bluuebunny/crossref_metadata_2025 huggingface dataset:
P.092 Ommaya reservoir placement for intraventricular chemotherapy: a retrospective case series in the image-guidance era
Authors: Lau JC , Megyesi JF
Published: June 2016

Background: In 1963, Ayub Ommaya proposed a surgical technique for placement of a subcutaneous reservoir and pump to allow access to intraventricular cerebrospinal fluid (CSF). Currently, the most common indication for Ommaya reservoir insertion in adults is for patients with hematologic or leptomeningeal disorders who require repeated injection of chemotherapy into the CSF space. Historically, the intraventricular catheter has been inserted blindly based on anatomical landmarks. The purpose of this study was to determine short-term complication rates from Ommaya reservoir placement in the image-guidance era. Methods: We retrospectively evaluated all operative cases of image-guided Ommaya reservoir insertion from 2004-2014 by the senior author (JFM). Patient demographic data and peri-operative complications were collected. Results: We identified 28 patients over the study period (43.3+/-17.3 years; 64.3% male). Indications for placement included acute lymphoblastic leukemia, diffuse large B-cell lymphoma, and leptomeningeal carcinomatosis. There was one asymptomatic peri-operative intracranial hemorrhage (3.6%), and one early infection (3.6%). All catheters were well-positioned and functional. Conclusions: In our retrospective single-centre case series, all catheters were placed accurately. Our results support routine use of intra-operative image guidance for proximal catheter insertion in elective Ommaya reservoir placement for intraventricular chemotherapy.
P.093 Pulsatile tinnitus due to obstruction of transverse sinus by tentorial meningioma
Authors: Maroun FB , Avery R , Lee B , Bartlett P , Hache N
Published: June 2016

Background: The etiology and treatment of pulsatile tinnitus is difficult and there are different causes for it. To our knowledge, an obstruction of the transverse sinus due to tentorial meningioma has not been reported. Methods: A 66 year old female presented a year ago with a sudden onset of a hissing sound in her ear which has persisted since. Neurologically she was intact. She was seen by otolaryngology who identified no cause for her tinnitus. A CT scan and MRI showed a tentorial meningioma on the right side with partial obstruction of the transverse sinus with evidence of partial chronic thrombus. Results: Removal of the meningioma with decompression of the transverse sinus resulted in immediate disappearance of the pulsatile tinnitus. Conclusions: This report can be added to the etiology of the difficult entity of pulsatile tinnitus particularly as it relates to its management.
P.096 A single institution experience with 217 average risk patients undergoing carotid angioplasty and stenting in the post CREST era, a real life experience
Authors: Drake B , Alizadeh Vakili N , Sarma D , Bharatha A , Marotta T , Montanera W , Chiu A , Spears J
Published: June 2016

Background: The CREST trial remains the most influential study regarding choice of treatment modality for carotid revascularization in the modern era. The effect of the CREST trial on patient outcomes and changes to clinical practice are yet to be fully elucidated. Methods: We report a cohort of 217 consecutive symptomatic average risk patients undergoing CAS at St. Michael’s Hospital, between 2010 and 2016. Outcome measures were stroke, MI and death at 30 days post procedure. Of the 217 patients, 42 were above the age of 75 (19%). Results: The 30-day combined stroke, MI and death outcome for all patients was 4.1%. One death occurred (0.46%) in a patient who suffered an MI. One disabling stroke (0.46%) and 3 mild strokes (1.38%) with full recovery by 6 months occurred. Overall 4 patients suffered an MI (1.84%). Conclusions: As a result of the CREST trial in our single institutional experience there has been a clear migration to treating average risk patients using CAS, a treatment previously reserved for high risk patients. In this average risk cohort we report favourable outcomes when compared to the CREST trial as well as the firmly established benchmarks for CEA complications derived from the NASCET trial.
P.097 Safety of intrarterial reopro in thrombotic complications during coiling
Authors: Martinez-Perez R , Boulton M , Sharma M
Published: June 2016

Background: Abciximab is used for the treatment of thromboembolism occuring during endovascular procedures, however the experience with intra-arterial infusion is limited. The objective is to evaluate its safety and effectiveness during coiling complications. Methods: From an aneurysm coiling database, patients treated with intra-arterial abciximab due to thrombotic complications were selected. Patient were classified either as non-ruptured aneurysm for elective coiling or presenting with subarachnoid hemorrhage. They all had preand post-procedure cerebral angiography performed at our institution as part of routine work-up. Success rate was based on recanalization seen on cerebral angiography. Complications of using abciximab were reported. Results: 35 of 441 coiling patients had a thrombotic complication. 13 of them were treated using intra-arterial infusion of abciximab. 2 patients were male, median age 59. 6 patients presented with sub-arachnoid haemorrhage. 84 % of patients had at least partial recanalization, while 38 % experienced complete recanalization of the parent vessel. 45 % of patients had complications, none severe. 2 patients had aneurysm recanalization, 3 distal migration of thrombus and 1 had haemorrhage (non ruptured aneurysm). Conclusions: Inspite of being considered a safer alternative, use of intrarterial abciximab has potential risks, including hemorrhage, distal thromboembolism and aneurysm recanalization.
P.099 Characteristics of the SOFIA distal access catheter in suction-stentriever acute stroke intervention
Authors: Spinos E , Mattingly TK
Published: June 2016

