bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of professional competencies for touch screen technique in electrical engineering
Authors: Shyr Wen‐Jye , Lin Chia‐Ming
Published: June 2016

This study sought to identify the competency requirements for students in electrical engineering, specifically those that are needed for the design of touch screen interfaces. Using the Hybrid Behaviorally Anchored Rating Scale, this study drew on expert opinion to formulate a list of competencies, and empirically tested the validity and relevance of this list through a survey distributed to a separate group of experts. We identified 36 competencies considered essential for effective performance design of touch screen interfaces in electrical engineering. This study provides a valuable reference to educators in the field of engineering and technology who are involved in training and development programs. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Optimal worst case solutions for state estimation of power system with uncertain network parameters
Authors: Rakpenthai Chawasak , Uatrongjit Sermsak
Published: June 2016

This paper addresses the problem of power system state estimation under the condition that transmission line network parameters are unknown but bounded. A robust estimation in the sense of an optimal worst case solution is determined. Data collected via remote terminal units, i.e. voltage magnitude, power flow, and power injection, are used as measurement quantities. The state variables are bus voltage phasors expressed in rectangular coordinates. This makes it possible to express the relations between measured data and state variables as quadratic functions. The proposed formulation based on the structured robust least squares optimization yields a minimization problem with bilinear matrix inequality constraints. A solution method based on semidefinite programming is also presented. Some test results on the standard IEEE test systems are given. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
An inverse‐time low‐impedance protection design for feeders in active distribution networks
Authors: Wentao Huang , Nengling Tai , Chunju Fan , Dawei Liu
Published: June 2016

One of the major issues associated with active distribution networks (ADNs) is to devise an appropriate protection scheme that works successfully in different operation modes. This paper describes the design of an inverse‐time low‐impedance (ITLI) protection scheme with the aid of the advanced measurement technologies in ADNs. The scheme detects faults and calculates tripping time by using the magnitude ratio of the maximum load impedance to the measured impedance. ITLI protection is immune to varying fault current caused by the flexible operation modes and able to automatically adjust fault‐tripping time according to the fault severity. With the existing communication infrastructures, an event‐triggered adaptive setting scheme updates the settings of ITLI relays in real time. The setting method not only enhances the detecting capability but also provides higher reliability and sensitivity before, during, and after events in ADNs, such as tap position adjustment, DGs fluctuation, and network structure change. Besides, an acceleration method based on the definite‐time grading technique is presented to reduce the impact of infeeds and fault resistance. The effectiveness of the proposed protection scheme is demonstrated in a 12.47‐kV active distribution network established by PSCAD/EMTDC. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
A robust power flow model for active power flow control via thyristor‐controlled series compensator
Authors: Yalcin Faruk
Published: June 2016

In this paper, a new power flow model for active power flow control through a thyristor‐controlled series compensator (TCSC) in an AC network system is proposed. The proposed power flow model is based on the Newton–Raphson method. In this model, TCSC's admittance effect is included as a state variable into the Jacobian matrix to avoid the divergence problem. Unlike similar studies in the literature, TCSC's admittance is ignored in the bus admittance matrix, and the need for rebuilding the bus admittance matrix in each power flow iteration caused by the change of TCSC's admittance is prevented. So, faster convergence for power flow calculation is achieved. For this aim, new power equations are obtained. Also, in the proposed approach, we need not consider each terminal of TCSC as an individual bus in the power flow calculation. Thus, increasing the Jacobian and bus admittance matrixes sizes caused by the total bus number is prevented. The proposed approach is tested on an IEEE 57‐bus test system. The obtained results prove that this approach provides efficient, reliable, and fast convergence. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Prototype implementation of fast and secure traceability service over public networks
Authors: Tennekoon Rajitha , Wijekoon Janaka , Harahap Erwin , Nishi Hiroaki
Published: June 2016

Internet communication message protocol (ICMP)‐based traceability methods are widely used to trace packets over the Internet; however, in their attacks, adversaries likewise use ICMP packets. Furthermore, the lack of security in ICMP‐based traceability results in failures for many current traceability methods. Moreover, current routers are unable to provide extended services to Internet users and applications. To address this need, our laboratory has introduced the service‐oriented router (SoR). SoR is middleware that can be implemented on a Cisco AXP and Juniper JunosV App Engine. In this paper, we propose a secure method of providing packet traceability over public networks using SoR features. We implemented a secure packet traceability service prototype on the ns‐3 simulator. The test results conclude that there is a maximum additional cost of 48.69 and 123.91 μs of processing overhead per packet in each hop when the proposed secured traceability service is used with a 128‐bit key space in AES‐GCM and AES‐CTR modes, respectively. Moreover, for 256‐bit key spaces, AES‐GCM and AES‐CTR modes consumed additional 47.18 and 123.25 μs, respectively, over the plain traceability. Yet, from the evaluations on the test bed topology, it clearly shown that the proposed method was 79% faster than the conventional trace route method in providing the secured end‐to‐end traceability. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Combinatorics‐based estimation of reachable states for the system of simple sequential process with resources
Authors: Hong Liang , Jing JunFeng , Hou YiFan , Li Xun , Zhou Jian
Published: June 2016

