Over the past four years, West Nile virus (WNV) has become a significant health issue in North America. In 2002, WNV infection made its first appearance in the human population in Canada.

Patients who presented to the University Health Network and Mount Sinai Hospital in Toronto with neurological disease attributed to WNV infection were identified and followed by the neurology service. Clinical features and results of laboratory, electrodiagnostic, radiological and pathological studies are presented.

In August and September 2002, 26 patients were admitted with WNV infection; 14 presented with neurological illness. Encephalitis was the most common presentation (11 patients). Eleven patients developed neuromuscular disease; two at presentation and nine after encephalitis. While the majority had a motor process that localized to the anterior horn cell and/or motor neuron, two patients had evidence of a demyelinating neuropathy and one a sensorimotor axonal neuropathy. Less common manifestations included rhombencephalitis, ataxia, myelopathy and parkinsonism. Death occurred in four patients; two > 75 years of age, and two who were immunocompromised.

The most common neurological manifestation of WNV infection was encephalitis with subsequent neuromuscular involvement. The diversity of clinical and pathological findings, however, suggests widespread involvement of the central and peripheral nervous system. A poorer prognosis for neurological recovery and overall survival was seen in older and immunocompromised patients.

To assess the utility of a bedside measure of sensation (the Vibration Quantitation Scale (VQS)) in patients with multiple sclerosis (MS) and in normal controls. To correlate the VQS with the Kurtzke Expanded Disability Severity Score (EDSS) and sensory abnormalities in these patients.

We developed the VQS and tested its performance in patients with MS of various ages, MS types, and EDSS scores. We compared this with controls (normal volunteers or patients with other neurological diseases) who did not have sensory symptoms. In a subgroup, two examiners measured VQS independently at the same patient visit. Astandard C-128 tuning fork was used for the VQS measurement.

The VQS had a good inter-observer reproducibility (r=0.920, p<0.001). The VQS fell with increasing age in normals consistent with declining sensory function. The VQS was significantly lower in the multiple sclerosis patients compared with age - matched controls (p<0.001). Abnormalities in VQS were present in patients with brief duration of MS (<5 years) and low EDSS scores, correlating with the presence of sensory abnormalities early in the disease course in some patients. There was a strong correlation between the VQS and EDSS (r=-0.509). The VQS correlated with abnormal sensation in the hands (r=0.310), but did not meet statistical significance for abnormal sensation in the feet or face. Asecond cohort of MS patients was studied using a modified VQS measure (single stimulation, omitting forehead measurement). This reconfirmed the correlation between the modified VQS and EDSS as well as with age. The modified VQS may be useful in clinical practice since it takes little time and is strongly correlated with the EDSS (r=0.578).

The VQS provides a continuous sensory scale applicable in most patients with MS, which is measurable with standard bedside equipment, and which may avoid some of the pitfalls of sensory scoring in MS.

Quality of life instruments provide information that traditional outcome measures used in studies of multiple sclerosis do not. It is unclear if longer, disease-specific instruments provide more useful information than shorter, more general instruments, or whether patients prefer one type to another.

We conducted a cross-sectional study of quality of life in a multiple sclerosis clinic population using a mailed questionnaire that combined three different quality of life instruments; the SF-36, the Multiple Sclerosis Quality of Life Instrument-54, and the EuroQol EQ-5D. We assessed the feasability of using each instrument and patient preference for each, calculated correlation coefficients for the summary scores of each instrument and other measures of disease severity, and calculated odds ratios from proportional odds models comparing each instrument with the Expanded Disability Status Scale.

We did not find substantial differences between the three instruments. All were well-received by patients, and over 75% felt that the combination of the three instruments best assessed their quality of life. For each instrument there was substantial variability between patients with similar quality of life scores in terms of their disability (as assessed by the Expanded Disability Status Scale and their own perception of their disease severity and quality of life (on simple 1-10 scales).

Quality of life instruments are easy to use and well-received by patients, regardless of their length. There do not appear to be clinically important differences between general and disease-specific instruments. Each instrument appears to measure something other than a patient’s disability or perception of their own disease severity or quality of life.

Deep brain stimulation (DBS) is increasingly used to treat a variety of neurological conditions (e.g. movement disorders and chronic pain). This prospective study was designed to detect electrocardiogram (ECG) artifacts induced by deep brain stimulation and to investigate which factors (patient disease, electrode position within the brain or type of stimulation) produced these artifacts.