Background: Tri-axial systems are frequently employed in stroke interventions. In addition to more support, the distal access catheter can provide suction aspiration during a stent retrieval. We have recently adopted the 5F SOFIA as part of a tri-axial system for acute stroke interventions, and believe it has improved efficient recanalization. Methods: This is a retrospective case series of acute stroke interventions utilizing the 5 F SOFIA 125 cm distal access catheter. Cases were evaluated for distal location of the catheter, number of stent-triever passes, and final TICI score. We describe our angiographic technique. Results: Nine acute stroke cases were performed using the SOFIA catheter. LVOs were in the M1(6), M2 (2), distal basilar (1). The 5F SOFIA catheter was advanced into the M1 or Basilar artery in all cases. No dissections or spasm was seen in the catheterized intracranial artery. Mean stent-triever passes was 2 (1-4). Final angiographic results were TICI 3 (6), TICI 2b (2), and TICI 0 (1). Conclusions: Efficient thrombectomy is a key part of successful stroke recanalization. We report on our experience with a specific distal access catheter which has reduced the number of stent passes required to restore flow.
P.103 A spatial analysis of forces applied during virtual reality brain tumor resection: the force pyramid
Authors: Del Maestro RF , Azarnoush H , Siar S , Alzhrani G , Winkler-Schwartz A , Alotaibi F , Bajunaid K , Sawaya R , Bugdadi A , Marwa I
Published: June 2016

Background: Virtual reality simulators allow development of novel methods to analyze neurosurgical performance. Force pyramids provide visual and spatial analysis of 3 dimensional force application by any instrument used during simulated tumor resection. This study was designed to answer three questions: 1) Do study groups have distinct force pyramids? 2) Do handedness and ergonomics influence force pyramid structure? 3) Are force pyramids dependent on visual and haptic characteristics of simulated tumors? Methods: NeuroVR (formerly NeuroTouch), a virtual reality simulator, continually assessed simulated ultrasonic aspirator force application of neurosurgeon, resident and medical student groups during resection of 18 simulated brain tumors with different visual and haptic characteristics. Results: Sixteen neurosurgeons, 15 residents and 84 medical students participated. Neurosurgeon, resident and medical students groups displayed easily distinguishable 3 dimensional ‘force pyramid fingerprints’. Neurosurgeons had the lowest force pyramids, indicating application of the lowest forces, followed by resident and medical student groups. Handedness, ergonomics, visual and haptic tumor characteristics resulted in distinct well-defined 3 dimensional force pyramid patterns. Conclusions: ‘Force pyramid fingerprints’ provide 3 dimensional spatial assessment displays of instrument force application during simulated tumor resections. Neurosurgeon force utilization and ergonomics data form a basis for understanding and modulating resident force application and improving patient safety during tumor resection.
P.104 Glioblastomas located in the right hemisphere are associated with worse quality of life
Authors: Iorio-Morin C , Goffaux P , Descoteau M , Whittingstall K , Fortin D
Published: June 2016

Background: Because glioblastoma is currently incurable, the goal of therapy is the optimization of the patient’s quality of life (QOL). Tumor location is critical in screening surgical candidates, yet the impact of tumor location on QOL has never been demonstrated. By using a novel computer-driven algorithm, we set out to investigate the impact of tumor location on QOL. Methods: The tumors of fourty consecutive glioblastoma patients were segmented and the Euclidian distance between 90 brain regions and each tumor’s margin was calculated and correlated to the patients’ self-reported QOL as measured by the SNAS questionnaire. Results: QOL was statistically associated with proximity to three areas: the right para-hypocampal gyrus, the right posterior cingulate cortex and the right postcentral gyrus. We postulate that the adverse relation between proximity to these areas and QOL results from disruption in large-scale networks involved in high-order functions such as visuospatial memory. While harder to detect with a bedside clinical examination, such deficits are likely more impactful on QOL than those related to the motor cortex or Broca’s area. Conclusions: Tumor proximity to right parietooccipital region are associated with decreased QOL. This should be considered in the management strategies of glioma patients.
P.105 Clinical impact of functional magnetic resonance imaging for pre-operative planning in patients with low grade gliomas
Authors: Kosteniuk SE , Lau JC , Megyesi JF
Published: June 2016

Background: This study aims to evaluate the impact of pre-operative functional magnetic resonance imaging (fMRI) on low grade glioma (LGG) patients’ outcomes. Methods: In this retrospective matched cohort study (N =48) of a single surgeon’s patients, we are comparing two groups of LGG patients (WHO grade II) based on exposure to fMRI. A 1:2 propensity score match from a pool of 764 brain tumour patients was performed. Results: Within the group of 16 LGG patients who have undergone fMRI studies over a 12-year period, mean age was 40 years, and most presented with seizures (81%). Most lesions were left-sided (81%), and the lobes most commonly involved were frontal (75%) and temporal (31%). Patients underwent either craniotomy (50%), stereotactic biopsy (25%) or nonsurgically management (25%). In surgical patients, between presurgical assessment and eight week post-surgical follow-up, mean modified Rankin scale improved from 1.80±0.79 to 1.50±0.97. In our cohort, 5-year mortality was 12.5% (patients followed for a mean duration of 5.46 years). Conclusions: Data analysis is ongoing with plans to compare relevant demographics and outcomes via 1:2 propensity score matching of LGG patients who underwent fMRI against a control cohort.
P.106 Thrombospondin 1 mediates transforming growth factor beta induced premature senescence in primary glioblastoma cells
Authors: Kumar R , Lorimer I
Published: June 2016

