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.

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.

Background: Pituitary adenomas are common and often require complex multidisciplinary care with multiple specialists. This may result in a health care system that is challenging for patients to navigate. Audits of care at our institution revealed opportunities for improvement to better align care with patients’ needs. Methods: A quality improvement initiative that incorporated a patient advisory committee of patients who had received treatment for pituitary adenoma at our center and their family members was used to help identify opportunities for improvement. The patient-identified gaps in care included the need to coordinate and minimize appointments and the desire for better communication and education. Based on this information, changes were implemented to the pituitary program, including increasing access to the multidisciplinary clinic and developing a standardized and centralized triage process. Results: A pre and post-intervention analysis consisting of retrospective chart reviews revealed that these changes had an impact on wait times for first assessment, and a significant shift in location of this first visit – with a larger proportion of patients being seen in the multidisciplinary clinic after intervention. Conclusions: We demonstrate that patient involvement, beyond individual patient-physician interactions, can lead to meaningful and observable changes, and can improve the quality of care for pituitary adenoma.

Background: Hirayama Disease (HD) is a rare disorder consisting of insidious onset of unilateral weakness and atrophy of the forearm and intrinsic hand muscles. Vein of Galen aneurysmal malformations (VGAMs) are rare congenital cerebral vascular malformations, consisting of high-flow arteriovenous shunting between a persistent median prosencephalic vein and arterial feeders. Methods: 14 years old boy known for VGAM presented with left-sided HD. His cervical MRI revealed enlarged epidural with anterior, left-ward displacement of the posterior dura and spinal cord. He underwent surgical treatment by laminotomies, along with tenting of an autologous duroplasty to the overlying laminae. Results: We decided to combine epidural venous plexus coagulation with posterior duraplasty and dural fixation using tenting suture which led to a favorable clinical outcome has not been previously proposed in the literature.

We hypothesize that in this context, an abnormal vasculature could also predispose to posterior epidural venous plexus engorgement, anterior dural displacement in cervical flexion, and microvascular changes in the anterior spinal arterial circulation, leading to the progressive anterior horn cell ischemia that lead to the clinical phenotype of HD. Conclusions: The association between HD and VGAM in this patient may provide clues with regard to the pathophysiology of HD.

Background: Current literature provides little consensus on universal guidelines for first-line treatment of chronic subdural hematomas (cSDH). However, administration of local tissue plasminogen activator (tPA) may enhance the traditional method of twist drill drainage (TDD). The study aims to explore the efficacy of TDD with and without tPA, at achieving clinically relevant drainage (200mL) and reducing recurrence of cSDH. Methods: A retrospective review of patients (N=34) with cSDH is presented. Patients who received TDD with tPA (n=17) were identified and matched, based primarily on age and hematoma volume, to a control group (n=17), TDD without tPA. Variables of interest include initial hematoma volume, volume drained, length of stay, and recurrence rates. Descriptive analysis was run. Results: Average age for patients was 74.6 with 76% male. Mean drainage volumes for the tPA cohort was 381.6mL and TDD without tPA cohort was 151.3mL. The addition of tPA resulted in drainage volumes nearly double (1.9x) the clinically relevant amount and had low recurrence rates (12.5%). TDD without tPA failed to result in clinically relevant drainage and had a recurrence rate of 52.9%. Average length of stay differed by two days (9.71 tPA; 7.71 control). Conclusions: TDD with tPA was effective at treating cSDH in our population.

Background: Ventriculoperitoneal (VP) shunt failures in adult patients are common and subject patients to multiple surgeries and a decreased quality of life. A prospective cohort Shunt Outcomes Quality Improvement (ShOut-QI) initiative was implemented to reduce shunt failure incidence through neuronavigation-assisted proximal catheter insertion and laparoscopy-guided distal catheter anchoring over the liver dome to drain CSF away from the omentum. Methods: “Pre-ShOut” and “Post-ShOut” groups of patients included those with and without neuronavigation/laparoscopy, respectively for insertion of a new VP shunt. The primary outcome was shunt failure which was defined as any return to surgery for shunt revision as determined with a standardized clinical and radiology follow-up protocol. Results: 244 patients (97 Pre-ShOut, 147 Post-ShOut), mean age 73 years, were enrolled over a 7-year interval and observed for a mean duration of 4 years after shunt insertion. Neuronavigation improved proximal catheter placement accuracy by 20% (p<.001), and shunt failure occurred in 57% vs 23% in the Pre-ShOut and Post-ShOut groups, respectively (p=.008), representing a 53% relative risk reduction in the incidence of shunt failure. Conclusions: Adult shunt failure incidence may be significantly reduced by improving the accuracy of proximal catheter placement with neuronavigation and reducing the risk of distal catheter failure with laparoscopic-guided placement.

