To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Background: Cognitive flow has been linked with enhanced performance, career satisfaction, and decreased burnout. However, while elite sport has long trained athletes to enter flow states, the concept has not been adopted strongly in healthcare. Flow has primarily been explored from a unidimensional (cognitive) perspective. The present study sought to understand the experience of flow among surgeons through a multidimensional lens. Methods: Using a constructivist grounded theory methodology, semi-structured interviews were conducted with 19 staff surgeons at the University of Toronto, purposively sampled. Data were coded and analyzed iteratively by three researchers until theoretical saturation was achieved. Results: Although many surgeons had not previously heard of cognitive flow, the phenomenon deeply resonated with most. Participants described different physical, cognitive, emotional, sociocultural, and environmental components that interacted to shape the subjective experience of flow: “I think that there are many different facets of [flow] that don’t always come together all at the same time, you may feel different parts of it… depending on what the kind of case is, who your help is, if you recently had a complication.” (P4) Conclusions: Understanding flow in clinical practice may lead to new avenues for enhancing career satisfaction and promoting physician wellness.
Background: Intravenous Immunoglobulin (IVIg) use for Central Nervous System (CNS) conditions has increased over the last decade. In many CNS disorders, robust evidence for IVIg efficacy is still lacking. Building on the success of the British Columbia (BC) Neuromuscular IVIg utilization initiative, Guidelines for IVIg use in CNS conditions were developed. A provincial screening program was launched in 2023. Methods: For CNS IVIg, requests, diagnosis, dosing, consultation letters and treatment questionnaires were reviewed. Patient management was compared to provincial guidelines. A letter was sent to the ordering physician with the results of the review and treatment recommendations when management differed significantly from guidelines. Review of the first year’s cases was conducted. Results: Over the first 11 months of the program, 79 IVIg renewal requests were reviewed. The most common diagnoses were antibody mediated autoimmune encephalitis, severe drug resistant non-surgical epilepsy and Susac’s syndrome. Recommendations included dose reduction, discontinuation of IVIg, or initiation of alternative therapies for many of the requests. Conclusions: IVIg may be effective in the management of some CNS inflammatory conditions. A physician-led utilization program in BC with targeted education to ordering physicians promotes best practice. Review of year one data will inform a quality improvement cycle to optimize the guidelines.
Background: Near-infrared spectroscopy regional cerebral oxygen saturation (rSO2) has gained interest as a raw parameter and as a basis for measuring cerebrovascular reactivity (CVR). This study aimed to identify threshold values of rSO2 and rSO2 based CVR at which outcomes worsened following traumatic brain injury (TBI). Methods: A retrospective multi-institutional cohort study was performed. The cerebral oxygen indices, COx (using rSO2 and cerebral perfusion pressure) as well as COx_a (using rSO2 and arterial blood pressure) were calculated for each patient. 2x2 tables were created grouping patients by alive/dead and favorable/unfavorable outcomes at various thresholds of COx and COx_a as well as rSO2 itself. Chi-square values were calculated to identify the most discriminative significant threshold. Results: In the cohort of 129 patients rSO2 did not have any statistically significant threshold value. For COx and COx_a, an optimal threshold value of 0.2 was identified for both survival and favorable outcomes with values above this associated with worse outcomes. Conclusions: In this study, raw rSO2was found to contain no significant prognostic information. However, rSO2 based indices of CVR, were found to have a uniform threshold of 0.2, above which clinical outcomes worsened. This study lays the groundwork to transition to less invasive means of continuously measuring CVR.
Background: Sedation in PICU masks physical exam findings, leading to diagnostic challenges. In adult models, electroencephalography can evaluate the brain’s response to sedation using feedforward connectivity and anteriorization of alpha hubs, proving useful for prognostication. Feasibility of model translation into pediatric population was assessed, with the hypothesis that the same markers of adaptive reconfiguration would correlate with a higher potential for recovering consciousness. Methods: Electroencephalograms from children undergoing sedation were analyzed for strength and direction of functional connectivity using the weighted and directed phase lag index. Target population was refined with an iterative inclusion criteria. We examined relationships between hub location reconfiguration, directed phase lag index, baseline Glasgow Coma Scale, and 3-month post-treatment Glasgow Outcome Scale-Extended. Results: Evaluation of 14 subjects showed promise in children aged 5-18 undergoing sedation with midazolam, dexmedetomidine, and propofol. Further analysis of five subjects revealed a correlation between adaptive reconfiguration during anesthesia and both higher baseline Glasgow Coma Scale and Glasgow Outcome Scale-Extended scores post-treatment. Conclusions: The findings indicate that the functional brain network connectivity model may have diagnostic and prognostic potential regarding children’s consciousness levels. While the initial data is promising, further analysis of six additional cases is pending and deemed essential to thoroughly evaluate the model’s efficacy.