Twelve patients (four women, eight men) with deep brain stimulators were enrolled in the study. Patients were selected to represent the common indications for DBS (Parkinson's disease, tremor, dystonia), the common electrode locations (pallidum, thalamus, subthalamic nucleus) and the two types of stimulation (monopolar, bipolar). Patients had one ECG with the DBS turned 'on'and another with the DBS turned 'off'. The ECGs were then randomized and read by a cardiologist blinded to the status of the patient and DBS and artifacts were noted to be either present or absent.

The six patients using monopolar stimulation all had artifacts on their electrocardiograms. These artifacts were severe enough to interfere with ECG interpretation. There were no artifacts detected in the six patients using bipolar stimulation. Electrode location and patient disease appeared to have no effect on ECG artifact.

Deep brain stimulation can cause ECG artifacts when monopolar settings are used. These artifacts are not present with bipolar settings or when the DBS is turned 'off'. Knowledge of these potential ECG artifacts and how to avoid them is essential to facilitate accurate ECG interpretation.

Prediction of outcome after stroke is important for triage decisions, prognostic estimates for family and for appropriate resource utilization. Prognostication must be timely and simply applied. Several scales have shown good prognostic value. In Calgary, the Orpington Prognostic Score (OPS) has been used to predict outcome as an aid to rehabilitation triage. However, the OPS has not been assessed at one week for predictive capability.

Among patients admitted to a sub-acute stroke unit, OPS from the first week were examined to determine if any correlation existed between final disposition after rehabilitation and first week score. The predictive validity of the OPS at one week was compared to National Institute of Health Stroke Scale (NIHSS) score at 24 hours using logistic regression and receiver operator characteristics analysis. The primary outcome was final disposition after discharge from the stroke unit if the patient went directly home, or died, or from the inpatient rehabilitation unit.

The first week OPS was highly predictive of final disposition. However, no major advantage in using the first week OPS was observed when compared to 24h NIHSS score. Both scales were equally predictive of final disposition of stroke patients, post rehabilitation.

The first week OPS can be used to predict final outcome. The NIHSS at 24h provides the same prognostic information.

To prospectively compare somatosensory evoked potentials, electroencephalography (EEG) and transcranial Doppler ultrasound (TCD) for detection of cerebral ischemia during carotid endarterectomy (CEA).

Somatosensory evoked potentials and EEG recordings were attempted in 156 consecutive CEAs and TCD was also attempted in 91 of them. Recordings from all three modalities were obtained for at least 10 minutes before CEA, during CEAand for at least 15 minutes after CEA. Somatosensory evoked potentials peak-to-peak amplitude decrease of >50%, EEG amplitude decrease of >75%, and ipsilateral middle cerebral artery mean blood flow velocity (mean VMCAi) decrease >75% persisting for the entire period of internal carotid artery occlusion were individually considered to be diagnostic of cerebral ischemia. Clinical neurological examination was performed immediately prior to surgery and following recovery from general anaesthesia.

Somatosensory evoked potentials, EEG, and TCD were successfully obtained throughout the entire period of internal carotid artery occlusion in 99%, 95%, and 63% of patients respectively. Two patients (1.3%) suffered intraoperative cerebral infarction detected by clinical neurological examination and subsequent magnetic resonance imaging. Somatosensory evoked potentials accurately predicted intraoperative cerebral infarction in both instances without false negatives or false positives, EEG yielded one false negative result and no false positive results and VMCAi one true positive, four false positive and no false negative results. Transcranial Doppler ultrasound detection of emboli did not correlate with postoperative neurological deficits. Nevertheless the sensitivity and specificity of each test was not significantly different than the others because of the small number of disagreements between tests.

A >50% decrease in the cortically generated P25 amplitude of the median somatosensory evoked potentials, which persisted during the entire period of internal carotid artery occlusion, appears to be the most reliable method of monitoring for intraoperative ischemia in our hands because it accurately detected both intraoperative strokes with no false positive or false negative results.

Between August 25 and September 25, 2003 seven patients with West Nile virus neurological manifestations were identified through the hospital neurology consultation services in Calgary, Alberta, Canada. Three of the seven patients were treated with interferon alpha-2b (IFN alpha-2b). In this report we document the clinical characteristics of these seven cases.

Clinical and laboratory information was obtained from a retrospective review of patient hospital and clinic charts. Patients were included if they had serological evidence of West Nile virus infection and had clinical evidence of aseptic meningitis, encephalomyelitis, cerebellar syndrome or motor neuronopathy. Three patients received a treatment course of three million units IFN alpha-2b, administered by subcutaneous injection once per day for 14 days.

