro-autoimmune disorders, but not T1D, decreased during COVID-19 pandemic restrictions, which may be due to reduced transmission of key infectious triggers.
P.041 3 year longitudinal health related quality of life in a spinal muscular atrophy cohort
Authors: Daudu DO , Campbell C , Reilly J , Arocha Perez J
Published: May 2024

Background: Spinal Muscular Atrophy (SMA) is a rare, genetic disorder marked by motor neuron degeneration, causing progressive muscle weakness. SMA significantly impacts patients and their families. This study investigates HRQOL in a longitudinal SMA cohort. Methods: The study used the Canadian Neuromuscular Disease Registry to examine HRQOL in children aged 6-10 years with genetically confirmed SMA. HRQOL was evaluated using the PedsQL™ Measurement Model. This tool is validated in children and adolescents with various health conditions. The PedsQL Neuromuscular Module which has been validated in SMA was also used. Results: Eight participants completed the PedsQL generic and Neuromuscular Module at timepoint 1 (TP1) and 2 (TP2). The mean scores at TP1 were 49.66 (SD=5.05) for the generic PedsQL and 61.06 (SD=18.37) for the Neuromuscular Module. At TP2, mean scores increased to 59.32 (SD=13.08) and 74.86 (SD=9.88), respectively. The overall mean change over the two timepoints was +9.66 (SD=15.16) for the Generic PedQL and +13.80 (SD=23.03) for the Neuromuscular Module. Six participants were on disease modifying treatment. Conclusions: HRQOL scores in SMA patients improved over the study period. The enhancement in HRQOL may indicate the positive impact of diseases modifying treatments of SMA that became available during that time.
P.046 Review of the management of Wernicke encephalopathy in pediatrics
Authors: Bourcier D , Veysey A
Published: May 2024

Background: Wernicke encephalopathy (WE) is a neurological emergency defined by acute encephalopathy, oculomotor dysfunction, and ataxia. Pediatric cases of WE are underdiagnosed despite having a similar incidence to adults. There are no available treatment guidelines for pediatric WE. Prompt treatment with thiamine can prevent devastating consequences. Methods: A rapid review of the literature of the past 20 years with selected relevant older articles was conducted for the research question “How does child and adolescent thiamine therapy management for Wernicke Encephalopathy compare to adult guidelines?” All articles reporting the investigation, management and treatment of Wernicke encephalopathy – both non alcohol related and alcohol-related pediatric cases – were included. Articles not reporting clinical outcomes were excluded. Results: Eleven case studies including one available review article, met the inclusion and exclusion criteria. An algorithm was created for the organization of published reports of the management of WE for children and adolescents. Key considerations were included for the prevention, identification, acute and ongoing management of patients with WE. Conclusions: The recognition of risk factors for thiamine deficiency and symptoms of acute WE should prompt immediate treatment with thiamine – as a routine and safe therapy in the pediatric population.
P.048 Prevalence, type and risk factors of intracranial hemorrhage in term neonates: a systematic review and meta-analysis
Authors: Chisvin R , Datta D , Tu A
Published: May 2024

Background: Intracranial hemorrhage (ICH) in newborns poses a significant challenge to wellbeing and development. In preterm neonates, germinal matrix hemorrhage is most common. In term neonates, prevalence and type of ICH has not been well elucidated. This systematic review aims to assess prevalence, type, and risk factors of ICH in term neonates. Methods: A systematic review was conducted. Inclusion criteria was ICH in neonates born at 37+ weeks gestation. Exclusion criteria was one type of ICH, one risk factor, sample size <20, text not in English, full text not accessible. Eligible studies were evaluated by two authors, data was extracted and analyzed using a predesigned template and MetaXL. Results: A total of 1226 records were initially identified and 20 studies were included in the final analysis. The overall prevalence of ICH was 9.3%. This was subdivided into an asymptomatic subgroup (5.8%) and symptomatic subgroup (29.3%). Analysis showed CT detected ICH most commonly. Extra-axial hemorrhage was most commonly detected (~30%), with subdural more common than extradural hemorrhages. The odds of having an ICH was significantly higher with instrumental delivery (3.75%). Conclusions: This shows that prevalence of ICH is relatively high in symptomatic children. Measured prevalence varies according to the type of modality used for screening.
P.052 Utility of amyotrophic lateral sclerosis functional rating scale (ALSFRS) bulbar subscores for predicting need for gastrostomy tube
Authors: Perera T , Greenfield J , Jewett G
Published: May 2024