The system of simple sequential processes with resources (S3PR) is a class of Petri nets that can model a typical class of resource allocation systems. This paper proposes a method to calculate the number of reachable states of an S3PR. First of all, an upper bound of reachable states of an S3PR can be obtained by combinatorics. The number of unreachable states may be counted in the upper bound because of the existence of shared resources. Hence, the next step is to subtract the number of unreachable states from the upper bound. Here, siphons with two resources derived from resource circuits are used to obtain the number of the unreachable states. The resulting number after subtracting the number of unreachable states from the upper bound is what we are looking for. Finally, example calculations and analyses are conducted to verify the effectiveness of the method. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Experimental investigation of a speed‐sensor‐less IM drive system under Inverter fault‐tolerant control
Authors: El‐Barbary Z. M. , Azazi H. Z.
Published: June 2016

This paper proposes an algorithm for fault tolerance of three‐phase, inverter‐fed, speed‐sensor‐less control of a three‐phase induction motor drive system. The fault tolerance of the inverter when one switch is open or one leg of six‐switch inverter is lost is considered. The control of the drive system is based on indirect rotor field‐oriented control theory. Also, the speed estimator is based on model reference adaptive system (using stator current and rotor flux as state variables for estimating the speed). The fault‐tolerant algorithm is able to adaptively change over from a six‐switch inverter to a four‐switch inverter topology when a fault occurs; also, it makes a smooth transition of the motor speed, torque, and current when changing over from a faulty condition to a new healthy status, which is four‐switch three‐phase inverter (FSTPI) topology; thus, the six‐switch three‐phase inverter (SSTPI) topology (pre‐fault status) is almost retained for the medium‐power range of induction motor applications. The proposed algorithm is simulated by using the MATLAB/SIMULINK package. Also, the proposed control system is tested experimentally using a digital signal processor (DSP1104). The obtained results from the simulation model and experimental system demonstrate the performance enhancement and good validity of the fault‐tolerance control for the speed‐sensor‐less induction motor drive system. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Analysis of water quality in Miharu dam reservoir, Japan, using UAV data
Authors: Kageyama Yoichi , Takahashi Junsuke , Nishida Makoto , Kobori Bunyuu , Nagamoto Daisuke
Published: June 2016

This letter reports on the water quality conditions of the Miharu Dam Reservoir. The water quality conditions appear in near‐infrared (NIR) data collected by an unmanned aerial vehicle (UAV). Because blue‐green algae occur in summer, the water quality of the small lake will be significantly worse at that time. On the basis of the experimental results for data from the months of July and August obtained using a fuzzy regression model, it is found that the UAV data is useful in assessing the water quality conditions in Lake Sakurako, and that the NIR data is effective in estimating the water surface conditions of the lake, especially caused by the occurrence of blue‐green algae. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Fetal cardiac axis in tetralogy of Fallot: associations with prenatal findings, genetic anomalies and postnatal outcome
Authors: Zhao Y. , Edington S. , Fleenor J. , Sinkovskaya E. , Porche L. , Abuhamad A.
Published: June 2016

Objective

To compare prenatal findings, associated genetic anomalies and postnatal outcome in fetuses with tetralogy of Fallot (TOF) with normal cardiac axis (CAx) and those with abnormal CAx.

Methods

In this retrospective cohort study, 85 cases diagnosed with TOF by prenatal ultrasound at our clinic between 2005 and 2015 were reviewed. Follow‐up ultrasound and postnatal outcome were available for 68 cases. One case complicated with absent pulmonary valve syndrome and a further seven cases diagnosed postnatally with anomalies other than TOF were excluded from the study. The remaining 60 cases of postnatally confirmed TOF were divided according to CAx into two groups: those with normal CAx (n = 33) and those with abnormal CAx (n = 27). CAx was defined as the angle between the interventricular septum and midline of the fetal thorax at the level of the four‐chamber view. CAx > 65° or < 25° was considered abnormal. Prenatal sonographic findings, associated genetic anomalies and postnatal outcome were compared between the two groups.

Results

Fetuses with TOF and abnormal CAx were more likely to have pulmonary atresia (40.7% vs 15.2%; P = 0.026) and right‐sided aortic arch (48.1% vs 21.2%; P = 0.028) than those with normal CAx. Postnatal death occurred in 30.4% of infants with abnormal CAx vs 6.5% with normal CAx (P = 0.028). Incidence of tested genetic anomalies was similar between the two groups.

Conclusion

In fetuses with TOF, abnormal CAx is associated with the presence of pulmonary atresia, right‐sided aortic arch and a higher risk of postnatal death. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.
The Prognostic Value of Preoperative Neutrophil‐to‐Lymphocyte Ratio in Colorectal Cancer
Authors: Kubo Hidemasa , Murayama Yasutoshi , Arita Tomohiro , Kuriu Yoshiaki , Nakanishi Masayoshi , Otsuji Eigo
Published: June 2016

Background

The prognostic value of the neutrophil‐to‐lymphocyte ratio (NLR) has been reported in several cancers included colorectal cancer; however, it is not clear if there is an association between NLR and cancer‐specific survival in colorectal cancer. And the optimal cut‐off value is controversial. This study was designed to assess the prognostic value of preoperative NLR in colorectal cancer patients.