Background: Glioblastoma is the most common primary malignant brain tumor. Primary Glioblastoma (PriGO) cells are key drivers of glioblastoma. Senescence is the irreversible growth arrest of cells with continued metabolic activity. Recently, I discovered PriGO cells undergo premature senescence in response to Fetal Bovine Serum (FBS). Determining the underlying molecular mechanisms may allow development of novel therapeutic strategies to decrease the malignant potential of glioblastoma. Methods: Global gene expression changes in PriGO cells treated with serum were analyzed and compared to untreated cells. Senescence was determined by the Senescence-Associated-Beta-Galactosidase (SA-B-Gal) assay. Results: PriGO cells treated with serum demonstrated increased expression of genes in the Transforming Growth Factor Beta (TGF-B) pathway, such as Thrombospondin 1 (TSP1), compared to untreated cells. TGF-B treatment of PriGO cells significantly increased senescence compared to untreated cells. Treatment of PriGO cells with serum and the TGF-B inhibitor SB431542 led to a decrease in senescence compared to serum only treated cells. Treatment of PriGO cells with serum and the TSP1 inhibitor LSKL led to a reduction in senescence compared to serum only treated cells. Conclusions: Our data identifies TGF-B as an important component of serum responsible for inducing senescence in PriGO cells. Furthermore, TGF-B induced senescence in PriGO cells is in part mediated by TSP1.
P.114 Flow diversion of bifurcation aneurysms is more effective when the jailed branch is occluded: an experimental study in a novel canine model
Authors: Darsaut T , Fahed R , Gevry G , Gentric J , Salazkin I , Raymond J
Published: June 2016

Background: Flow diverters (FDs) are increasingly used for bifurcation aneurysms. Failure of aneurysm occlusion may be caused by residual flow maintaining patency of the jailed branch along with the aneurysm. Methods: Sixteen wide-necked lingual-carotid artery bifurcation aneurysms were created in 8 canines. Patent aneurysms were randomly allocated 4 weeks later to flow diversion combined with jailed branch occlusion using coils and/or Onyx (n=6) or flow diversion alone (n=8). Angiographic results of aneurysm occlusion at three months were scored using an ordinal scale. Pathology specimens were photographed and neointimal coverage estimated. Results: Fourteen aneurysms were patent at one month. FD deployment was successful in all cases, but at 3 month follow-up, 3 devices had prolapsed into the aneurysm. None of the bifurcation aneurysms treated with FD alone were occluded at 3 months. Endovascular branch occlusion combined with flow diversion significantly improved aneurysm occlusion rates (median angiographic score of 2) compared to flow diversion alone (median score of 0: P=0.0137). Flow-limiting parent vessel stenosis was not observed in any arteries. Devices were covered with thick neointima in most cases. Conclusions: Treatment failures following flow diversion of bifurcation aneurysms can be caused by persistent flow to the jailed branch. Branch occlusion combined with flow diversion may improve angiographic occlusion of canine aneurysms.
P.123 Assessing level of awareness, attitudes and believes toward pediatric congenital neurosurgical conditions
Authors: Hasen MA , Ammar A
Published: June 2016

Background: Community awareness, attitudes and beleifs toward pediatric patients diagnosed with congenital neurosurgical conditions is not known in the Saudi population and the number of studies is few worldwide. Such attitudes have a direct impact on the quality of life of patients with these congenital conditions. This study aims to demonstrate the variation in awareness, attitudes and believes in the public and among health-care professionals towards patients diagnosed with congenital neurosurgical conditions and its associated factors. Methods: A survey consisting of 36 questions pertaining to Hydrocephalus, Brain Tumors and Spina Bifida awareness, attitudes and believes was distributed to Saudi citizens living in the eastern province older than 15 years of age among hospitals visitors, medical students, nutritionists, physicians, dentists, pharmacists, and nurses. Results: The analysis of the 1002 respondent of the questionnaire shows clear social stigmata and improper awareness, attitudes and believes toward pediatric patients diagnosed with congenital neurosurgical conditions. There are variable parameters on interest measured and analyzed and there are certain patterns observed as well. Conclusions: The analysis showed the importance of health education for the public to increase the level of awareness and it justifies why these factors should be addressed in the middle of patients’ management, community awareness and health planning.
P.133 A retrospective analysis of the clinical utility of the Tokuhashi scale, and its impact in surgical management of spinal metastatic disease
Authors: Leck E , Dakson A , Butler M , Thibault-Halman G , Christie S
Published: June 2016

Background: The evaluation of patients presenting with spinal metastatic disease is often challenging. The Tokuhashi scale intends to facilitate this process. We conducted this study to investigate its clinical utility in surgical-decision making in patients with spinal metastasis. Methods: The oncology database was used to allocate 285 patients with spinal metastasis between 2010 and 2015. The Tokuhashi scale components were determined from a chart review. Results: Based on the Tokuhashi scale, there was 69.1% in the non-operative/radiation group (group 1), 23.2% in the palliative/excisional surgical group (group2) and 7.7% in the surgical group (group 3). Using Kaplan-Meiers estimate, survival time was significantly different across the three groups with means 232.8±30.8, 352.3±49.2 and 568.3±206.1 days, respectively. A significantly higher proportion of patients (84.6%) were treated non-surgically in group 1, compared to 45.5% in group 3 (X2=19.5, P<0.001). However, there was no correlation between the type of surgical interventions (i.e. instrumented decompression, decompression alone, percutaneous vertebral augmentation and instrumented vertebral augmentation) and the Tokuhashi score. Conclusions: This review illustrates the utility of the Tokuhashi scale in predicting survival. However, it does not address the new role of emerging different surgical strategies for the treatment of spinal metastasis and lacks information concerning spinal instability.
P.135 Epidemiology of spine infection in patients with history of IV drug use and HIV infection. Possibility of the secondary prevention
Authors: Meguro K , Meili R , Pirlot B , Ahmad U
Published: June 2016

