Although electromyography (EMG), electroencephalography (EEG) and evoked potential (EP) studies are common investigation tools for patients with neurologic illnesses, no formal data on the manpower supply in Canada exists. Because of the importance of these on training requirements and future planning, the purpose of this study was to establish a comprehensive profile of the human resources situation in clinical neurophysiological services across Canada.

A questionnaire was sent to all clinical neurophysiologists in Canada. To capture the maximal number of respondents, a total of three rounds of mail out were done. In addition, to obtain accurate demographic data on supporting technologists, a separate survey was also carried out by the Association of Electrophysiological Technologists of Canada.

Of the 450 clinical neurophysiologists identified and surveyed, the provincial response rate was 59±14% (mean±SD). Of these, the vast majority practiced in urban centres. There was substantial regional disparity in different provinces. While the wait time for most EEG and EP laboratories was less than six weeks, the wait time for EMG was substantially longer. With the age of the largest number of practitioners in their sixth decade, projected retirement over the next 15 years was 58%. The demographic distribution of the supporting technologists showed a similar trend.

In addition to considerable regional disparity and urban/rural divide, a large percentage of clinical neurophysiologists and supporting technologists planned to retire within the coming decade. To ensure secure and high standard services to Canadians, solutions to fill this void are urgently needed.

Superficial anastomotic veins (SAVs) have been studied extensively but little attention has been paid to clinical studies. The aim of this study is to provide variations in the drainage patterns of SAVs depending on the intraoperative findings.

A total of 251 craniotomies due to intractable temporal lobe epilepsy were performed between 1972 and 1987 at the Montreal Neurological Institute. The courses of the three largest SAVs including the vein of Trolard (VT), vein of Labbe (VL) and superficial Sylvian vein (SSV) were studied.

All three veins showed variable courses. The most common predominant vein was the combination of the VL + SSV. The VT and VL were frequently coursed at the level of the central vein and middle temporal vein, respectively. On the right hemisphere the SSV was the predominant type while the VL tended to be predominant on the left hemisphere. A combination of VL and SSV was predominant in patients with right and/or left hemispheric dominance.

The SAVs showed considerable variation in their courses and it is difficult to define an exact pattern although some courses showed constant directions. Attention should be paid not to damage these veins since in a considerable number of cases a single dominant vein may be responsible for draining a majority of the lateral surface of cerebral hemisphere.

Glucocorticoid treatment improves the speed of functional recovery of acute multiple sclerosis (MS) relapses but has not been shown to provide any long-term functional benefit. There is currently no convincing evidence that the clinical benefit is influenced by the route of administration or the dosage of glucocorticoid, or the particular glucocorticoid prescribed. Recent studies support similarities in the bioequivalence and in the clinical effect of high dose oral corticosteroids for MS relapses.

This survey aimed to determine the relapse treatment preferences of clinicians in Canadian MS clinics.

Members of the Canadian Network of MS Clinics are linked by an email server. A one page survey was distributed to the group to determine and report use of corticosteroids to manage MS relapses amongst Canadian MS specialists.

Fifty-one clinicians from 17 MS clinics were surveyed. 32 (63%) surveys were returned representing 16 clinics. Five doses are most commonly prescribed, usually without a taper. Three or four doses and the use of a corticosteroid taper, however, are not uncommon. Gastric cytoprotection and sedatives are often prescribed for use as needed.

This survey illustrates that when Canadian clinicians with expertise in managing MS treat MS relapses they choose high dose corticosteroids, either oral or IV. The results therefore represent Canadian practice as these clinicians provide direct patient care and influence care by community neurologists. Until evidence clearly identifies a superior practice all options should be available to clinicians and their patients.

As has been shown previously, S-100β levels in serum can be a useful predictor of brain damage after head trauma. This pilot study was designed to investigate whether urine samples, which are much easier to obtain, could be used for the same purpose instead of serum samples.

Ninety-six consecutive patients admitted with head trauma were recruited in the study. After exclusion of 54 patients, mostly because of significant additional trauma, S-100β levels were analyzed in serum and urine of 42 patients using a luminometric assay. A range for normal values was established based on samples from ten healthy volunteers.