Methods

Total 823 consecutive patients who underwent surgery for all stages of colorectal cancer in our hospital between January 2006 and December 2011 were included in the study. Preoperative NLR was calculated from their hospital records.

Results

Using the receiver‐operating characteristic curve, we found that the optimal preoperative NLR cut‐off value that was strongly associated with cancer‐specific survival was 2.1. Using this value, 505 patients were identified as having high NLR (≥2.1) and 397 patients were identified as having low NLR (<2.1). High NLR was associated with preoperative serum albumin values <4.0 g/dl (p < 0.001), positive preoperative serum C‐reactive protein (CRP; p < 0.001), preoperative carcinoembryonic antigen (CEA) values ≥5.0 ng/dl (p = 0.003), and stage progression (p = 0.002). Cox proportional hazard analyses identified preoperative high NLR as an independent poor prognostic factor (p = 0.020, HR 1.66 (95 % CI: 1.08–2.63)). When comparing stage of disease, preoperative high‐NLR patients with Stage III disease (p = 0.024) and Stage IV disease (p = 0.036) had significantly poorer prognoses.

Conclusions

In this study, we have demonstrated that preoperative NLR ≥2.1 was a prognostic indicator for cancer‐specific survival of colorectal cancer patients.
Mid‐Term Remission of Type 2 Diabetes Mellitus After Laparoscopic Roux En‐Y Gastric Bypass
Authors: Vasas Peter , Al‐Khyatt Waleed , Idris Iskandar , Leeder Paul C. , Awan Altaf K. , Awad Sherif , Ahmed Javed
Published: June 2016

Background

Laparoscopic Roux en‐Y gastric bypass (LRYGB) is an established therapeutic modality for type 2 diabetes mellitus (T2DM). However, there is paucity of data on the outcomes of LRYGB on T2DM beyond 2 years. This study aimed to examine the medium‐term effects of LRYGB on T2DM and determine the predictors of T2DM resolution.

Methods

Prospective data were collected for all consecutive LRYGB performed from September 2009 to November 2010. The American Diabetes Association guidelines were used to define complete (CR) or partial (PR) remission of diabetes. Diabetes status was considered improved when there was >50 % reduction in the dose of medications or when glycaemic control was achieved after stopping insulin. The effects of baseline characteristics, diabetes data and weight loss data at 4 years on T2DM remission were studied.

Results

Forty‐six patients with T2DM underwent LRYGB with mean ± SD age and body mass index (BMI) of 48.6 ± 9.6 years and 50.4 ± 6.5 kg/m2, respectively. Median (IQR, interquartile range) duration of T2DM preoperatively was 60 (36–126) months. Median (IQR) follow‐up was 52 (50–57) months. T2DM remission was achieved in 64 % of patients (44 % CR, 20 % PR), and a further 28 % of patients had improvement in their diabetes status. Multivariate analyses demonstrated significant excess weight loss (EWL) [P = 0.008] and lower BMI [P = 0.04] at 4 years to be the only independent predictors of T2DM medium‐term outcomes.

Conclusion

The medium‐term effects of LRYGB on T2DM remission/improvement were maintained in 92 % of patients. EWL and lower BMI at 4 years were independent predictors of T2DM remission.
F.05 Characterization of NBCA glue polymerization for embolization of brain AVM’s
Authors: Wang BH , Pelz D , Lee D , Boulton MR , Lownie SP
Published: June 2016

Background: Brain arteriovenous malformations (AVM’s) are abnormal connections between arteries and veins. Endovascular glue embolization with N-butyl cyanoacrylate (NBCA) is an accepted form of treatment, with most complications related to timing of polymerization. Current literature reports a wide range of polymerization times with large discrepancies between in-vivo and in-vitro results. Methods: Polymerization time was measured for mixtures of lipiodol/NBCA of 50/50, 60/40, 70/30. The influence of pH, temperature and presence of biological catalysts on polymerization rate was investigated in-vivo using submerged droplet tests. PVA-C, silicone and endothelium surfaces were compared and contact angles were measured to assess physical interaction with NBCA. High-speed video of glue injection through a microcatheter was captured to characterize coaxial flow. Results: Polymerization rate increases with pH and temperature. A hydrophilic substrate such as PVA-C provides surface properties that are most similar to endothelium. Endothelium provides a catalytic surface that increases the rate of polymerization. Blood products further increase the polymerization rate with RBC’s providing almost instantaneous polymerization of NBCA upon contact. Characterization of coaxial flow shows dripping to jetting transition with significant wall effect. Conclusions: We have successfully deconstructed and characterized the dynamic behavior of NBCA embolization. A refined understanding of NBCA behavior could help reduce embolization-related complications.
F.07 Reducing ventricular shunt malfunction in the adult patient
Authors: Hamilton MG , Urbaneja G , Hockley A , Isaacs A
Published: June 2016