This article maps the shared legal anatomy of climate and environmental lawsuits, in which plaintiffs claim protection for future generations before domestic or international courts. By closely analyzing the litigation strategies of plaintiffs and the inquiry of courts, the article argues that these proceedings revolve around structurally similar legal standards across domestic and international jurisdictions, which correspond to five normative requirements flowing from the rule of law: namely, respect for human rights, certain quality of law requirements, prohibition of arbitrary exercise of governmental powers, non-discrimination, and access to justice. The cross-jurisdictional analysis shows that courts appear to be increasingly willing to protect future generations against arbitrary treatment by present-day decision makers. The article appraises whether such an intergenerationally sensitive reinterpretation of the rule of law could help to change the short-termist paradigm of environmental and climate law.
Background: Considering regional and temporal trends, we sought to explore the incidence of primary malignant brain tumours in Newfoundland and Labrador. Methods: We reviewed all primary, malignant brain tumour cases from 2015-2022 confirmed by St. John’s Health Sciences Centre pathology reports. Incidence rates were standardized using the 2011 Canadian standard population. Results: We included 362 cases. The average annual age-standardized incidence rate of primary, malignant brain tumours per 100,000 was 7.0 (95% CI: 6.3-7.7), lower than the national average (7.93; 95% CI: 7.78-8.08). The incidence of glioblastoma (5.1; 95% CI: 4.5-5.7) was significantly higher than the national average (4.05; 95% CI: 3.95-4.16). Temporal trends revealed that oligodendroglioma incidence spiked from 0.5 (95% CI: 0.2-0.7) in 2015-2019 to 1.5 (95% CI: 0.4-2.6) in 2020 before returning to baseline in 2022. Regional trends indicated a lower incidence of malignant tumours in Labrador-Grenfell (5.1; 95% CI: 2.5-7.6), compared to 6.9 (95% CI: 6.2-7.6) averaged elsewhere. Conclusions: Higher rates of glioblastoma in Newfoundland and Labrador could have a genetic or multi-factorial cause. The increased occurrence of oligodendroglioma during the COVID-19 pandemic necessitates broader investigation, potentially linked to delays in patient care during this period. Regional trends could suggest less access to care in rural populations and underestimated incidence.
Background: In early-stage transsylvian aneurysm surgery, achieving brain relaxation is crucial for the safe exposure of aneurysms; however, in cases of tight, hemorrhagic brains, ventricular drainage is often required. Although Paine/Samson initially proposed a ventricular access point in the frontal horn of the lateral ventricle, and numerous points and techniques have been described since, their consistency and success rates have not undergone rigorous evaluation through comparative cadaveric anatomical studies. Methods: We injected 2 cc agar-agar solutions with distinct colors into the lateral ventricles of twelve cadaveric brains, utilizing four described points, followed by refrigeration at 4°C for one hour for each injection. Next, the brains were sectioned in the coronal plane at 2 cm intervals for evaluation. We assessed the efficacy of the injections in reaching the ventricles and measured the ventricular dimensions, in addition to calculating the Evans’ index for each brain. Results: Injections at Paine/Samson’s point achieved a 100% success rate, followed by Hyunn’s point with a 91.6% success rate. The success rates at Temporal point and Park point were 83.3% and 58.3%, respectively. Conclusions: We emphasize the significance of direct ventricle puncture technique and our findings indicate that the classical Paine/Samson point is the most reliable among the evaluated methods.
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.
Background: Pineal region tumors are a heterogenous group of pathologies often symptomatic due to occlusive hydrocephalus leading to elevated intracranial pressure (ICP). High ICP may not always be associated with clinical signs. A non-invasive technique for assessment of ICP is measuring the optic nerve sheath diameter (ONSD). The goal of this study was to determine the utility of preoperative and postoperative ONSD measurements for assessment of elevated ICP in children with pineal region tumors. Methods: Retrospective data analysis was performed in patients operated for pineal region tumors at our tertiary care center between 2003 and 2022. Preoperative and postoperative MRI scans were reviewed. Clinical data and ONSD at multiple time points were analyzed and correlated. Results: Thirty-four patients with forty operative cases met the inclusion criteria. Hydrocephalus was seen in 80% of patients preoperatively (n=32/40). Presence of hydrocephalus was associated with significantly elevated ONSD preoperatively (p=0.006) and postoperatively (p=0.017). There was significant decrease in ONSD immediately postoperatively (p<0.001), at 3 months (p<0.001) and 12 months (p<0.001). In patients without hydrocephalus, no significant changes in ONSD were observed (p=0.369). Conclusions: ONSD is a useful adjunct for the identification of high ICP preoperatively and evaluation of treatment response postoperatively in patients presenting with pineal region tumors.