Background: We evaluated the utility of the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) in predicting risk of gastrostomy tube (G-tube) insertion in patients with ALS. Methods: We conducted a retrospective study using the Pooled Resource Open-Access ALS Clinical Trials Database. People with ALS, at least two ALSFRS scores, and baseline swallowing subscore >1 were included. G-tube outcome was defined as reaching a swallowing subscore ≤1. Predictors were ALSFRS bulbar subscores (swallowing, speech, salivation). Survival analyses estimated median time to outcome and cumulative probability of outcome within 91 days. Individuals were censored at last ALSFRS score. Results: We included 6,943 participants. Median [95% CI] time to G-tube insertion was 245 [228, 285], 562 [547, 621], and 1,268 [980, 1,926] for baseline swallowing subscores of 2, 3, and 4, respectively. Probability of G-tube insertion was associated with baseline swallowing, speech, and salivation subscores (log-rank test p < 0.0001). For patients who transitioned to a swallowing subscore of 2 or 3, 18.1% [95% CI 16.1, 20.3] and 1.9% [95% CI 1.3, 2.7] required G-tube insertion within 91 days of score transition. Conclusions: ALSFRS bulbar subscores may identify patients at risk of G-tube insertion. Probability of G-tube insertion within 91 days is low if swallowing subscore ≥3.
P.063 Refractory pediatric CIDP converting to full recovery with rituximab
Authors: Khattab FH , Baker SK
Published: May 2024

Background: Chronic inflammatory demyelinating polyradiculoneuropathies (CIDP) is a rare, acquired polyneuropathy, especially in children, affecting the peripheral nervous system. It most commonly presents in a symmetric, proximal and distal, sensorimotor fashion. Immunosuppression and immunomanipulation are treatment modalities. We present a case of a 14 year old male with severe progressive CIDP who became refractory to steroid and IVIg but responded to Rituximab. Methods: Case presentation: A 14-year-old male with a history of asymmetric quadriparesis was diagnosed with CIDP. He had an initial partial response to IVIG and prednisone but then rapidly became refractory to even weekly IVIG and prednisone. Rituximab was therefore started. Results: Within 12 weeks his strength improved from quadriplegia to walker-assisted gait. By 22 weeks he achieved independent ambulation. His JAMAR hand grip increased from 0 to 28 kg. His worst recordable median conduction velocity (CV) improved from a nadir (MRC 0/5) of 14% of normal to 52% at full recovery (MRC 5/5). Conclusions: This case highlights several important clinical points. Dramatic improvement is possible in cases of quadriplegic CIDP. Strength recovery is not linearly related to CV recovery. There appears to be a role for polytherapy.
P.065 Understanding treatment barriers and adherence among people living with amyotrophic lateral sclerosis
Authors: Matte G , Blackburn D , Bolano Del Vecchio D
Published: May 2024

Background: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with only four approved treatments in North America - sodium phenylbutyrate (PB) and ursodoxicoltaurine (TURSO, also known as taurursodiol), riluzole, edaravone, and tofersen. Poor treatment adherence reduces clinical effectiveness which can adversely impact disease progression and mortality rates. Understanding barriers and adherence to treatment in clinical practice is essential to address these issues. Methods: A scoping review was conducted in PubMed, Medline, Embase, and Web of Science. Retained studies were, (1) published in English, (2) included adults with ALS, (3) explored treatment non-adherence and/or identified barriers associated with non-adherence in ALS in real world clinical practice, (4) focused on ≥1 of the four approved ALS medications, and (5) used a measurement of adherence. Observational studies, real-world data, and case reports were included. Quality assessment was performed. Results: The review illustrated several knowledge gaps, including limited data on the incidence of non-adherence to ALS treatment in clinical practice, a lack of understanding regarding barriers to treatment adherence in ALS, and an absence of studies outside of western societies. Conclusions: We demonstrate a dearth of real-world data on treatment adherence in ALS and highlight opportunities for advancing research into this important area.
P.066 A 65 year-old male with subacute asymmetric, proximal more than distal upper extremity weakness with associated paresthesias and pain
Authors: Mesbah-Oskui L , Marais O , Alabkal J , Randhawa N , Mezei MM
Published: May 2024