Background: To describe preliminary results of a multi-center, randomized, blinded, placebo-controlled, pilot trial of shunt surgery in idiopathic normal pressure hydrocephalus (iNPH). Methods: Five sites of the Adult Hydrocephalus Clinical Research Network (AHCRN) randomized 18 patients scheduled for ventriculoperitoneal shunting based on CSF-drainage response. Patients were randomized to a Codman® Certas® Plus valve with SiphonGuard at either setting 4 (Active, N=9) or setting 8/”virtual off” (Placebo, N=9). Patients and assessors were blinded to the shunt setting. Outcomes included 10-meter gait velocity, cognitive function, and bladder activity scores. The prespecified primary analysis compared changes in 4-month gait velocity in the Active versus Placebo groups. Placebo-set shunts were then blindly adjusted to the active setting and all patients underwent 8 and 12-month post-surgical assessment. Results: At 4-months, gait velocity increased by 0.28±0.28m/s in the Active Group and 0.04±0.17m/s in the Placebo Group (p=0.071). Overactive Bladder (OAB-q) scores significantly improved in the Active versus Placebo groups (p=0.007). At 8 months, Placebo gait velocity increased by 0.36±0.27m/s and was comparable to the Active Group (0.40±0.20m/s; p=0.56). Conclusions: This AHCRN study shows a trend suggesting gait velocity improves more at an Active shunt setting than a Placebo shunt setting and demonstrates the feasibility of a placebo-controlled trial in iNPH.

Background: Cranial reconstruction is a common consequence of neurosurgical disease and intervention following craniectomy, trauma, infection, congenital defects, or neoplasm. Most commonly, Computer Aided Design-Computer Aided Manufacturing (CAD-CAM) technology is utilized in cases where autologous bone cannot be used. These patient-specific implants provide excellent cosmesis, however individual costs range from $800-15,000, making routine use challenging in the current Canadian health care environment. Here we present a novel method using desktop 3D printers to manufacture patient-specific molds for intraoperative reconstruction of various cranial defects. Methods: Our first patient presented following two separate traumas requiring decompressive craniectomy and subsequent posterior fossa decompression without interval cranioplasty. The second patient required reconstruction during resection of intraosseous meningioma. Both cases were performed using a titanium-mesh/poly-methyl-methacrylate (Ti-PMMA) construct draped over the mold. The third case, cranioplasty following decompressive craniectomy outside the country, was performed using a “two piece” mold and PMMA was casted into the mold and allowed to harden. Results: Patients reported satisfaction with cosmesis, without adverse outcomes. Cost per case was $50-100, representing an estimated cost savings of $685,000 per year in Canada. Conclusions: Given excellent outcomes in addition to cost effectiveness, this case series provides evidence for use of this alternate technique with similar patient outcomes.

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.

Background: Tubular retractors are FDA approved and in the Neurosurgical marketplace, but adaptation has been hampered by lack of evidence showing superiority over traditional retractors when performing subcortical surgery. This study examines brain injury associated with traditional brain retractors versus tubular retractors. Methods: Nine porcine models underwent a simulated neurosurgical operation. Retractors were inserted for four hours after which the porcine model was euthanized. The en-bloc extracted porcine brain was fixed in 10% formalin, paraffin embedded, sectioned at 4 um and stained with hematoxylin and eosin (H&E) using standard laboratory protocols. Computer algorithms were generated to calculate areas of cerebral edema and hemorrhage adjacent to retractor surfaces. Results: Using a two-tailed t-test with a significance level of 0.05, traditional brain retractors were associated with statistically significant greater areas of cerebral edema when compared to tubular retractors (17.36 um2 vs. 12.42 um2; p = 0.0038). There was no statistically significant difference in mean areas of hemorrhage between traditional brain retractors and tubular retractors (3.43 um2 vs 3.60 um2; p = 0.8297). Conclusions: Tubular retractors are associated with significantly less edema in surrounding brain than traditional retractors. On histopathological merits, this study supports the application of tubular retractors over traditional retractors.