Background: Treatment of adult patients with hydrocephalus is often undertaken with a ventriculoperitoneal shunt (VPS). Failure rates have been reported as high as 50% in the first year. Methods: A Quality Improvement (QI) model was used to evaluate and modify VPS-insertion techniques to improve outcome. Malfunction was defined as a change in neurological shunt-related function with correlated diagnostic imaging studies. Prospectively collected data from 2012-2015 was reviewed. Results: 146 patients underwent a new VPS insertion. Diagnoses were: normal pressure hydrocephalus 101 patients, acquired hydrocephalus 28 patients and chronic-congenital hydrocephalus 17 patients. 103 patients had traditional insertion of a ventricular catheter using surface landmarks with 2 catheter misplacements requiring surgery. Image guidance with electromagnetic tracking was instituted with 0 catheter misplacements in 43 consecutive patients. 121 patients had traditional minilaparotomy/trocar placement of the peritoneal catheter with 59/121 (49%) experiencing shunt malfunction and 35/59 (59%) experiencing a second malfunction requiring surgery. Laparoscopic insertion of the peritoneal catheter was instituted in 25 consecutive patients with 3 (12%) distal obstructions. Laparoscopy was also used in 13 patients undergoing VPS revision with 2 (15%) experiencing subsequent malfunction. Conclusions: Changes to standard VPS surgical treatment including the addition of image-guidance and laparoscopic surgical techniques were associated with a significant decrease in shunt malfunction requiring surgery.
P.003 Health-related quality of life (HRQOL) for genetically determined leukoencephalopathy patients and their families
Authors: Mirchi A , Pelletier F , Tran LT , Pizzino A , Dilenge M , Braverman N , Vanderver A , Roncarolo F , Bernard G
Published: June 2016

Background: Genetic leukoencephalopathies are a group of neurodegenerative diseases imposing a great burden on patients and families. There is no previous systematic study looking at the impacts of these diseases. Methods: HRQOL was assessed using the Pediatric Quality of Life Inventory (PedsQL) model. A total of 24 patients with genetically determined leukoencephalopathies and their family members completed the PedsQL questionnaires. Detailed clinical assessments were performed at the time the questionnaires were filled. HRQOL results were correlated with the severity of the clinical features and the presence vs. absence of a definitive molecular diagnosis. Results: Preliminary results show lower PedsQL total scores for patients without compared to with a molecular diagnosis. Emotional and physical functioning scores were significantly impaired in patients without a molecular diagnosis. Lower total scores were obtained for patients who presented more severe clinical features such as lost ambulatory functions and dysphagia. Conclusions: Overall, our preliminary results indicate that patients without a molecular diagnosis have an impaired HRQOL and that more severely affected patients have a poorer HRQOL. Further analyses and studies on a larger population of patients in a prospective fashion are required to assess the burden of these diseases and identify potential modifiable factors.
P.004 Endocrine and growth abnormalities in 4H leukodystrophy patients with a molecular diagnosis
Authors: Pelletier F , Mirchi A , Cayami FK , Tran LT , Ulrick N , Polychronakos C , Vanderver A , Wolf NI , Bernard G
Published: June 2016

Background: 4H or POLR3-related leukodystrophy is an autosomal recessive disorder characterized by hypomyelination, hypodontia and hypogonadotropic hypogonadism caused by mutations in POLR3A, POLR3B and POLR1C. The endocrine abnormalities have never been systematically studied. Methods: A cross sectional international multicenter study was performed and the following variables were assessed: weight, height, head circumference, pubertal history, hormone levels and neurological and non-neurological features. Data was analyzed to determine whether there was a correlation between the presence of endocrine abnormalities and mutations in a specific gene and/or the presence of specific symptoms such as other non-neurological symptoms. Results: Data was collected on 156 patients. Endocrine data were available for 144 patients. The most common endocrine abnormalities seen in this cohort were short stature (54/90 patients (60%)) and delayed puberty (53/70 patients (76%)). 13 of the 58 patients tested (22%) had abnormal thyroid function. Patients with POLR3A mutations were more likely to have endocrine abnormalities. Conclusions: Our results confirm that the most common endocrine features in 4H leukodystrophy are short stature and pubertal abnormalities. However, the other potential endocrine abnormalities are typically under-investigated in this patient population. A prospective study is required to investigate the extent and severity of the endocrine abnormalities in 4H leukodystrophy.
P.013 Conflicts of interest in neurosurgical research - comparing voluntary physician disclosure to mandatory company data
Authors: McDonald PJ , Shon ER , Kulkarni AV
Published: June 2016

Background: Industry involvement in neurosurgical research is common, creating financial conflicts of interest (COIs). Most journals require voluntary disclosure of financial COIs. In 2013, the Sunshine Act (SA) was passed in the US, mandating industry disclosure of all payments to physicians. The accuracy of voluntary disclosure can now be determined by comparing voluntary author disclosure with industry data. Methods: We reviewed disclosure statements and calculated rates of voluntary disclosure in major neurosurgical journals before (2011) and after (2013) the Sunshine Act to determine if voluntary disclosure increased after its implementation. We then determined the accuracy of voluntary disclosure in 2013, comparing voluntary disclosure with industry disclosure on the Open Payments Database (OPD). Mean, median and range of industry payments to neurosurgeons were calculated Results: Voluntary disclosure significantly increased in JNS-Spine only (10.7% to 35.4%,p<0.001) after implementation of the SA. The average rate of non-disclosure in all journals studied was 38.3% (Range 33.8%-42.2%)