Background: Neuroborreliosis affects approximately 10-15% of people with untreated Lyme disease and typically declares itself 2-18 weeks after infection. North American neuroborreliosis often manifests with cranial nerve palsy, meningitis, and/or radiculoneuritis. Methods: Here we describe a case of North American neuroborreliosis and also highlight some of the rare manifestations of systemic Lyme disease. A 65-year old male presented with a subacute history of progressive upper extremity weakness, neck pain, and headache. This occurred in the context of a recent tick exposure. Results: MRI of the brachial plexus, serology and CSF studies, and EMG/NCS were consistent with a diagnosis of polyradicular neuroborreliosis. However, whole body imaging identified some concerning features suggestive of lymphoma: specifically a large necrotic mediastinal lymph node and a number of vascular abnormalities. In light of these findings, the differential also included neurolymphomatosis and a PET scan was conducted. Reassuringly, there was no increase in FDG avidity in the distribution of his affected nerves. Moreover, his neurologic symptoms exhibited clinical improvement following treatment of his neuroborreliosis. Conclusions: This case provides an excellent example of the clinical features of neuroborreliosis, but more importantly also highlights some of the rarer potential manifestations, which warrant further investigation.
P.069 Development of a streamlined multi-disciplinary care pathway for compression neuropathies
Authors: Chapman KM , Bristol S , Tang D , Berger M , Bao L , Khayambashi S , Carr A , Little B , Portner B , Kula M
Published: May 2024

Background: Care for patients with compression neuropathies (carpal tunnel syndrome, ulnar neuropathy) is often fragmented, uncoordinated, and slow. Patients go through multiple steps (neurology consultation, nerve testing, ultrasound, splints, injection, surgical opinion, surgery) with waits between each step. We used a Value-Based Health Care (VBHC) model to develop a multidisciplinary clinic with a novel care pathway. Methods: A Shared Care initiative supported the development of an Integrated Practice Unit (IPU). Key multidisciplinary team members were identified. Participants attended a curated three part VBHC workshop. Process mapping enabled identification of efficiencies. Results: 14 team members participated in the workshops. Condition specific outcome measures were identified (Boston CTS measure, 10-point touch, MRC strength and pain scale) and will be collected longitudinally. Criteria and clinical pathways were developed for mild, moderate, and severe carpal tunnel syndrome. Resource materials for patients and providers were developed. Conclusions: A VBHC framework supported development of a novel clinic for compression neuropathy. Responsibility for the full cycle of care rests with the IPU. Systematically tracking functional outcome measures enables quality improvement. By streamlining the patient journey and substantially reducing wait times between steps, the new care pathway reduces complexity and improve outcomes. Evaluation of impact if this new clinical model is ongoing.
P.073 Spontaneous fluctuation of contrast enhancement in adult pilocytic astrocytoma and other low-grade brain tumors
Authors: Rohringer T , Ong SK , Gao AF , Alcaide-Leon P
Published: May 2024

Background: Pilocytic astrocytoma and other circumscribed low-grade brain tumors can exhibit spontaneous enhancement changes despite stable size and clinical status. We aimed to describe this phenomenon in adults. Methods: We performed a retrospective review of our MRI database (2011-2021) to identify cases with enhancement changes in otherwise stable tumors. We searched for reports containing: “pilocytic”, “pilomyxoid”, “RGNT”, “rosette”, “glioneuronal”, “DNET”, and “dysembryoplastic”. Exclusion criteria included WHO grade 3/4 tumors, patients <19 years, equivocal diagnostic findings, and no serial MRIs. We reviewed 238 patients. Results: We identified 12 adult patients with the desired phenomenon: 6 pilocytic astrocytoma, 1 pilomyxoid astrocytoma, 2 rosette-forming glioneuronal tumor, 1 unverified low-grade glioma, and 2 cases without biopsy. Seven were untreated, while five were residual or recurrent tumors. Six showed a pattern of new/increasing and subsequent decreasing/disappearing enhancement over 1-4 years. One exhibited spontaneous regression of enhancement over 1 year. Five showed repeating cycles of increasing and decreasing enhancement over longer monitoring periods of 7-15 years, with mean duration of increasing enhancement prior to decline of 21.4 months (SD 5.9). Conclusions: Spontaneous contrast enhancement fluctuation in adult pilocytic astrocytoma and other circumscribed low-grade brain tumors can occur, and on its own should not be misconstrued as evidence of tumor progression/regression.
P.083 Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept
Authors: Brakel BA , Wang J , Kam J , Huttunen H , Dhaliwal B , McEwen J , Westerberg B , Makarenko S , Akagami R
Published: May 2024