S-100β serum levels increased proportional to the severity of the head trauma, as had been previously shown by several other groups. In many patients, initial increases in urine S-100β levels were seen later than in serum, after which the kinetics of S-100β levels in urine seemed to follow that established for serum levels. S-100β values in urine were on average about 54% lower in urine than in serum.

S-100β levels in urine obtained on admission to the hospital are not a good indicator for the extent of brain damage. However, urine S-100β levels obtained at later time points might be a useful indicator for the development of secondary brain injury.

Dural arteriovenous fistulae (DAVF) of the hypoglossal canal region are rare lesions. We describe three cases of DAVF of the hypoglossal canal presenting with ocular symptoms and discuss the endovascular management options.

Three consecutive patients with DAVF of the hypoglossal canal region presented with proptosis, chemosis and disturbances of extra-ocular mobility. Each patient was treated using a different endovascular approach, based on variations of the vascular access.

The cases and treatments are reviewed, with a literature review on the subject. Endovascular treatment, transvenous or trans-arterial was curative in all cases.

DAVF of the hypoglossal canal region can present with ocular manifestations very similar to DAVF of the cavernous sinus or carotid-cavernous fistulas. Endovascular treatment is usually feasible and effective, but an understanding of the vascular anatomy and pathophysiology of the disease are of utmost importance when planning the approach.

Dural arteriovenous fistulas are uncommon lesions in children, with traumatic lesions suspected to arise from incomplete arterial injury in proximity to a vein or draining sinus. Management of symptomatic acquired lesions requires evaluation of patient presentation, neurological status, and pathoanatomic configuration, with special consideration required for surgery secondary to failed endovascular technique.

A 12-year-old male sustained a bicycle fall causing a right temporo-parietal skull fracture associated with non-surgical right epidural hematoma and left contre-coup parietal contusion. Six-weeks later, he complained of a right temporal bruit with subsequent cerebral angiography demonstrating a dural-based fistula between the right middle meningeal artery and a dural vein draining into the sigmoid sinus.

Endovascular treatment of this lesion with glue embolization and coiling was unsuccessful, with angiographic illustration of previously unobserved collateral vessels and coils occupying the sigmoid sinus. A right temporo-parietal craniectomy was required to excise the dural-based fistula, followed by dural defect repair with bovine pericardium and subsequent cranioplasty. Six years later the patient remains neurologically intact with no headaches or bruit.

Dural arteriovenous fistula can uncommonly occur following traumatic injury in children. Partial injury to the middle mengineal artery may have established arterial communication with the draining vein that became ectatic and tortuous under high pressure. Failure of primary endovascular treatment may complicate secondary surgical intervention.

Chemoradiotherapy followed by monthly temozolomide (TMZ) is the standard of care for patients with glioblastoma multiforme (GBM). Case reports have identified GBM patients who experienced transient radiological deterioration after concurrent chemoradiotherapy which stabilized or resolved after additional cycles of adjuvant TMZ, a phenomenon known as radiographic pseudoprogression. Little is known about the natural history of radiographic pseudoprogression.

We retrospectively evaluated the incidence of radiographic pseudoprogression in a population-based cohort of GBM patients and determined its relationship with outcome and MGMT promoter methylation status.

Out of 43 evaluable patients, 25 (58%) exhibited radiographic progression on the first MRI after concurrent treatment. Twenty of these went on to receive adjuvant TMZ, and subsequent investigation demonstrated radiographic pseudoprogression in 10 cases (50%). Median survival (MS) was better in patients with pseudoprogression (MS 14.5 months) compared to those with true radiologic progression (MS 9.1 months, p=0.025). The MS of patients with pseudoprogression was similar to those who stabilized/responded during concurrent treatment (p=0.31). Neither the extent of the initial resection nor dexamethasone dosing was associated with pseudoprogression.