$32,598,522.97 of industry payments were provided to 656 authors in the five-month period studied (Average $49,692.87/author) Conclusions: Voluntary COI disclosure in JNS- Spine increased after implementation of the Sunshine Act. Industry payments to physicians publishing in neurosurgery journals are common and rates of non-disclosure of COIs are high. The ethical implications of COIs and non-disclosure are discussed.
P.049 Medically refractory longitudinally extensive transverse myelitis successfully treated with cyclophosphamide induction
Authors: Baxter LJ , Chen S , Burton JM
Published: June 2016

Background: Longitudinally extensive transverse myelitis (LETM) is a demyelinating condition that is associated with diseases such as neuromyelitis optica spectrum disorder (NMOSD), acute disseminated encephalomyelitis, collagen vascular disease, or can be idiopathic. LETM can be severe enough to cause quadraparesis, marked sensory dysfunction, and respiratory failure. Rarely, these patients are unresponsive to conventional immune therapy. Methods: We report two cases of severe LETM with acute development of quadraparesis and respiratory failure requiring intensive care admission and failure to respond to high-dose corticosteroids, plasma exchange, IVIg and rituximab. Disease cessation and ultimately, significant recovery, was achieved after an 8-day cyclophosphamide induction. Results: A 21 yo female with antibody positive NMOSD and a 19 yo male with idiopathic LETM remained quadraparetic and ventilator dependent with active MRIs despite multiple courses of intravenous methylprednisolone, plasma exchanges, and in the NMOSD patient, IVIg and a 4-week course of rituximab. Both patients ultimately improved significantly and are now ambulatory with subsequent cyclophosphamide induction. Conclusions: In patients with severe LETM of presumed immune origin, who fail to respond to corticosteroids and plasma exchange, cyclophosphamide induction should be considered. This agent provides a more robust immunosuppressive response and can be induced rapidly. Cyclophosphamide effects and supportive evidence are further discussed.
P.069 The predictive factors of electroencephalograms with epileptiform activity in psychiatric patients
Authors: Dash C , Mischuk BJ , Almubarak S , Moien-Afshari F
Published: June 2016

Background: Psychiatrists commonly use electroencephalogram (EEG) to rule out epilepsy as a cause of psychiatric symptoms. A large number of these studies are normal. Our study aims to identify the predictive factors of an EEG with epileptiform activity in these patients. Methods: We performed a retrospective study of the EEG results and chart reviews of the 208 psychiatric patients at Royal University Hospital in Saskatoon, Saskatchewan from 2013-2015. The EEG results were correlated with several factors known to increase the probability of an abnormal recording including history of seizures, previously abnormal EEGs, imaging abnormalities, medications known to cause epileptiform discharges, electroconvulsive therapy, prematurity, brain infection, childhood febrile seizures, head trauma, and family history. Results: Of the 208 EEGs performed, 176 (84%) were normal (77%) or essentially normal (7%). Epileptiform activity was found in 13 EEGs (6.3%), of which 9 (4.3%) had a previous EEG with epileptiform activity. Focal slowing appeared in 12 EEGs (5.8%), two of which had previous abnormal EEGs. Generalized slowing was found in 7 EEGs (3.4%). Conclusions: We conclude that the majority of EEGs in patients with psychiatric manifestations are normal. The most predictive factor for epileptiform activity in this population is a previous EEG with epileptiform discharges. Other predictive factors are under review.
P.073 Transient osteoporosis of the hip during pregnancy associated with EMG signs of acute regional denervation
Authors: Ziller MG , Stein MA , Sygal V
Published: June 2016

Background: Transient osteoporosis is an infrequent musculoskeletal condition most often seen in middle-aged males, but can rarely present during late pregnancy in females. Patients present with sudden onset of severe joint pain. MRI typically shows T2 hypersignals and bone marrow edema. Abnormal neurophysiological findings have only rarely been described in the literature. Methods: Case report Results: A 35-year old patient presented at 34 weeks of pregnancy with acute onset of right hip and leg pain. MRI showed marked T2 hypersignals in the head of the femur with distal extension and bone marrow edema pathognomonic of transient osteoporosis. Neurophysiological studies showed normal nerve conductions of the lower extremities, but fibrillation potentials and positive sharp waves were found acutely in proximal muscles of the affected extremity and not limited to a single nerve territory. Inflammatory markers were unremarkable. Treatment was conservative with rest and reduction of weight bearing and pain resolved in the hip, but recurred in the ipsilateral knee several months after delivery suggesting evolution toward regional migratory osteoporosis. Conclusions: Transient osteoporosis of the hip may be associated with EMG signs of denervation that could suggest a contributing neurogenic mechanism. Their prevalence may be underestimated and we suggest considering serial EMG studies in its investigation.
P.083 Trigeminal neuralgia caused by an intra-axial glioma in a child: first surgical case report and systematic review
Authors: Bokhari R , Baeesa S , Sabbagh A , Atkinson J , Dudley R , Farmer J
Published: June 2016