Background: Surgical resection of vestibular schwannoma (VS) is often curative if gross total resection is achieved, however, it is a delicate procedure with high risk to the facial nerve. With retrosigmoid approach for resection, the head is positioned to maximize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding. Methods: Here, we review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusions: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and potentially other neurosurgical procedures.
P.085 Characterizing molecular alterations in glioma growth and progression
Authors: Ye V , Dirks P
Published: May 2024

Background: High grade gliomas (HGG) are incurable, aggressive brain malignances that carry poor prognoses. Significant scientific advances have uncovered many of the features of these diseases; however, it remains unclear how mutations and transcriptional changes drive glioma growth and progression. Methods: We used a Nestin-Cre mouse model in combination with an extrinsic chemical mutagen (N-ethyl-N-nitrosurea, ENU), to model HGG. We combined our mouse model with live animal in vivo magnetic resonance imaging to track tumor growth over time, and sample discrete lesions during premalignant, early stage tumor, and end stage tumor phases. Results: We show that the somatic mutations, copy number changes, and transcriptional profiles of tumors vary depending on the stage of growth, and that the Raf/Ras pathway is key for tumor growth with a recurring Braf mutation occurring in early stage lesions. Gene set enrichment analysis (GSEA) shows that end stage tumors have increased immunogenic/inflammatory activity, and increased signaling through Raf/Ras. Conclusions: The combination of genetic and nongenetic insults results in activating mutations in early lesions, which continue to be biologically active and underlie key differences between early and end stage tumors. Overall, this work sheds light on important differences between early and late stage tumors.
P.108 Rate and clinical utility of early postoperative CT head in adult craniotomy
Authors: Harmsen IE , Fatokun I , Elliott C
Published: May 2024

Background: Postoperative cranial neurosurgical imaging practices are highly variable. We evaluated the rate and utility of early postoperative computed tomography (EPCT, defined as a CT head scan within 24h of surgery) in consecutive adult craniotomies. Methods: We retrospectively reviewed consecutive adult craniotomies at the University of Alberta Hospital over a 45-day period (17/09/2022 to 01/11/2022). Electronic medical records were reviewed to extract data on the rate, timing, and utility of EPCT as well as the rate of neurologic deterioration and repeat surgical intervention. Results: A total of 56 patients (27 female; 55.5 ± 2.1 yrs, range: 19-84 years) were identified. All patients underwent EPCT, including 10/56 (17.9%) on POD0 and 46/56 (82.1%) on POD1. Surgical complications (bleeding, extensive pneumocephalus, edema, ischemia) were identified in 8/56 (14.3%) of the EPCT, of which 6 (10.7%) were reported to have neurologic deterioration and 2 (3.6%) underwent further surgical intervention (hematoma evacuation). Clinical and radiological postoperative changes were highly related (p=5.16e-06), and the rate of EPCT being adverse without neurologic deficit, managed surgically, was 1/56 (1.8%). Conclusions: EPCT is routine practice. Given the low rate (1.8%) of repeat surgical intervention in the absence of neurologic deficit despite abnormal EPCT, omitting EPCT in neurologically intact patients may be warranted.
P.109 Machine learning based approach to improving the prediction of neurological deterioration in mild Degenerative Cervical Myelopathy
Authors: Al-Shawwa A , Craig M , Ost K , Tripathy S , Cadotte D
Published: May 2024