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.
Background: Prolonged length of stay (LOS) after elective spine surgery increases patients’ risk for in-hospital complications and contributes significantly to healthcare costs. Here we explored the role of pain control and other perioperative factors on LOS. Methods: Consecutive adult patients undergoing elective spine surgery were enrolled. The primary outcome was in-hospital LOS following surgery. The primary independent variable was poor pain control on postoperative day 1 (POD1). Univariable analyses followed by multivariable regression analysis were used to investigate the relationship between poor pain control and LOS. Results: 1305 patients were enrolled. Mean LOS was 4.38 days. Incidence of poor pain control was 56.9%. Multivariable analysis revealed poor POD1 pain control was significantly associated with increased LOS (p=0.03), after adjusting for other significant predictors of increased LOS including perioperative hemodynamic instability (p=0.001), perioperative blood transfusion (p=0.000), delirium (p=0.000), POD1 morphine equivalent dose (p=0.000), urinary tract infection (p=0.000), urinary retention (p=0.003), surgical site infection (p=0.000), wound complication (p=0.000), neurologic deterioration (p=0.000), surgical levels (p=0.016), operative time (p=0.007), ASA score (p=0.000), preoperative disability score (p=0.001). Conclusions: Poor pain control on POD1 was an independent predictor of increased LOS after elective spine surgery, highlighting the importance of a proactive approach to addressing pain in the immediate postoperative period.
Background: After a transient ischemic attack (TIA) or minor stroke, the long-term risk of subsequent stroke is uncertain. Methods: Electronic databases were searched for observational studies reporting subsequent stroke during a minimum follow-up of 1 year in patients with TIA or minor stroke. Unpublished data on number of stroke events and exact person-time at risk contributed by all patients during discrete time intervals of follow-up were requested from the authors of included studies. This information was used to calculate the incidence of stroke in individual studies, and results across studies were pooled using random-effects meta-analysis. Results: Fifteen independent cohorts involving 129794 patients were included in the analysis. The pooled incidence rate of subsequent stroke per 100 person-years was 6.4 events in the first year and 2.0 events in the second through tenth years, with cumulative incidences of 14% at 5 years and 21% at 10 years. Based on 10 studies with information available on fatal stroke, the pooled case fatality rate of subsequent stroke was 9.5% (95% CI, 5.9 – 13.8). Conclusions: One in five patients is expected to experience a subsequent stroke within 10 years after a TIA or minor stroke, with every tenth patient expected to die from their subsequent stroke.
Background: Neurodegeneration with Brain Iron Accumulation (NBIA) is a heterogenous group of disorders with the common theme of iron accumulation in the basal ganglia. These disorders typically present in childhood with progressive neurodegeneration and neuropsychiatric symptoms. Caring for an individual with NBIAs is intensive, however it is unknown what factors impact caregiver well-being and quality of life. Methods: Common themes were obtained via literature review of quality of life surveys in children with neurological and chronic illnesses. Five domains were addressed: Diagnosis, Communication, Symptom Management, Clinical Experience and Resources/Support. The survey was approved by the Family Advisory Committee at the CHEO Research Institute and the CHEO REB. The survey was distributed via the Rare Connect Platform to Canadian caregivers. Results: Survey responses are being analyzed and will be presented at the CNSF. Within each domain, Likert scales will be analyzed. Domains will be ranked according to the caregiver responses. Conclusions: Results of this survey will assist in developing care management guidelines, resources for families and help with future advocacy for patients and families affected by NBIAs. The results will also help guide future NBIA Canada Family Conferences.