Background: Trigeminal neuralgia (TGN) is usually caused by arterial compression of the trigeminal nerve. There are very few cases caused by intra-axial brainstem masses. Little information is therefore available regarding the response to incomplete resection of offending lesions. We present one such case, and systematically review the published in the literature. Methods: Case report and systematic review of MEDLINE and EMBASE Results: Case report: A seven year-old girl is referred with typical TGN pain. MRI revealed a cervicomedullary tumor with no abnormalities of the pons or trigeminal nerve. Subtotal resection under neurophysiologic monitoring was achieved, leaving a small residual attached near the expected location of the trigeminal spinal nucleus and tract.Patient recovered well with resolution of her TGN pain. She is asymptomatic seven years post-operatively. Literature Review: We found no other published cases in children or secondary to gliomas. Among reviewed cases, only two underwent surgery. Both were adults with brainstem cavernomas and both reported substantial improvement despite incomplete resection. Conclusions: Our case as well as literature review both show that surgical resection is beneficial in such cases and, even if subtotal, can result in substantial pain relief. This suggests intra-axial compression of the trigeminal spinal nucleus and tract as the possible cause of TGN pain in such cases.
P.107 Primary clear cell chondrosarcoma of the thoracic spine
Authors: Mcgregor S , Kurdi M , Hammond R , Siddiqi F , Wehrli B
Published: June 2016

Background: Clear cell chondrosarcoma (CCC) is a rare, low-grade, subtype of chondrosarcoma. It arises most commonly in the epiphyses of the certain longbones. Spinal involvement is extremely rare, but when present it most frequently involves the thoracic spine. Complete surgical resection is the best curative treatment, with radiation therapy being a consideration for inoperable tumours. Methods: We report a case of a 70-year-old gentleman with CCC of the T7-8 thoracic spine. Gross en-bloc spondylectomy of the T6-8 vertebral bodies with expandable cage reconstruction and T3-11 instrumented fusion were performed. Results: Histological examination revealed a cellular neoplasm composed of well-defined, round to oval cells with abundant clear cytoplasm embedded in a loose cartilaginous matrix with large numbers of admixed osteoclast-type giant cells and scattered bone trabeculae between the lesional cells. The patient experienced significant improvement in neurological function and was discharged from hospital in stable condition seven days after surgery. Conclusions: CCC is a rare variant of chondrosarcoma that rarely involves the osseous spine. In this location, treatment may be challenging given the presence of spinal cord and nerve roots. Given the lack of effective chemotherapy and radiation therapy for CCC, en-bloc resection of CCC involving the spine should be considered.
P.118 An experience with combined cerebral oximetry and stump pressure measurement to guide shunt insertion during carotid endarterectomy
Authors: Kesarwani R , Findlay M
Published: June 2016

Background: Cross-clamp ischemia during carotid endarterectomy (CEA) can cause perioperative stroke. Selectively shunting patients based on intraoperative monitoring modalities that assess risk for ischemia can reduce the occurrence of immediate stroke. An experience with combined cerebral oximetry and stump pressure measurement to direct selective shunting is presented here. Methods: Study comparing intraoperative monitoring data, the decision to shunt, and presence of immediate post-operative deficits. Patients were shunted if either cerebral oxygen saturation dropped by more than 10% by cerebral oximetry, or stump pressure during cross-clamping was less than 40 mmHg. Cross-clamp ischemia was determined by the presence of ipsilateral neurological deficit upon awakening. Results: 245 patients were included in this study. 22% were shunted. Patients who were not shunted were significantly more likely to have collateral blood flow detected on angiography. Immediate post-operative stroke was not encountered in any of the patients included in the study. One patient who met shunting criteria but was excluded since he could not have a shunt inserted due to difficult anatomy did suffer stroke. Conclusions: With the dual-monitoring criteria presented here, 22% of patients were shunted. With the exception of one patient who could not have a shunt placed, no immediate post-operative stroke was encountered.
P.121 Open surgical trans-venous Onyx embolization of Rolandic arteriovenous malformations: case report and review of literature
Authors: Wang BH , Pelz D , Pandey S , Boulton MR , Lownie SP
Published: June 2016

Background: Premature occlusion of draining veins during surgical resection of arteriovenous malformations (AVM’s) can lead to disastrous consequences. Interestingly, some authors have recently demonstrated effective endovascular trans-venous Onyx embolization of select AVM’s. Methods: Case report Results: A 71-year old female presented to the hospital with sudden onset right sided weakness and sensory change. Investigations revealed right fronto-parietal ICH secondary to a parasagittal Rolandic AVM with arterial supply from ACA and MCA branches. Drainage occurs via a single large cortical vein to the superior sagittal sinus. Partial intra-arterial embolization was initially performed. Surgical resection of the remaining nidus was deemed high risk. A craniotomy was performed and the large cortical draining vein was cannulated with a 4Fr micro-puncture system under direct visualization. A DMSO compatible micro-catheter was navigated retrograde close to the nidus. The draining vein was occluded using a surgical clip, and Onyx was immediately injected. Retrograde complete embolization of the AVM was observed. A total of 3ml of Onyx was injected, and the catheter was left in-situ. Patient was discharge 2 weeks later with minimal deficits. Conclusions: Open trans-venous embolization is a viable option for select AVM’s with a single draining vein and are not favorable candidates for trans-arterial embolization, surgery or radiation.
P.125 A severe case of Menkes: an infant’s presentation with intraventricular hemorrhage
Authors: Szelemej PA , Stevic I , Del Bigio M , Mhanni A , Hartley J , Greenberg C , Frosk P , Seargeant L
Published: June 2016