Background: Degenerative cervical myelopathy (DCM) is the most common form of atraumatic spinal cord injury globally, yet clinical guidelines remain unclear on surgical recommendations for patients with mild forms of DCM. This is in part due to limitations in current MR imaging interpretation and complex mechanisms of neurological deterioration. Supervised machine learning (ML) models can help to identify clinical and imaging indicators of deterioration within mild DCM patients. Methods: 127 MRI scans (T2w, Diffusion Tensor Imaging, and Magnetization transfer scans) accompanied by a series of clinical tests underwent a semi-automated analysis to derive quantitative metrics. Random forest classifier, Support Vector Machine, and Logistic Regression models were trained and tested to predict 6-month neurological deterioration within patients. Results: The ML models performed, on average, better than previous studies with a balanced accuracy ranging between 70-75%. “Advanced” imaging metrics such as diffusion tensor imaging and magnetization transfer scans played an important role in improving model accuracy but only when used near the maximally compressed disc level, suggesting that limited yet targetted imaging metrics support ML model performance. Conclusions: The inclusion of specific, targeted imaging and clinical metrics support ML model performance in predicting neurological deterioration within mild DCM patients.
P.135 Automated awake brain mapping with eloquentaid: a novel tool for low-resource settings
Authors: Guo E , Pascual JG , Cua SN , Khu KO , Lama S , Sutherland GR
Published: May 2024

Background: Intraoperative testing for awake craniotomies requires a multidisciplinary team which may not be available in low-resource settings. We explored the creation of an AI tool for automated testing. Methods: We developed a NodeJS application, EloquentAid (https://www.eloquentaid.com/), for language testing automation. The workflow was as follows: users select an image-based naming task and verbally identify the image in English. Then, the application transcribes the response using OpenAI’s Whisper transcription service. Finally, the application evaluates response correctness. Feedback is provided through auditory and color signals. To assess its reliability, we tested the EloquentAid versus a human rater using a 57-item test based on the Boston Naming Test. Participants were neurosurgery and neurology residents from the Philippines. Qualitative surveys were obtained post-test. Results: A total of 798 observations were recorded (N=14). Human-application agreement was 60.52%. Cohen’s kappa was 0.31 (fair agreement). There were no false positive identifications by EloquentAid. Noun-type was felt to affect human error (i.e. “knocker,” “yolk,” “trellis”). Accent and pronunciation were felt to affect EloquentAid errors. Conclusions: EloquentAid is a promising tool to facilitate intraoperative testing and brain mapping using AI for speech recognition and response evaluation. Preliminary data shows fair human-app agreements. Improvements in test items and pronunciation recognition may be made.
P.136 Implementation of BC Children’s Hospital’s intraventricular hemorrhage of prematurity management pathway: a quality improvement analysis
Authors: Elder MW , Weir A , Watson I , Haji F , Singhal A , Tamber M
Published: May 2024

Background: Early placement of a ventricular access device (VAD) may decrease the need for permanent CSF diversion and improve cognitive outcomes in premature infants with intraventricular hemorrhage. In 2019, BC Children’s Hospital implemented a multidisciplinary early intervention pathway for these infants. This study evaluated process and compliance measures related to protocol implementation. Methods: A retrospective quality improvement chart review of enrolled infants was performed. Select measures included time to neurosurgery consult and intervention, compliance with VAD tapping and ultrasound protocols, overall ultrasound resource use, and complications. Results: Sixteen patients were included. Median time to VAD insertion was 6 days (IQR 4-9.5), greater than the 3-day target. Transfer time from peripheral NICUs and access to OR time were found to be important reasons for delay. Patients received a median 92.2% (IQR 85.1-100%) of the ultrasounds required by protocol, with a median of 36.5 (IQR 29-43.25) ultrasounds per patient. VAD tapping was 88.8% (IQR 75.6-94.8%) compliant; most protocol deviations were indicated taps not performed due to technical difficulties. Conclusions: Compliance with the new protocol was satisfactory. Areas for improvement include continued education at peripheral NICU sites to minimize transfer delays, improved access to the OR, and maintenance of technical skills amongst our NICU partners.
P.142 The use of intraoperative magnetic resonance imaging for endoscopic transnasal transsphenoid surgery in children
Authors: Balasubramaniam N , Tewfik M , Shwartz J , Daniel S , McHugh T , Dudley R
Published: May 2024