Background: One of the major risk factors for spine infection is IV drug use and HIV infection. An increase in these risk factors has coincided with increased rates of spinal infection in Saskatchewan. However, the exact incidence and the clinical significance of spine infection associated with high-risk behavior is poorly understood. Methods: A retrospective review was completed for adult patients with discitis, osteomyelitis, or epidural abscess admitted to the Royal University Hospital, University of Saskatchewan over the last eight years. Results: This study included 176 patients consisting of 41% with discitis, 69% with osteomyelitis and 45% with epidural abscess. Overall mortality was 3% and 16% of patients developed severe disability.40% of patients were intravenous drug users, 45% were hepatitis C positive and 12% were HIV positive. For the initial four years of our study we experienced 72 patients. We experienced 91 cases over the past four years. Geographical analysis showed high incidence areas within the city of Saskatoon. Conclusions: High rates of IV drug use, Hepatitis C, and HIV have important implications in terms of what measures would assist in prevention of this condition. Secondary prevention or early identification of patients may reduce the number of patients who require lengthy admission, surgery and long term care for disablity.
P.137 Biomechanical evaluation of the ProDisc-C stability following graded posterior cervical injury
Authors: Staudt MD , Rabin D , Baaj AA , Crawford NR , Duggal N
Published: June 2016

Background: There is limited data regarding the development of persistent or recurrent symptoms, and the implications of revision posterior surgery in the setting of previous cervical arthroplasty (CA). The purpose of this study was to analyze segmental kinematics in human cadaveric specimens with and without CA, in the context of graded posterior resection. Methods: Fourteen human cadaveric cervical spines were divided into arthroplasty (ProDisc-C) and control (intact disc) groups. Both groups underwent sequential posterior element resections: unilateral foraminotomy, laminoplasty, and finally laminectomy. Specimens were studied sequentially in two different loading apparatuses during induction of flexion-extension, lateral bending, and axial rotation. Results: Range of motion (ROM) after CA was reduced relative to the control group during axial rotation and lateral bending, but was similar during flexion and extension. With sequential resections, ROM increased by a similar magnitude following foraminotomy and laminoplasty. Laminectomy had a much greater effect following CA compared to the control group, with the largest magnitude of increase in flexion and extension. Conclusions: Foraminotomy and laminoplasty do not seem to induce greater instability in the setting of CA, compared to controls. Laminectomy alone would not be recommended for use with arthroplasty due to the significant change in kinematics, especially in flexion and extension.
A.02 Clinical clues for autoimmunity in the etiology of autistic regression
Authors: Goez H , Scott O , Shi D , Andriashek D , Clark B
Published: June 2016

Background: Autistic regression (AR) accounts for 20-40% of patients with Autism Spectrum Disorder (ASD) .1 Literature demonstrates specific immune changes in AR patients,2 as well as association between AR and autoimmune thyroiditis.3 Our study explores the clinical association between AR and autoimmunity, focusing on possible precipitants and familial autoimmunity, in comparison with patients with infantile autism (IA). Methods: charts of children diagnosed with ASD in 2014 were reviewed, and patients were classified as either AR or IA based on Autism Diagnostic Interview (ADI-R) criteria.4 Information regarding pregnancy, perinatal complications, febrile illness preceding the diagnosis, and family history of autoimmune conditions was collected. Results: 206 children had IA and 33 had AR. No difference was found in prevalence of pregnancy or perinatal complications. The incidence of febrile illness in the 6 months prior to diagnosis and the prevalence of familial autoimmunity, were significantly higher in the AR group (p<0.001). Diabetes type I, celiac disease, autoimmune thyroiditis, and inflammatory bowel disease were more common in families of AR patients (p<0.05). Conclusions: the association between AR and preceding febrile illness, as well as familial autoimmunity, supports the notion of AR as a separate entity within ASD, possibly mediated by autoimmune changes.
A.03 Cerebral perfusion and its relationship to post-concussion syndrome in mild traumatic brain injury: a prospective controlled cohort study
Authors: Barlow KM , Marcil LD , Dewey D , Carlson H , MacMaster FP , Brooks BL , Lebel RM
Published: June 2016