Background: Charcot Marie Tooth disease is a polygenic disorder with cannonical features of distal amyotrophy, acrohypesthesia, and tight tendoachilles of either axonal (type 2) or demeylinating (type 1) varieties. Type 1 CMT patients are required to possess conduction slowing of a sufficient degree to qualify as demyelinating. Presented is a middle-aged man with an unremarkable neurologic exam and normal electrophysiology. Methods: Standard electrophysiological techniques were employed to obtain the nerve conduction data (Natus Nicolet EDX AT2; Middleton, WI, USA). Repeated next generation sequencing and deletion/duplication analyses were performed. Results: The nerve conduction studies showed no evidence of demyelination in the upper or lower extremeties. The duplication error was confirmed with repeat testing. The heterozygous PMP22 gene duplication encompassed the entire coding sequence involving exons 1-5. Conclusions: CMT1A accounts for the vast majority of dysmyelinating hereditary neuropathies. Phenotypic variability is well described. Presentations include (a) classic conduction slowing, (b) intermediate slowing, (c) conduction block, (d) HNPP-like, (e) absent CMAPs, and (f) normal NCSs in young infants. This is the first case of a neurologically intact adult with CMT1A. Cryptogenic genetic modifier-effect(s) are posited as a possible explanation of the lack of penetrance. Identifying the nature of this modification may prove instructive for future therapies.
Pulmonary atresia with intact ventricular septum and critical pulmonary stenosis usually have to undergo treatment in the neonatal period. Compared to traditional surgical intervention, catheter-based cardiac interventions may achieve similar or superior outcomes for neonates with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, there is limited literature on anaesthesia techniques, challenges, and risks associated with cardiac catheterisation in this population.
Methods:
This article retrospectively analysed the clinical data of pulmonary atresia with intact ventricular septum and critical pulmonary stenosis neonates who were treated with interventional cardiac catheterisation in our hospital from January 2015 to October 2022. Clinical outcomes considered were haemodynamic or pulse oxygen saturation instability, vasoactive requirements, prolonged intubation (>24 h postoperatively), and cardiovascular adverse events.
Results:
A total of 63 patients met the inclusion criteria. All patients survived the intervention. Among the patients with critical pulmonary stenosis, 40 successfully received percutaneous balloon pulmonary valvuloplasty, while three patients received ductal stenting due to moderate right ventricular dysplasia at the same time. For patients with pulmonary atresia with intact ventricular septum, 17 of the 23 patients successfully underwent percutaneous pulmonary valve perforation and percutaneous balloon pulmonary valvuloplasty. Of these, five patients underwent ductal stenting due to unstable pulmonary blood flow. Three patients only underwent ductal stenting. In addition, three patients received hybrid therapy.
Conclusions:
There are various clinical techniques and risk challenges in the interventional cardiac catheterisation of neonatal pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, by mastering the physiological and pathophysiological characteristics of the disease, adequately preparing for the perioperative period, and predicting the procedure process and potential complications, anaesthesia and surgical risks can be effectively managed.
Background: Gender disparities persist in neurosurgery, unfortunately impacting career progression for women. Understanding these challenges is vital for fostering inclusivity. Methods: An international survey designed using a physician wellness framework was sent to neurosurgeons between June 2021 and November 2021. Univariate analysis (Kruskal-Wallis Test) was performed to assess various aspects of perceived career progression as a function of gender. Results: Of the total 537 respondents (64% neurosurgeons, 6% fellows, and 30% residents), 69% identified as male, 29% as female, and 2% as other. Compared to their male colleagues, female neurosurgeons expressed greater desire to advance in their career (p<0.05) and to leave their home country in the interest of job prospects (p<0.05). Despite these aspirations, female neurosurgeons reported that they did not have available career advancement opportunities (p<0.05), that the culture in their country inhibited their career advancement (p<0.05), and that they felt subject to harassment at their workplace (p<0.05). Conclusions: Our survey highlights significant gender-related obstacles in neurosurgical career advancement. Female neurosurgeons express strong career aspirations but face barriers such as limited opportunities, cultural impediments, and harassment. Addressing these challenges is crucial for achieving gender equity in neurosurgery.
Background: In the Phase 3 RAISE study (NCT04115293), zilucoplan significantly improved MG-specific outcomes in patients with acetylcholine receptor autoantibody-positive generalised MG. After the first 12 weeks of the open-label extension study, RAISE-XT (NCT04225871), corticosteroid dose could be changed per the investigator’s discretion. We evaluate changes in corticosteroid dose during treatment with zilucoplan in RAISE-XT. Methods: In RAISE-XT, adults who completed the Phase 2 or RAISE studies (N=200) self-administered daily subcutaneous zilucoplan 0.3mg/kg, either continuing with zilucoplan or switching from placebo. Primary outcome was incidence of treatment-emergent adverse events (TEAEs). We assessed (post-hoc) the proportion of patients who discontinued/reduced or increased corticosteroid dose relative to double-blind baseline up to Week 60. Results: At Week 60, 30% (n=18/60) and 22% (n=12/54) of patients receiving corticosteroids in the zilucoplan and placebo-switch groups, respectively, reduced/discontinued corticosteroids (mean dose reductions: 14mg and 16mg; mean [SD] CFB in MG-ADL scores: -5.00 [3.96] and -5.67 [6.89]. 12% (n=7/60) and 7% (n=4/54) of patients in the zilucoplan and placebo-switch groups, respectively, increased corticosteroid dose (~12mg mean increase in both groups). TEAEs occurred in 188 (94.0%) patients (data cut-off: 08 September 2022). Conclusions: While receiving zilucoplan, discontinuation or dose reduction in concomitant corticosteroids was possible with maintained efficacy.