These data suggest that physicians should continue adjuvant TMZ in GBM patients when early MRI scans show evidence of progression following concurrent chemoradiotherapy, as up to 50% of these patients will experience radiologic stability or improvement in subsequent treatment cycles.

Clinical judgment, the ability to make appropriate decisions in uncertain situations, is central to neurological practice, but objective measures of clinical judgment in neurology trainees are lacking. The Script Concordance Test (SCT), based on script theory from cognitive psychology, uses authentic clinical scenarios to compare a trainee’s judgment skills with those of experts. The SCT has been validated in several medical disciplines, but has not been investigated in neurology.

We developed an Internet-based neurology SCT (NSCT) comprising 24 clinical scenarios with three to four questions each. The scenarios were designed to reflect the uncertainty of real-life clinical encounters in adult neurology. The questions explored aspects of the scenario in which several responses might be acceptable; trainees were asked to judge which response they considered to be best. Forty-one PGY1-PGY5 neurology residents and eight medical students from three North American neurology programs (McGill, Calgary, and Mayo Clinic) completed the NSCT. The responses of trainees to each question were compared with the aggregate responses of an expert panel of 16 attending neurologists.

The NSCT demonstrated good reliability (Cronbach alpha = 0.79). Neurology residents scored higher than medical students and lower than attending neurologists, supporting the test’s construct validity. Furthermore, NSCT scores discriminated between senior (PGY3-5) and junior residents (PGY1-2).

Our NSCT is a practical and reliable instrument, and our findings support its construct validity for assessing judgment in neurology trainees. The NSCT has potentially widespread applications as an evaluation tool, both in neurology training and for licensing examinations.

Studies on migraine in Nigeria are scanty while the disability associated with the disease has not been determined. We aimed at determining the lifetime prevalence of migraine and its associated disability among the students of a Nigerian university.

Using a multi-stage sampling method, undergraduates of Ambrose Alli University, Nigeria were screened with the International Headache Society (IHS) criteria. Those who satisfied the criteria for migraine were then assessed with the Migraine Disability Assessment questionnaire to ascertain the level of disability resulting from migraine in the three months preceding the study. Information was also obtained on the use of preventive and abortive medications.

Out of the 1513 respondents screened, 145 satisfied the IHS criteria for the diagnosis of migraine giving an overall lifetime prevalence of 9.6% (females 10.3%, males 8.9%, p>0.05). Migraine associated disability was little or none in 53.1% (males 55.2%, females 51.3%, p>0.05), mild in 10.3% (males 11.9%, females 9.0%, p>0.05), moderate in 20.7% (males 20.9%, females 20.5%, p>0.05) and severe in 15.9% (males 11.9%, females 19.2%, p>0.05). In spite of the fact that 53 (36.6%) of the migraineurs had moderate-severe disability, only 19/53 (35.8%) reported being on preventive treatment while none had ever used a triptan.

Prevalence of migraine among our respondents falls within the range reported from similar studies among university students outside Africa. In spite of the high disability associated with the disease, use of effective preventive and abortive therapies is very poor.

Dural sinus malformation (DSM) is a term used to describe congenital vascular malformations characterized by massive dilation of one or more dural sinuses: these dilatations are typically associated with arteriovenous shunts. Such malformations can present antenatally but their early natural history and anatomy is poorly defined.

We reviewed five years of autopsy experience and retrieved three primary vascular malformations of the fetal dural sinuses with ultrasound, magnetic resonance imaging (MRI) and post-mortem correlation.

Fetal ultrasound and MRI obtained between 19 and 23 weeks gestational age demonstrated in all cases dilation of the dural sinuses. In two cases vascular thromboses were present in either the dilated dural sinus (one of three) or the associated arteriovenous fistula (one of three). All cases were autopsied at 22-23 weeks gestational age. In one there was imaging and autopsy evidence of remodeling of the dural sinuses associated with a pial arteriovenous fistula. In two cases, no arteriovenous malformation was identified on initial imaging, but only became evident at autopsy. One case showed morphological overlap with vein of Galen aneurysmal malformation, with a midline arteriovenous shunt and vein of Galen ectasia. The other demonstrated a perisylvian dural arteriovenous fistula.