Background: Menkes disease is a rare, X-linked recessive disorder of the ATP7A gene, a copper transporter; resulting in systemic copper deficiency. The deficient function of copper-dependent enzymes manifests clinically with failure to thrive, seizures, hypotonia, coarse hair, connective tissue abnormalities, and neurodegeneration. Cerebral arteries are often elongated, tortuous, and fragile. Methods: This case report was prepared using the patient’s hospital chart, and a review of the literature undertaken using PubMed. Our case was subsequently compared and contrasted to known Menkes’ literature. Results: We present the case of a 2 month old male with Menkes disease who presented with new seizure onset in the setting of a Grade III intraventricular hemorrhage with hydrocephalus. He deteriorated into status epilepticus, and palliative care was instituted. On autopsy, pronounced tortuosity of his cerebral vasculature was noted, as well as a bilaterally cystic brain with an organizing hemorrhage on the ventral surface of the brainstem. Conclusions: Although Menkes disease often presents with seizures, neurologic deterioration, and abnormal cerebral vasculature; the quick demise subsequent to an intraventricular hemorrhage is somewhat unusual and discussed.
P.134 Spinal epidural abscess associated with septic facet joints-one center experience
Authors: Meguro K , Pirlot B , Ellchuk T , Ahmad U
Published: June 2016

Background: Infection to the facet joints has been reported sporadically but the significance of this type of infection has not been clarified. In our study on spine infection, we identified the cases of spinal epidural abscess with septic joints and was able to compare to cases of epidural abscess with discitis and osteomyelitis. Methods: Between 2007 and 2014, we experienced 176 cases of spine infection including discitis, osteomyelitis and epidural abscess. Retrospective review of the clinical data and radiological findings was performed. Among 176 cases, 80 patients had epidural abscess. They were divided to two groups, one with septic joint and the other with discitis and osteomyelitis. Results: 23 patients were found to have septic joints with epidural abscess based on the MRI findings. Mean age was 45.5. 15 of 23 patients (65%) required surgery and all treated with laminectomy. 78% had a good neurological outcome.

57 patients had epidural abscess with discitis and osteomyelitis. Mean age was 54. 51% required surgery. Only 62 % was treated with laminectomy alone. Good neurological outcome was seen in 67% of the patients. Conclusions: Infected facet joints are not as rare as generally believed. The patients with septic joints are younger. Surgery was done more often and laminectomy provided better neurological outcome
B.05 Optimizing IVIg utilization for neuromuscular disease in BC: high user project
Authors: Chapman KM , Mosewich R , Trewern T , Li C , Gibson G
Published: June 2016

Background: In British Columbia, neuromuscular disease accounts for 31% of IVIg use, at a cost of $10.1 M. In addition to the new screening pathway, the BC Neuromuscular IVIg Program developed the Chronic High User Project to identify areas for improvement in utilization. Methods: Utilizing CTR data, all patients on IVIg maintenance therapy for approved neuromuscular conditions between April 1, 2013 and March 31, 2014 were identified. Patients receiving higher than usual IVIG treatments (CIDP and MG >1110 grams/year, MMNCB > 1400 grams/year) were evaluated. Following panel review, utilization data was compared with a second cohort (2014 to 2015) to determine impact. Following review, appropriateness of treatment was determined by consensus from a 3-member panel, and recommendations were made. Results: Of 377 patients, 38 “High Users” were identified. 29 cases were determined to be appropriate; 9 were not. There was a reduction in mean grams/episode in CIDP (1135g to 990g) and MG (1099 g to 1022g) between cohorts. The mean grams/episode for MMNCB did not change. Conclusions: In specific cases, the IVIg High User Program identified patients in whom the treatment could be optimized. However, the vast majority of use of IVIg for Neuromuscular Disease in BC is appropriate, including in patients requiring higher that “usual” doses.
B.06: Two definite sudden unexpected deaths in epilepsy in a family with a DEPDC5 mutation
Authors: Nascimento FA , Borlot F , Cossette P , Minassian B , Andrade D
Published: June 2016

Background:DEPDC5 gene, mapped to 22q12.2-q12.3, has been associated with a variety of familial epilepsies, including FFEVF, autosomal dominant nocturnal frontal lobe epilepsy, and familial TLE. Notably, DEPDC5 has never been linked to increased risk of sudden unexpected death in epilepsy (SUDEP). Methods: Cases review. Results: We studied a three-generation, non-consanguineous, French-Canadian family with nine clinically affected individuals. The index case is a 39-year-old man who started having seizures (as 2rily GTCS) at the age of 13 years. EEGs showed interictal discharges over the right anterior-temporal region. Brain MRI was unremarkable. Two individuals in this family suffered definite autopsy-confirmed SUDEP, at the ages of 58 and 50 years, respectively. Overall, seizure-history in this family can be summarized by an onset before reaching adulthood followed by subsequent progressive decrease in seizure frequency. Seizures were predominantly nocturnal 2rily GTC. Genetic analysis revealed a pathogenic heterozygous variant in the DEDPC5 gene (p.Gln216, c.646C>T), which results in a premature stop codon, in all affected family members plus on heatlhy relative. Importantly, all the subjects were cognitively intact, and there was no history of cardiac symptomatology/cardiovascular risk factor. Conclusions: The finding in this family suggests that DEPDC5 mutations may be a risk factor for SUDEP.
D.04 Validating StatNet EEG as a reliable and effective tool in the Diagnosis of Non-Convulsive Status Epilepticus after hours
Authors: Voll AR , Dash D , Sutherland W , Hernandez-Ronquillo L , Tellez-Zenteno JF , Moien-Afshari F
Published: June 2016