Background: Exploring current trends in career outcomes can guide further expansion and diversity in neurosurgery demographics, as well as inform medical trainees of qualifications required for a career in neurosurgery. This study therefore aims to explore temporal trends and gender distribution in training, teaching, and leadership positions among currently practicing neurosurgeons. Methods: A list of practicing Canadian neurosurgeons and their certification year, degrees, fellowships, and teaching positions was created using publicly available information and phone/email confirmation by surgeons. Results: We identified 297 neurosurgeons currently practicing in Canada (F=32, M=265). There was a significant trend towards a greater number of neurosurgical staff having at least one advanced degree or fellowship over time (p=0.0012, p=0.0048 respectively), with no significant difference between proportions of males and females. Within academia, women represent 33% of adjunct professors, 8% of associate professors, and 15.2% of full professors. Two neurosurgical departments in Canada are led by women. Conclusions: Literature shows there is an underrepresentation of women in neurosurgery, particularly in higher-ranking teaching and leadership positions, yet our results suggest there is no significant differences in qualifications between males and females. Further exploration is needed to identify reasons underlying these trends and propose solutions to promote growth in the field.

Background: Adults with obstructive hydrocephalus often present with cognitive and/or gait dysfunction in addition to symptoms of raised ICP. We previously reported improvement of cognitive and gait function 3 months following primary adult ETV. This abstract presents long-term results in this group. Methods: Obstructive hydrocephalus was identified based on tri-ventriculomegaly on CT and/or MRI. Gait velocity (10 m timed gait) and cognitive function (Montreal Cognitive Assessment [MoCA]) were measured at two timepoints: pre-ETV and ≥9 months post-ETV. Results: Sixteen adults underwent primary ETV and completed a long-term assessment. Mean age was 60 years and 10 (63%) were male. Etiology: 10 (62.5%) congenital and 6 (37.5%) acquired. Mean long-term follow-up time for cognitive and gait assessments was 14.4 and 13.7 months, respectively. The long-term MoCA within patient median change was +2 points (n= 15; p = 0.007). Group medians were 23/30 (pre-ETV) and 26/30 (post-ETV). The long-term gait velocity within patient median change was +0.4 m/s (n= 12; p < 0.001). Group medians were 0.7 m/s (pre-ETV) and 1.3 m/s (post-ETV). Conclusions: ETV in adults with obstructive hydrocephalus results in long-term improvement of cognition and gait velocity when assessed ≥9 months post-ETV. Larger cohorts will determine the generalizability of these results. Hydrocephalus Association supported project.

Background: In addition to symptoms of raised ICP, adults with obstructive hydrocephalus often present with cognitive dysfunction. We previously reported the improvement of global cognition at 3 and 12 months following primary adult ETV using the Montreal Cognitive Assessment (MoCA). This abstract presents multidomain cognitive testing using the RBANS. Methods: Obstructive hydrocephalus was identified based on tri-ventriculomegaly on MRI findings with a site of obstruction. Cognitive function was measured using the RBANS and MoCA at two timepoints: pre-ETV and post-ETV. Within patient analysis was conducted using the Wilcoxon Signed Rank Test. Results: Nine adults underwent ETV, 7 primary and 2 secondary (ETV after shunt malfunction), and completed follow-up assessment. Mean age was 33 years old and 7 (78%) were female. Etiology: 3 (33%) congenital and 6 (67%) acquired. Mean follow-up time was 4.5 months. The RBANS total scaled score, attention, and delayed memory index scores were significantly improved post-ETV (p < 0.05). Immediate memory, language, and visuospatial index scores were not significantly different. Secondary analysis shows that picture naming and figure recall subtests were significantly improved. MoCA total scores were not significantly different. Conclusions: ETV in adults with obstructive hydrocephalus results in improvements in global cognition, attention, and delayed memory on RBANS testing.