In utero thrombosis of feeding vascular malformations or of the dural sinus malformation may be prominent. The early in utero developmental trajectory of dural sinus malformation (DSM) is poorly defined and deserves further study.

Larger intracranial tumors require extended operating times and may be associated with increased perioperative complications. There are few reports describing the experience of resecting large meningiomas ≥5cm in a variety of locations. As a group, it remains largely unknown whether these relatively rare lesions are amenable to radical resection, and what factors influence their resectability.

Sixty-seven patients undergoing surgery for a large intracranial meningioma (≥5cm in the longest dimension) between 1998 and 2004 were retrospectively reviewed. The surgeries were performed at a single institution University of California at San Francisco. Predictors of resectability were assessed via multivariate logistical regression analysis.

Thirty-nine (58%) patients underwent gross total resection (GTR) (Simpson grades I/II). There were no cases of perioperative mortality. At last follow-up, symptoms improved in 39 (58%) patients, remained unchanged in 20 (30%), and were aggravated in 8 (12%). In the multivariate model for all large meningiomas, age>45 years [OR(95%CI);0.127 (0.026-0.616),p=0.01] and superior sagittal sinus involvement [OR(95%CI);0.160 (0.026-0.976),p=0.05] were negative predictors of GTR, while preoperative embolization [OR(95%CI);8.087(1.719-38.044),p=0.008] was positively associated with GTR. For only supratentorial meningiomas, superior sagittal sinus involvement [OR (95%CI);0.077 (0.010-0.571),p=0.01] and preoperative embolization [OR(95%CI);10.492(1.961-56.135),p=0.006] were independently associated with GTR.

This study evaluated a subset of large intracranial meningiomas ≥5cm. The results indicate that GTR can be achieved in the majority of cases with limited morbidity and mortality, where symptoms will likely improve and recurrences seldom occur. This study may provide useful insights for patients undergoing surgery for large intracranial meningiomas.

Carotid angioplasty and stenting is an accepted alternative treatment for severe restenosis following carotid endarterectomy. Balloons may not be required to effectively treat these lesions, given their altered histopathology compared to primary atherosclerotic plaque and tendency to be less calcified. Primary stenting using self-expanding stents alone may, therefore, be a safe and effective treatment for restenosis post-carotid endarterectomy.

We review our experience in the treatment of 12 patients with symptomatic severe restenosis following carotid endarterectomy with primary stent placement alone.

Self-expanding stent placement alone reduced the mean internal carotid artery stenosis from 85% to 29%. Average peak systolic velocity determined at the time of ultrasonography decreased from 480 cm/s at initial presentation to 154 cm/s post-stent deployment and further decreased to 104 cm/s at one year follow-up. The stented arteries remained widely patent with no evidence of restenosis. A single peri-procedural ipsilateral transient ischemic event occurred. There were no cerebral or cardiac ischemic events recorded at one year of follow-up.

In this series, primary stent placement without use of angioplasty balloons was a safe and effective treatment for symptomatic restenosis following carotid endarterectomy.

Trigeminal neuralgia (TN) often remains difficult to treat despite multiple available medications, and can severely impact on the quality of life of affected patients. Gamma knife radiosurgery has recently emerged as a minimally-invasive alternative to surgery for patients suffering from drug-resistant TN. The goal of this study was to report the short-term efficacy of gamma knife radiosurgery for TN and assess its impact on the quality of life of patients treated in the first 18 months of our experience.

Patients with medically-refractory TN or with unacceptable drug side effects were considered for radiosurgery. A maximum dose of 80 Gy was administered to the affected nerve using a single 4-mm isocenter. Follow-up assessments were made at 2, 4 and 6 months, with evaluation of pain relief, drug reduction and quality of life. Factors impacting treatment response were assessed using Cox regression analysis.