Background: NCSE dramatically increases morbidity and mortality. It is clinically subtle, which makes it difficult to diagnose without EEG. StatNet EEG provides a quick alternative to conventional EEG, which is often unavailable after hours. Methods: Each patient received a StatNet EEG by a neurology resident and a conventional EEG by an EEG technologist. Blinded studies were compared for delay between the studies, setup time, artifact, and abnormality detection using conventional EEG as controls. Nonparametric Mann-Whitney two-sample T-test was used. Results are expressed in mean minutes +/- SD. Kappa score assessed inter-observer reliability. Results: 19 patients were collected. Two StatNet EEGs were not interpretable and excluded. The mean delay between studies was 26h53min. Electrode placement is significantly shorter: 13:14±5:24 StatNet EEG vs 18:07±5:35 conventional EEG (p=0.02).

Conclusions: There is high inter-rater reliability between the conventional and StatNet EEG groups (table 1) demonstrating that StatNet is a reliable and effective tool, aiding in early recognition and management of NCSE.
D.06 Insular involvement in intractable epilepsy: results of invasive EEG data
Authors: Ranjan M , Starreveld Y , Bello-Espinosa L , Wiebe S , Singh S , Hader WJ
Published: June 2016

Background: Exploration of the insular cortex is now commonly considered in patients with refractory epilepsy requiring invasive EEG investigations. The safety and yield of routine insular exploration is uncertain. Methods: All patients (pediatric and adult) who had invasive EEG (iEEG) with insular depth electrode placement, either through SEEG or open implantation, were reviewed. Ictal insular involvement was characterized as primary, secondary or not involved. Results of insular resections were recorded. Results: A total of 173 patients had iEEG of which 26 included insular electrodes (SEEG-18, Open - 8). No complications of placement were identified. Insular involvement was seen in 20 (76%) patients. Primary ictal involvement was identified in 9 (33 %) patients, while secondary spread was noted in 11 (42 %) patients. Six patients went on to have resections including the insular cortex of which 5 patients achieved good seizure control (Engle class I/II). Conclusions: Insular depth electrode placement is a safe and effective adjunct to invasive EEG investigations. Ictal involvement of the insular cortex was commonly identified in our series leading to inclusion of the insula in cortical resections with good seizure control, which may not have been considered without iEEG evidence.
D.10 Acute flaccid paralysis in Canadian youth, 1996 to 2014
Authors: Rotondo J , Desai S , Beaulieu M , Booth TF
Published: June 2016

Background: Acute flaccid paralysis (AFP) is notifiable in Canada with a differential diagnosis that includes a number of conditions. This analysis describes the epidemiology of AFP in Canadian youth less than 15 years old. Methods: Monthly active surveillance for AFP was conducted as part of the Canadian AFP Surveillance System. Results: From 1996 to 2014, 850 cases of AFP were reported, representing an average annual crude incidence rate of 0.77 cases per 100,000 youth less than 15 years old. The mean age of cases was 6.8 years (median 5.9 years). Nine percent had an abnormal neurological history and 53% had an acute respiratory illness within 30 days of onset. Fever occurred in 23% of cases, 96% experienced bilateral weakness, 21% had respiratory muscle involvement, and 26% had cranial nerve involvement. The average hospital length of stay was 13.5 days. The most common diagnoses were Guillain-Barré Syndrome (GBS) or a variant (70%), and transverse myelitis (TM, 14%). At the time of the initial report, 14% had fully recovered. Conclusions: Our AFP surveillance system provides a baseline for AFP and its causes in the Canadian paediatric population. While rare, AFP is associated with severe morbidity in youth. GBS and TM were the most common diagnoses.
A Green’s function approach to the rapid prediction of thermoacoustic instabilities in combustors
Authors: Bigongiari Alessandra , Heckl Maria A.
Published: June 2016

The prediction of thermoacoustic instabilities is fundamental for combustion systems such as domestic burners and industrial gas turbine engines. High-amplitude pressure oscillations cause thermal and mechanical stress to the equipment, leading to premature wear or even critical damage. In this paper we present a new approach to produce nonlinear (i.e. amplitude-dependent) stability maps of a combustion system as a function of various parameters. Our approach is based on the tailored Green’s function of the combustion system, which we calculate analytically. To this end, we assume that the combustor is one-dimensional, and we describe its boundary conditions through reflection coefficients. The heat release is modelled by a generalised $n{\it\tau}$ law. This includes a direct-feedback term in addition to the usual time-lag term; moreover, its parameters (time lag, coupling coefficients) depend on the oscillation amplitude. The model provides new insight into the physical mechanism of the feedback between heat release rate and acoustic perturbations. It predicts the key nonlinear features of the thermoacoustic feedback, such as limit cycles, bistability and hysteresis. It also explains the frequency shift in the acoustic modes.