Background: Persistent post-concussive symptoms (PCS) have been linked to increased cortical network activation and decreased cerebrovascular reactivity. Decreased cerebral perfusion could help explain PCS and may be a biomarker to track recovery. Methods: Children (ages 8 to 18 years) symptomatic with PCS at one month post-injury were studied. Children who recovered following a mTBI (asymptomatic group) and healthy children acted as controls. Pseudocontinuous arterial spin labeling MRI was used to quantify cerebral blood flow (CBF). All subjects were imaged at approximately 40 days post-injury. Symptomatic group underwent repeat neuroimaging 4-5 weeks later. Results: Seventy-two participants (14.1 years; 95% CIs: 13.5, 14.8) underwent neuroimaging at 40 days post-injury. Global CBF was significantly higher in the symptomatic group compared to healthy controls, and lower in the asymptomatic group (F(2,57) 9.734 p<0.001). Symptomatic children had increased CBF in the frontal and occipital regions, and asymptomatic children had decreased CBF in the temporal regions compared to healthy controls. CBF decreased in symptomatic children over time. CBF was a predictor of cognition (R2=0.235;p=0.001). Conclusions: Cerebral perfusion is altered in children with mTBI and is associated with recovery trajectory. Asymptomatic children had decreased CBF suggesting cerebral recovery is ongoing. Further longitudinal studies are required to determine if these perfusion patterns continue to change over time.
A.05 Ten years of experience with lamotrigine for the treatment of neonatal and infantile seizures
Authors: St-Arnaud A , Proulx É , Thibeault-Eybalin M , Calon F
Published: June 2016

Background: The therapeutic value of second-generation anticonvulsants such as lamotrigine has not been clearly established in neonates and infants with seizures. To address this issue, we assessed the efficacy of lamotrigine for treating neonatal and infantile seizures, detailed the dosing regimens used, and described its tolerability and safety profile. Methods: This retrospective study included patients (age 0-12 months) diagnosed with seizures and treated with lamotrigine, as monotherapy or adjunctive therapy, by pediatric neurologists at Centre mère-enfant Soleil du CHUQ from 2004 to 2014. The frequency of seizures and EEG patterns were compared before and after introduction of lamotrigine during the first months of life. Data on initial and maintenance doses, rate and magnitude of dosing increments, and adverse effects were collected. Results: Treatment with lamotrigine was initiated in 32 neonates and 13 infants. At first follow-up (mean duration 3 months), 76 % (n = 34) showed a significant (≥50%) reduction of seizures and 64% (n= 29) improvement of EEG pattern compared to baseline. The efficacy in monotherapy and adjunctive therapy was similar. A single case of cutaneous hypersensitivity reaction requiring cessation of treatment was reported. Conclusions: This study suggests that lamotrigine is a useful, safe, and well-tolerated anticonvulsant alternative for the treatment of seizures in neonates and infants.
B.02: Burst-suppression EEG is reactive to photic stimulation in comatose children with acquired brain injury
Authors: Nita DA , Moldovan M , Sharma R , Avramescu S , Otsubo H , Hahn CD
Published: June 2016

Background: Burst-suppression is an electroencephalographic pattern observed during coma and reflects severe encephalopathy. We investigated the reactivity of burst-suppression to photic stimulation in children with acquired brain injury. Methods: Intensive care unit electroencephalographic monitoring recordings containing burst-suppression were obtained from 5 comatose children with acquired brain injury of various etiologies. Intermittent photic stimulation was performed at 1 Hz for 1 minute to assess reactivity. We quantified reactivity by measuring the change in the burst ratio (fraction of time in burst) following photic stimulation. Results: Photic stimulation evoked bursts in all patients, resulting in a transient increase in the burst ratio, while the mean heart rate remained unchanged. The regression slope of the change in burst ratio, referred to as the standardized burst ratio reactivity, correlated with subjects’ Glasgow Coma Scale scores. Conclusions: Reactivity of the burst-suppression pattern to photic stimulation occurs across diverse coma etiologies. Standardized burst ratio reactivity appears to reflect coma severity. Measurement of burst ratio reactivity may represent a simple bedside tool to monitor coma severity in critically ill children.
B.07 Evaluating the single seizure clinic model: findings from a Canadian centre
Authors: Rizvi SA , Hernandez-Ronquillo L , Moien-Afshari F , Hunter G , Tellez-Zenteno JF , Waterhouse K
Published: June 2016

Background: The effect of the single seizure clinic (SSC) model on patient diagnosis, work-up, wait-times, and clinical care is poorly characterized. This study assesses patient characteristics and evaluates the impact of a SSC model on wait-times and access to care. Methods: A prospective study of all patients (n=200) referred to our SSC for first-seizure evaluation. Demographic, clinical, and paraclinicial variables were analyzed against a historical cohort. Binary logistic regression analysis was performed to predict impact of dichotomized variables on diagnosis of epilepsy. Diagnostic concordance between SSC nurses and epileptologists was also assessed. Results: Predominant referral sources were emergency department physicians and general practitioners. Mean wait-time for first assessment was significantly reduced by 70.5% employing the SSC model versus historical usual care. A diagnosis was established at first-contact in 80.5% of cases while 16.0% of patients required a second visit. Eighty-two patients (41.0%) were diagnosed with epilepsy. The most common non-seizure diagnosis was syncope (24.0%). An abnormal EEG was found in 93.9% of patients diagnosed with epilepsy. Sixty-three patients were started on anti-epileptic drugs. In 18% of cases driving restrictions were initiated by the SSC. There was moderate correlation between SSC nurses and physicians (kappa=0.54; p<0.001) diagnoses. Conclusions: The SSC model reduces wait-times, streamlines assessments, and impacts clinical care decisions.
C.03: Progressive contralateral hippocampal atrophy following surgery for medically refractory temporal lobe epilepsy
Authors: Elliott CA , Gross D , Wheatley B , Beaulieu C , Sankar T
Published: June 2016