A total of 67 patients were treated. Significant pain relief was seen in 77.6% of patients, including 32.6% who became pain-free. Patients were able to discontinue all medications in 34.3% or reduce drug intake by more than 50% in an additional 28.4% of cases. No variable was found to predict pain relief although older age (>66 years) approached statistical significance. Sensory side effects were seen in 14.9% of patients. Quality of life improved in the majority of patients after radiosurgery.

Gamma knife radiosurgery is a safe and effective management alternative for trigeminal neuralgia, providing good or excellent pain relief and improvement in quality of life in the majority of patients with few side effects.

Cervical dystonia (CD) may be classified according to the underlying cause into primary or secondary CD. Previous exposure to neuroleptics is one of the main causes of adult-onset secondary dystonia. There are few reports that characterize the clinical features of primary CD and secondary neuroleptic-induced CD. Herein our aim was to investigate a series of patients with neuroleptic induced tardive CD and to describe their clinical and demographic features.

We retrospectively evaluated 20 patients with neuroleptic-induced tardive CD and compared clinical, demographic and therapeutic characteristics to another 77 patients with primary CD. All patients underwent Botulinum toxin type-A therapy.

We did not identify any relevant clinical and demographic characteristics in our group of patients that could be used to distinguish tardive and primary CD.

Patients with tardive CD presented demographic characteristics and disease course similar to those with primary CD.

Cortical dysplasias are rarely associated with vascular anomalies. They are usually associated with venous anomalies or in few cases with both arterial and venous anomalies.

Twenty-six year old female presented with history of headache showed cortical dysplasia associated with pure arterial dysplasia in the absence of any associated venous anomaly.

An abnormal arterial supply to or an abnormal venous drainage from the growing cortex may result in cortical rearrangements that eventually give rise to various neuronal migration anomalies.

Cortical mapping during awake surgery assesses intraoperative neurological change in response to electrical stimulation to provide direct information regarding the anatomical localization of the primary motor area (M1). The goal of the present study was to analyze the reliability of the identification of the precentral knob in the axial image of magnetic resonance imaging or functional MRI (fMRI) for the detection of M1.

Among patients with brain tumors within or near M1 in whom awake surgery was employed from April 2004 through March 2007, 14 cases were analyzed in which either the M1 or premotor area (PMA) was successfully detected by mapping during awake surgery.

The precentral knob was localized to the PMA in 4 cases and to M1 in 10 cases. By contrast, the gyrus activated by hand clenching in fMRI on the affected side at least partially corresponded to M1 in all cases, while those on the unaffected side corresponded to M1 in 12 of 12 cases.

These results indicate that the precentral knob corresponds to PMA as well as to M1, whereas the gyrus activated in fMRI corresponds to M1 on the affected and unaffected side.

Neurovascular compression (NVC) may cause cranial mononeuropathy but lacks a definitive diagnostic investigation. We hypothesized that the arterial pressure wave (APW) would interact at the neurovascular interface in NVC to inhibit transmission of transcranial magnetic stimulation (TMS) stimuli to affected muscles.

We report a novel neurophysiological method coupling cardiovascular physiology with TMS. The electrocardiogram (ECG) and arterial pressure wave (APW) were coupled to triggering of cortical TMS in a patient with NVC-induced spinal accessory (CNXI) mononeuropathy. Outcome measures included motor evoked potential (MEP) amplitudes and firing probabilities of normal and affected trapezieus (TPZ). Values at intervals in proximity to the APW (40/80/120/160ms) were compared to baseline (800ms) using ANOVA and student t-test.

Electrocardiogram triggered TMS of CNXI pathways with 100% reliability. MEP amplitudes were decreased in proximity to the APW, particularly at 120ms (0.21±0.04 mV versus 0.39±0.10mV, p=0.003). TPZ firing probabilities were similarly inhibited (43.8% versus 88.2%, p=0.009). No effect of APW proximity was observed on the unaffected side (p=0.868). Procedures were well tolerated.

Vascular compression causes CNXI mononeuropathy. Transcranial magnetic stimulation-cardiovascular coupling may evaluate neurovascular junction interactions and non-invasively diagnose NVC.