Background: Performance Heatmaps were designed to visualize the spatial distribution of performance metrics during resection of complex tumors. This novel methodology provides experts (neurosurgeons) and trainees (residents and medical students) with visual feedback on their neurosurgical performance during operative procedures. Methods: Neurosurgeons (NS), senior residents (SR), junior residents (JR) and medical students (MS) performed resection of a complex tumor on the NeuroVR simulation platform. Metrics including time spent, force applied, and tumor volume removed were used to create Performance Heatmaps for each group. Results: During complex operative procedures, greater expertise correlated increased time spent in critical areas (NS = 121.0 s, SR = 103.0 s, JR = 86.1 s, MS = 84.9 s), increased force application (NS = 387 N, SR = 317 N, JR = 340 N, MS = 304 N), and increased tumor removal (NS = .096 cc, SR = .081 cc, JR = .074 cc, MS = .069 cc). Conclusions: Performance Heatmaps further our understanding of neurosurgical expertise by identifying key differences between experts (neurosurgeons) and trainees (residents and medical students). With the adoption of competency-based curricula, intuitive feedback tools will prove essential for trainees seeking surgical mastery.

Background: Timely access to neurosurgeons for clinical advice is limited depending on region and other social factors. An eConsult service providing access to neurosurgeons in Ontario, Canada may influence primary care provider (PCP) course of action and referral behaviours. Methods: The Champlain BASE (Building Access to Specialist Care via eConsult) service allows PCPs to access specialist care in lieu of traditional face-to-face referrals. We conducted a cross-sectional study of eConsult cases submitted to neurosurgeons by PCPs between Jan 1, 2017 and Dec 31, 2018. Usage data and PCP responses to a mandatory closeout survey were analyzed. Results: A total of 432 eConsults were submitted. Specialist median response time was 2.29 days with 86.8% of responses occurring within 7 days. PCPs received a new or additional course of action in 53% of cases. An unnecessary face-to-face referral was avoided in 57% of all eConsults, and 50% of cases where the PCP initially contemplated requesting a referral. Over 86% of cases were rated at least 4 out of 5 in value for PCPs and their patients. Conclusions: The use of eConsult improves access to neurosurgeons by providing timely, highly-rated practice-changing clinical advice while reducing the need for patients to attend face-to-face office visits.

Background: Canada has a universal health care system while the United States utilizes a combined public and private payer system. The purpose of this study is to investigate whether there are differences in clinical outcomes between those surgically treated for spinal stenosis in Canada as compared to the United States. Methods: Surgical lumbar spinal stenosis patients treated in Canada that were enrolled in the Canadian Spine Outcome Research Network (CSORN) prospective multicenter registry were compared with the surgical cohort enrolled in the Spine Patients Outcome Research Trial (SPORT) study. Spine-related patient reported outcomes (PROs) were compared at 3 months and 1 year post-operatively. Results: The CSORN cohort consisted of 432 patients and the SPORT cohort was made up of 278 patients. The CSORN cohort had a higher proportion of patients with a symptom duration greater than 6 months (92.3% vs. 58.3%, p<0.0001). The CSORN cohort demonstrated significantly greater rates of satisfaction after surgery at 3 months (p=0.003) and 1 year (p<0.001). Conclusions: Patients undergoing surgical treatment for lumbar spinal stenosis in Canada (CSORN cohort) reported higher rates of satisfaction at 3 months and 1 year post-operatively compared to the United States cohort (SPORT) despite having longer durations of symptoms prior to surgery.