Background: It remains difficult to predict which patients will experience ongoing seizures or neuropsychological deficits following Temporal Lobe Epilepsy (TLE) surgery. MRI allows measurement of brain structures, such as the contralateral (non-resected) hippocampus (cHC) after TLE surgery. Preliminary evidence suggests that the cHC atrophies following surgery, however, the time course of this atrophy, relation to cognitive deficits and seizure outcome remains unclear. Methods: T1-weighted MR imaging and hippocampal volumetry in 26 TLE patients pre- and post-TLE surgery (and 12 controls) as: 1) two-scan group (TSG) (pre- and post-operatively at 5.4 years) and 2) longitudinal group (LG; pre- and on post-operatively on day 1,2,3,6,60,120 and at an average 2.4 years. Seizure outcome and pre- and post-operative neuropsychological assessment was performed. Results: The TSG had significant atrophy by 12% of the unresected cHC (p<0.0001) most pronounced (27%) in the hippocampal body alone. The LG revealed that this atrophy occured rapidly over the first week (1.3%/day; 3%/day cHC body). Significantly greater cHC atrophy was observed in those with ongoing seizures versus the seizure free (p=0.048). Conclusions: Significant cHC atrophy following TLE surgery that begins immediately, progresses over the first week, and remains signficantly depressed. The severity postoperative cHC atrophy may represent an early biomarker of the propensity for delayed seizure recurrence.
C.04: Motor cortex electrical stimulation to promote spinal cord injury repair in an animal model
Authors: Jack A , Nataraj A , Fouad K
Published: June 2016

Background: Electrical stimulation (ES) to promote corticospinal tract (CST) repair has been recently examined, though remains under investigated. We examine the role of motor cortex ES on axonal re-growth and functional recovery in a spinal cord injury (SCI) rat model. Methods: A partial transection was performed at C4 in 48 rats. Animal groups included: ES333 rats (n=14; 333Hz, biphasic pulse, 0.2ms every 500ms), ES20 (n=14; 20Hz, biphasic pulse, 0.2ms every 1ms), SCI only (n=10), and sham (n=10; electrode insertion without ES). Rats were trained in stairwell-grasping with subsequent SCI and ES. Post-injury reaching scores were recorded weekly, and histology completed quantifying axonal re-growth. Results: Post-SCI grasping (p<0.01, ANOVA) and well reached were lower than baseline values (p<0.01, ANOVA) for all groups. ES20 animals had lower grasping scores (p=0.03, ANOVA) and farthest well reached scores post-SCI than controls (p=0.03, ANOVA). ES333 rats had more axonal collaterals (axonal sprouts rostral to lesion) compared to control animals (p<0.01, M-W). No difference was found between groups with respect to axonal regeneration into the lesion (p=0.13, ANOVA). Conclusions: Cortical ES of the injured CST results in greater axonal outgrowth, and influences functional outcomes depending on ES parameters. ES is a potentially promising SCI therapy, but further investigation is required.
C.06 Surgical resection of pediatic posterior fossa tumours in the molecular era
Authors: Ramaswamy V , Thompson E , Taylor MD
Published: June 2016

Background: Aggressive surgical resections of posterior fossa tumours result in tremendous neurological sequelae as a result of damage to the brainstem. As such we sought to re-evaluate the role of aggressive surgical resections in the molecular era. Methods: 820 posterior fossa ependymoma and 787 medulloblastoma were genomically profiled and correlated with pertinent clinical variables. Results: Across 787 medulloblastoma cases, the value of extent of resection was greatly dampened when accounting for molecular subgroup. Near-total resections are equivalent to gross total resections across all four subgroups even when correcting for treatment. The prognostic value of a gross total resection as compared to a subtotal resection (>1.5cm2 residual) was restricted to Group 4 tumours (HR 1.26). Across 820 posterior fossa ependymoma PFA ependymoma was a very high risk group compared to PFB ependymoma, and a subtotal PFA ependymoma conferred an extremely poor prognosis. Gross totally resected PFB ependymoma could be cured with surgery alone. Prognostic nomograms in both medulloblastoma and ependymoma revealed molecular subgroup to be the most important predictor of outcome. Conclusions: The prognostic benefit of EOR for patients with medulloblastoma is marginal after accounting for molecular subgroup affiliation. In both molecular subgroups of posterior fossa ependymoma, gross total resection remains an important predictor of outcome.
D.01 Earlier treatment with the Ketogenic Diet improves seizure outcome in early-onset drug-resistant epilepsy
Authors: Irwin M , Aimola S , Lowe H , Liu Y , Zak M , Chan V , Kobayashi J , Donner EJ
Published: June 2016

Background: The ketogenic diet (KD) is used to treat severe childhood-onset epileptic encephalopathies, such as Infantile Spasms (IS). Unfortunately, limited resources for KD initiation result in treatment delays. We ask if earlier KD treatment of early-onset drug-resistant epilepsy results in better seizure outcomes. Methods: Children who started KD before age 4 years between 2000-present at SickKids Hospital were identified. Six-month seizure outcome was calculated as percent of pre-diet baseline seizure frequency (BSF). Results: 67 children were identified. 30 (44.8%) started KD <2 years old, 37 (55.2%) started KD 2-4 years old. Among <2 years old group, 83.3% achieved 50% reduction in BSF and 36.7% achieved 90% reduction. Among 2-4 year old group, 62.2% achieved 50% reduction in BSF and 24.3% achieved 90% reduction. 38 children had a history of IS; 17 with IS at diet initiation and 21 with past history of IS. 41.2% of the spasms cohort achieved 90% reduction in BSF, compared to 23.8% of the post-spasms cohort. Conclusions: KD was more effective when started before age 2 years than 2-4 years, and more effective in children with IS than in children with past history of IS. A rapid protocol for KD initiation in young infants and children may improve long-term outcomes
D.03 Down syndrome: clinical and EEG correlates during development
Authors: Nauth S , Bamaga AK , Cortez MA
Published: June 2016