Background: OSCE-GPT (https://learnmedicine.ca/) is an AI-based app that integrates history, physical exam, and relevant components for case guidance across medical disciplines to help trainees improve clinical skills. With global users across 60+ countries, this preliminary quality improvement study gathers user feedback on neurology and otolaryngology cases. Methods: A survey was distributed to users at the University of Ottawa and Cumming School of Medicine. Participants provided insights on the app’s use, perceived benefits, and suggested improvements. Results: Using 5-point Likert scales, 13 respondents, 9 of which evaluated an otolaryngology case, rated the overall usefulness of the learning tool 4.57± 0.51 (1=very poor, 5=very good), with a score of 4.00±0.65 relative to other teaching methods, such as didactic lectures or grand rounds (1=much worse, 5=much better). Users noted realistic interactions and self-paced learning as beneficial factors. Areas for improvement included a more fluid transition between physical exams and history, geographic variations in cases, and the addition of elements such as non-verbal patient cues or emotional. Conclusions: This study demonstrates utility of OSCE-GPT for medical trainees, particularly for otolaryngology and neurology cases. As cases continue to be added, feedback will be implemented to further improve user experience.
Background: Primary angiitis of the central nervous system (PACNS) is a rare inflammatory condition affecting the parenchymal and leptomeningeal vessels of the CNS. PACNS presenting as a solitary mass lesion (ML-PACNS) constitutes a rare subtype of this pathology. Herein we present the first case reported in Canada of ML-PACNS, presenting with clinical and radiographic findings consistent with a high grade glial neoplasm, as well as a review of the literature on ML-PACNS. Methods: Review of the literature from 1987-2023 was conducted using PubMed to identify features of ML-PACNS and possible treatment paradigms. Results: A number of case reports of ML-PACNS were identified, as well as 6 retrospective analyses of a total of 67 patients. Features such as faster rate of symptom onset, and investigations such as MRI vessel-wall imaging and MR spectroscopy were suggested for identification of ML-PACNS. Treatment was highly variable, but followed guidelines for other neuroinflammatory disorders. Conclusions: Preoperative differentiation between ML-PACNS and CNS neoplasms is difficult due to their similar clinical and radiographic features. However, making this distinction is crucial as PACNS mass lesions can regress entirely with immunosuppressive therapy, potentially obviating the requirement for surgical intervention. Beyond diagnostics, further research is required to establish and validate a treatment paradigm.
Background: Adults with congenital heart disease (ACHD) are at risk for stroke and dementia. We report baseline and Year 1 results from an ongoing study assessing brain health in people with moderate- and great-complexity ACHD. Methods: Participants aged ≥18 undergo baseline and Year-3 brain MRI/MRA and annual cognitive assessment (MoCA, NIH Toolbox-Cognitive Battery (NIH-TB)). Results: Of 93 participants to date, 79 (85%) have completed Year 1 follow-up. At baseline, the great-complexity group had lower MoCA (26.32 vs. 27.38; p=0.04) and NIH-TB scores (total composite 45.63 vs. 52.80; p=0.002) than the moderate-complexity group. Year-1 testing showed numerical improvements across cognitive batteries in both groups. More participants with great-complexity ACHD had white matter hyperintensities (WMH; 72% vs. 55%; p=0.21) and cerebral microbleeds (CMBs; 72% vs. 54%; p=0.17) on baseline neuroimaging, but differences were not significant. Conclusions: Baseline neuroimaging shows a greater-than-expected burden for age of CMB and WMH in the context of previous cardiac surgery. Baseline cognitive performance was worse with great-complexity ACHD. Improved cognitive battery performance across both subgroups at Year-1 suggests a practice effect. Repeat neuroimaging will be performed in Year-3 and cognitive performance is reassessed annually.