Background: Canada has a universal health care system that is funded by the government while the United States utilizes a combined public and private payer system. The purpose of this study is to investigate whether there are differences in clinical outcomes between those surgically treated for lumbar disk herniation in Canada as compared to the United States. Methods: Surgical lumbar disk herniation patients enrolled in the Canadian Spine Outcome Research Network (CSORN) prospective registry. were compared with the surgical cohort enrolled in the Spine Patients Outcome Research Trial (SPORT) study. Spine-related patient reported outcomes (PROs) were compared at 3 months and 1 year. Results: The CSORN cohort consisted of 443 patients and the SPORT cohort was made up of 573 patients. Patients in the CSORN cohort were older (p<0.001), and were more likely to be employed (p=0.003). The CSORN cohort demonstrated significantly greater rates of satisfaction after surgery at 3 months (87.2% vs. 65.5%, p=0.003) and 1 year (85.6% vs. 69.0%, p<0.0001). The CSORN cohort was a significant independent predictor of patient satisfaction at 1 year. Conclusions: Patients undergoing surgical treatment for lumbar disc herniation in Canada reported higher rates of satisfaction at 3 months and 1 year post-operatively compared to the United States.

Background: Peri-operative adverse events (AE) lead to patient disappointment and greater costs. There is a paucity of data on how AEs affect long-term outcomes. The purpose of this study is to examine peri-operative AEs and their impact on outcome after lumbar spine surgery. Methods: 3556 consecutive patients undergoing surgery for lumbar degenerative disorders enrolled in the Canadian Spine Outcomes and Research Network were analyzed. AEs were defined using the validated Spine AdVerse Events Severity system. Outcomes at 3,12, and 24 months post-operatively included the Owestry Disability Index (ODI), SF-12 Physical (PCS) and Mental (MCS) scales, visual analog scale (VAS) leg and back, Euroqol-5D (EQ5D), and satisfaction. Results: Adverse events occurred in 767 (21.6%) patients, 85 (2.4%) suffered major AEs. Patients with major AEs had worse OD (physical disability) scores and did not reach minimum clinically important differences at 2 years (no AE 25.7±19.2, major: 36.4±19.1, p<0.001). Major AEs were associated with worse ODI (physical disability) scores on multivariable linear regression (p=0.011). Conclusions: Major AEs after lumbar spine surgery lead to worse functional outcomes and lower satisfaction. This highlights the need to implement strategies aimed at reducing adverse events.

Background: There is significant heterogeneity in neurological recovery after complete (ASIA A) traumatic spinal cord injury (tSCI). Neurological recovery is often associated with a conversion to a higher letter grade of the American Spinal Injury Association’s impairment scale (ASIA). The mechanism of injury (MOI) may play a significant role in the primary injury and should be considered for greater precision in care. Methods: We isolated ASIA A cervical tSCI patients from three multicenter prospective randomized controlled trials (NACTN, STASCIS, Sygen). Chi-square test with pairwise comparisons with Bonferroni corrections was performed to compare the proportion of ASIA A patients that converted to a higher ASIA grade between different MOI. Results: We identified 486 complete cervical tSCI patients. For patients who developed tSCI as a result of a fall, a significant proportion converted to a higher ASIA grade by 52 weeks (p = 0.009). For patients who developed tSCI as a result of a sports injury, a significantly smaller proportion did not convert to a higher ASIA grade compared to those that converted (p = 0.034). Conclusions: Due to the difference in outcomes, tSCI patients should be treated differently depending on their mechanism of injury.

Background: A non-operative approach has been favoured for elderly patients with lumbar spondylolisthesis due to a perceived higher risk with surgery. However, most studies have used an arbitrary age cut-off to define “elderly.” We hypothesized that frailty is an independent predictor of morbidity after surgery for lumbar spondylolisthesis. Methods: The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for years 2010 to 2018 was used. Patients who received posterior lumbar spine decompression with or without posterior fusion instrumented fusion for degenerative lumbar spondylolisthesis were included. The primary outcome was major complication. Secondary outcomes were readmission, reoperation, and discharge to location other than home. Logistic regression analysis was done to investigate the association between outcomes and frailty. Results: There were 15 658 patients in this study. The mean age was 62.5 years (SD 12.2). Frailty, as measured by the Modified Frailty Index-5 was significantly associated with increased risk of major complication, unplanned readmission, reoperation, and non-home discharge. Increasing frailty was associated with increasing risk of morbidity. Conclusions: Frailty is independently associated with higher risk of morbidity after posterior surgery in patients with lumbar spondylolisthesis. These data are of significance to clinicians in planning treatment for these patients.