Background: Down syndrome (DS) is the primary genetic cause of mental retardation and seizures are present in an estimated 5-13% of cases. One-third of seizures in DS are infantile spasms (IS). Hypsarrythmia (HS) is the cardinal electroencephalogram (EEG) feature of IS and has been found to affect cognition; however, its effect on DS patients is inconclusively reported. This study assesses the correlation of HS with cognitive outcomes in DS using the largest sample size to date. Methods: Retrospective study of medical records of children with DS [0-18yrs] at SickKids Hospital in Toronto, from 1990-2013. Seizure history, EEG findings, comorbities, and pharmacological treatments were identified. Developmental outcomes were also assessed from physician comments on motor, verbal and cognitive abilities. The cognitive outcomes of DS patients with and without HS were compared. Results: 70 [male=40] patients with DS and seizures were included. Among 31 (44.2%) patients with DS and IS, 27 had HS. Chi-square analysis showed a significant difference [P=0.007] in prevalence of severe developmental delay in patients with IS and HS versus all other seizure types. Conclusions: The developmental outcome of patients with Down syndrome appears to worsen when IS and HS had occurred in the first year of life.
D.08 ACT DMD (Ataluren Confirmatory Trial in Duchenne Muscular Dystrophy): effect of Ataluren on timed function tests (TFT) in nonsense mutation (nm) DMD
Authors: Goemans N , Campbell C , McDonald CM , Voit T , Luo X , Elfring G , Kroger H , Riebling P , Ong T , Spiegel R , Peltz SW , Bushby K
Published: June 2016

Background: Ataluren is the first drug to treat the underlying cause of nmDMD. Methods: ACT DMD is a Phase 3, randomized, double-blind study. Males 7-16 years with nmDMD and a screening six-minute walk distance (6MWD) ≥150 m and <80%-predicted were randomized to ataluren 40 mg/kg/day or placebo for 48 weeks. A pre-specified subgroup included patients with baseline 6MWD 300-400 m. A meta-analysis of the overall ACT DMD population and the ‘ambulatory decline phase’ subgroup of the Phase 2b study (those patients meeting ACT DMD entry criteria) was pre-specified in the statistical plan. Results: In the overall ACT DMD population (N=228), changes in TFTs favored ataluren over placebo: 10-meter walk/run, -1.2s (p=0.117); 4-stair climb, -1.8s (p=0.058); 4-stair descend, -1.8s (p=0.012). In the pre-specified subgroup (n=99), these differences increased to -2.1s, -3.6s, and -4.3s, respectively, and were statistically significant (p<0.01) for 4-stair climb and descend. Results are supported by the meta-analysis (N=291), which demonstrated significant differences (p<0.05) in 10-meter walk/run, 4-stair climb, 4-stair descend. Conclusions: TFT results showed a benefit for ataluren in ACT DMD, and a larger treatment effect in the pre-specified baseline 6MWD 300-400 m subgroup as well as the pre-specified meta-analysis of ACT DMD and the Phase 2b study decline subgroup.

Supported By: PTC Therapeutics Inc.
E.02 Streamlining hyperacute stroke management at Royal University Hospital
Authors: Szmigielski AJ , Whelan R , Graham B , Hunter G , Peeling L , Kelly M
Published: June 2016

Background: The Saskatoon stroke program participated in the ESCAPE trial looking at rapid endovascular revascularization for large vessel occlusion. Improvements were necessary to meet the timelines mandates in ESCAPE and to comply with Canadian Best Practice Guidelines. Methods: Retrospective chart review and prospective gathering of key metrics was performed using REDCap (Research Electronic Data Capture) software. Changes adapted from Canadian Best Practice Recommendations for Stroke Care, the ESCAPE protocol, and the Calgary stroke program HASTE project were implemented. Results: Changes implemented included increasing ambulance bypass window to 12 hours, FAST stroke assessment, emergency department pre-notification and registration, stroke alert protocol, team swarm of the patient, administration of tPA in the computed tomography (CT) room, and rapid access to the endovascular suite. Total number of patients between the years 2012 and 2014 was 287, and of those, 93 received tPA. Door-to-CT times decreased from 40 minutes to 21 minutes from 2012 to 2014; and Door-to-Needle (tPA) decreased from 62 minutes to 46 minutes from 2012 to 2014. Conclusions: By following Canadian best practice recommendations for stroke care, the ESCAPE protocol, and adaptation of Calgary stroke program HASTE project, our stroke program implemented changes to reduce treatment times for patients experiencing stroke in our province.
E.03 Use of intra-arterial milrinone rescue therapy in patients with refractory and super refractory vasospasm after aneurysmal subarachnoid hemorrhage
Authors: Alamri AS , Alturki A , Tampeiri D , Angle M , Lo B , Lannes M , Badawy M , Teitelbaum J
Published: June 2016