Background: Sellar and suprasellar pediatric lesions are uncommon. Endoscopic transnasal transphenoidal surgery (ETTS) is the preferred treatment, but early post-op MRI is hindered by sphenoidal packing. This study aims to assess iMRI safety and efficacy in pediatric ETTS cases. Methods: We performed a retrospective review from Jan 01, 2015 to Dec 31, 2022, evaluating use of iMRI. We determined if the goals of the surgery (biopsy, cyst decompression, subtotal resection, gross total resection) were met, and iMRI’s influence on surgery outcomes. We examined patient age, surgery duration, length of stay, histopathology results, surgical complications, post-op MRIs within 1 month, and tumor progression/recurrence. Results: Over eight years, 20 pediatric ETTS procedures, 14 with iMRI, were conducted. Achieving goals in 13 cases, iMRI prompted extra surgery once. Two adenomas progressed, requiring a second surgery, and craniopharyngioma cases had complications, needing further interventions. Hospital stays varied (1-9 days), with a mean surgery duration of 6 hours and 47 minutes. The study underscores iMRI’s potential impact, stressing the necessity for more research in pediatric transsphenoidal surgeries. Conclusions: While intraoperative MRI in pediatric transsphenoidal surgeries may aid goal verification, this small study doesn’t conclusively demonstrate improved outcomes. Complication rates align with non-IMRI procedures, highlighting the need for further research.
P.143 Safety of same-day discharge following incidental durotomy in tubular microdiscectomy: a retrospective cohort study
Authors: Liu E , Saeed S , Coote N , Su J , Toyota P , Newton B , Persad AR , Fourney DR
Published: May 2024

Background: Cerebrospinal fluid (CSF) leak is a common complication of minimally invasive tubular microdiscectomy (MIM). However, it is not known whether patients with CSF leak can be safely discharged home the same day. Methods: This is a retrospective cohort study of patients with incidental durotomy after MIM from January, 2009 to August, 2023. Patient demographic information, surgery information, CSF leak management, and postoperative outcomes were recorded. Results: There were 16 patients (53%) who were admitted to hospital and 14 (47%) patients discharged home the same day post CSF leak. There were no differences in patient demographics between the two groups at baseline. Twenty-nine out of 30 (97%) of the patients had onlay duraplasty, and one (3%) patient was repaired using sutures. The hospitalized group was kept on bed rest overnight or 24 hours. The discharge group was kept on best rest for 2 hours or mobilized immediately after surgery. The average length of admission for the hospitalized group was 2.4 ± 4.0 days. No patients in either group required readmission or revision surgery for CSF leak. Conclusions: Patients with CSF leak post minimally invasive tubular microdiscectomy can be safely discharged home the same day provided that duraplasty or primary repair was performed intraoperatively.
P.148 Consult and kyphoplasty delay impacts on geriatric vertebral compression fracture outcomes
Authors: Surendran V , Shi V , Kwok D , Martinyuk A , Pahuta M , Guha D
Published: May 2024

Background: Vertebral compression fractures (VCF) lead to both considerable morbidity and increased mortality. Kyphoplasty, a minimally invasive surgery, treats VCFs providing significant pain relief, preserving vertebral height, and reducing spinal deformity. Methods: A retrospective cohort study at Hamilton Health Sciences (HHS) was conducted on elderly patients (60 years or older) who underwent kyphoplasty at between 2012 and 2022. The patients had prior hospital admissions under non-spine-related specialties at HHS within two years before their surgery. Primary outcomes were the progression of vertebral height loss and focal kyphotic deformity. Results: The study included 119 patients (52.1% female, mean age 70.71 years). A significant increase in vertebral height loss was observed from diagnosis to pre-kyphoplasty (0.32% change, p < 0.0001) and from diagnosis to post-kyphoplasty (0.24% change, p = 0.015). However, there were no significant correlations between delay times and changes in vertebral height or focal kyphotic deformity. Conclusions: Delays in neurosurgical consultation and kyphoplasty did not significantly affect radiographic outcomes in elderly patients with VCF despite the progression of vertebral height loss. This suggests that while timely patient care is essential, delayed treatment may not adversely affect key radiographic metrics in elderly VCF patients.