Background: Vasospasm causing delayed ischemic neurologic deficit (DIND) remains a leading cause of devastating outcome after aneurysmal subarachnoid hemorrhage (aSAH). Therapy using intravenous milrinone (IVM) and intra-arterial milrinone (IAM) has been described. We report our results using IAM in patients with refractory and super refractory vasospasm (RV and SRV respectively). Methods: Retrospective single center study of all adult patients treated with IAM between 2006 and 2016 inclusively. IAM was used as part of the Montreal Neurological Hospital Protocol when the patients’ symptoms failed to respond to initial and higher IVM doses. We report their clinical outcomes. Results: IAM was used in 19 patients. The median loading dose was 8 mg and average maintenance dose was 0.78 mcg/kg/min. Angiographic improvement was seen in 15 (79%) and clinical improvement - within the first 48 hours - was seen in all patients. The median mRS was 3 at time of discharge and 1 three months later. Five patients lost follow up. Conclusions: IAM appears to be safe and effective in this small retrospective series of RV and SRV complicating aSAH. Angiographic and clinical improvements were observed. Further prospective studies are warranted to confirm these findings.
E.08 Subcutaneous vs. intravenous immunoglobulins for chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy
Authors: Racosta JM , Sposato LA , Baker J , Kimpinski K
Published: June 2016

Background: Background: High-dose intravenous immunoglobulin (IV-Ig) is an evidence-based treatment for chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). Recently, subcutaneous Ig (SC-Ig) has received increasing attention. We performed a meta-analysis to assess the efficacy of SC-Ig versus IV-Ig. Methods: Methods: We searched PubMed, Embase, and Scopus from January, 1990 to December, 2015 for publications comparing IV-Ig vs. SC-Ig in patients with CIDP or MMN. We performed fixed-effects meta-analyses for strength changes as measured by the Medical Research Council sum score changes (MRC-SS). Results: Results: A total of 8 studies comprising 138 patients (88 with CIDP and 50 with MMN) were included in the meta-analysis. Considering the total population the use of SC-Ig showed slightly better results for MRC-SS (ES=-1.78, 95%CI=-3.45 to -0.11, I2<0.001%). However, when CIDP and MMN were compared separately, there were no differences between treatments (CIDP: ES=-0.28, 95%CI=-0.57 to 0.02, I2<0.001%; MMN: ES=-0.34, 95%CI=-3.99 to 3.31, I2<0.001%). Conclusions: Conclusions: We found comparable efficacy between SC and IV-Ig administrations for CIDP and MMN. These results suggest that SC-Ig is a suitable alternative treatment method, especially when other situations (e.g. convenience, safety profile) warrant its use. Further studies are needed to explore the efficacy of SC-Ig for CIDP and MMN.
E.09 Predictors of optimal endovascular therapy results among patients with acute ischemic stroke
Authors: Catana D , Badhiwala J , Koziarz A , Reddy K , Almenawer SA
Published: June 2016

Background: Several studies have demonstrated the safety and efficacy of endovascular therapy for patients with acute ischemic stroke. However, patient, imaging and treatment factors associated with the optimal functional outcome require better definition. Methods: We pooled data from 8 randomized controlled trials (SYNTHESIS, MR RESCUE, IMS III, MR CLEAN, ESCAPE, EXTEND-IA, SWIFT-PRIME, and REVASCAT). We conducted subgroup and sensitivity analyses to evaluate predictors of optimal functional results (modified Rankin scale, mRS) at 90 days. Results: Meta-analysis of 8 trials including 2,423 patients yielded that endovascular therapy resulted in 44.6% functional independence (mRS 0-2) versus 31.8% in the usual care group (OR 1.71, 95% CI 1.18-2.49, P=0.005). This treatment effect was significantly greater among patients with confirmed angiographic imaging of proximal arterial occlusion (OR 2.24, 95% CI 1.72-2.90, P<0.001), in patients who received the combined therapy of intravenous tPA and endovascular intervention (OR 2.07, 95% CI 1.46-2.92, P<0.001), and when using stent retriever for mechanical thrombectomy (OR 2.39, 95% CI 1.88-3.04, P<0.001). Conclusions: The relative functional benefit associated with endovascular therapy among patients with acute ischemic stroke was increased when combined with intravenous tPA, with confirmed proximal arterial occlusion on angiographic imaging, and with use of stent retrievers for mechanical thrombectomy.
F.02 Towards the complete control of brain metastases using surveillance screening and stereotactic radiosurgery
Authors: Wolf A , Kvint S , Silverman J , Kondziolka D
Published: June 2016

Background: The incidence of brain metastases is increasing with the development of improved systemic therapies with limited impact on intracranial disease. The purpose of this study was to determine if there is a threshold tumor size below which local control (LC) rates approach 100% after stereotactic radiosurgery (SRS). Methods: 200 patients with 1237 tumors were identified from a prospective registry of patients having undergone SRS between 2012-2014. Histology consisted predominantly of non-small cell lung cancer (NSCLC), melanoma and breast cancer. Results: The median tumor size was 6 mm in diameter or 70 mm3 and most commonly NSCLC. Thirty-three tumors had local progression at a median time of 8.8 months. The 1- and 2-year actuarial LC for all tumors were 97% and 93%. LC of 100% was seen for intracranial metastases less than 100 mm3 or 6 mm in diameter, independent of histology. Total tumor volume was an independent predictor of overall survival, after adjusting for age, KPS and extracranial disease status. Conclusions: SRS can achieve LC rates approaching 100% for subcentimeter metastases. The earlier detection and prompt treatment of small intracranial metastases may prevent the development of neurological symptoms, the need for surgical resection, and potentially improve overall survival. The results of this study would favour the implementation of routine staging MRIs.