Four patients had cerebellar signs without change in consciousness, two had both encephalitis and neuromuscular weakness, and one patient had focal lower motor neuron arm weakness. The mean age was 52 (range 24 - 73). All patients had flu-like illness and fever as presenting symptoms and six had severe headaches. Two patients were immunocompromised prior to infection. Two patients with cerebellar signs (one with opsoclonus-myoclonus) improved spontaneously and exhibited only mild residual deficits on discharge. The other two patients with cerebellar findings developed brainstem involvement, one coinciding with and one subsequent to the cerebellar symptoms. Within one week of treatment with IFN alpha-2b these latter two patients showed marked improvement. One patient with encephalitis and neuromuscular weakness, was treated with IFN alpha-2b and subsequently recovered.

In this case review of seven patients, multiple neurological symptoms occurred in each patient and the neurological presentation was varied. Four patients had predominant cerebellar findings and one patient had opsoclonus-myoclonus, not previously reported. The marked improvement in three patients who received IFN alpha-2b raises preliminary optimism towards this potential treatment.

Chronic daily headache (CDH: headache on fifteen days a month or more) is one of the most common forms of chronic pain. The relative efficacy of different treatment methods for these patients needs to be determined.

To compare treatment outcomes for patients with CDH treated in a traditional office-based pharmacological treatment program with a second group treated in a multidisciplinary management program.

Patient outcomes were measured using changes in the Headache Disability Inventory (HDI) and the Short-Form-36 (SF-36) over the treatment period. Outcomes from seventy patients treated in an office setting were compared to thirty-seven patients treated in a multidisciplinary headache treatment program. Both groups received similar pharmacological treatment. All patients treated in the office setting and the majority of patients in the multidisciplinary program had transformed migraine.

Even though a reduction in headache days per month occurred, mean headache related disability (measured by HDI) and mean Health Related Quality of Life (HRQoL measured by SF-36) did not improve for the patient group treated in the office setting but did improve significantly for the patient group treated in the multidisciplinary headache program.

For patients with CDH, headache-related disability and HRQoL is more likely to improve with management in a multidisciplinary headache treatment program as compared to the traditional specialist consultation - family physician office-based setting.

Motor and sensory nerve conductions, F responses, sympathetic skin responses and R-R interval variations (RRIV) were studied to determine the type of peripheral neuropathy among patients with leprosy.

Twenty-nine consecutive patients with leprosy (25 male, 4 female) hospitalized in the “Istanbul Leprosy Hospital'' between January - December, 1999 were included in this study. Ten patients had borderline lepromatous leprosy, and 19 had lepromatous leprosy. None of the patients studied had the tuberculoid form. The mean age was 55±12 years. The control group consisted of 30 (26 male, 4 female) healthy volunteers (mean age: 58.1±7.8 years). All subjects included in the study underwent neurological examination and electrophysiological evaluation. Standard procedures were performed for evaluating sensory and motor conduction studies. Motor studies were carried out on both left and right median, ulnar, tibial and common peroneal nerves while median, ulnar, sural and superficial peroneal nerves were examined for sensory studies. Sympathetic skin response recordings on both hands and RRIV recordings on precordial region were done in order to evaluate the autonomic involvement.

The lower extremity was found to be more severely affected than the upper, and sensory impairment predominated over motor. Of 58 upper limbs examined, no sympathetic skin responses was recorded in 46 (79.3%). Compared with the controls, the RRIVs of the leprosy patients were found to be reduced during both resting and deep forced hyperventilation.

Our results indicate that leprosy causes a predominantly axonal polyneuropathy that is more severe in the lower extremities. Sensory nerve damage is accompanied by autonomic involvement.

Cerebral vasospasm adversely impacts the outcome of those suffering aneurysmal subarachnoid hemorrhage (SAH). Prediction of vasospasm could improve outcomes. We hypothesized that preclinical vasospasm would be heralded by an increase in cerebral oxygen extractions (AVDO2) which could be detected by jugular bulb oximetry. A pilot study was conducted to address this hypothesis.

Fourteen consenting patients with aneurysmal SAH, undergoing early surgery, were entered into the study. Four patients were withdrawn from the study secondary to failure of catheters or religious belief. At the time of craniotomy, a jugular bulb catheter was placed. Post-operatively, arterial and jugular bulb blood samples were taken every 12 hours to calculate AVDO2. As this was an observational study, no change in management occurred based on measurements.

Four of 10 patients had clinical vasospasm. These patients had a significant rise in AVDO2 approximately one day prior to the onset of neurologic deficits (P<0.001). Symptoms resolved along with a significant improvement in AVDO2 on instituting hypertensive, hemo-dilutional, and hypervolemic therapy in these patients. The six patients who did not exhibit clinical vasospasm did not demonstrate significant rise in AVDO2.

Jugular bulb oximetry is simple and cost effective. Increases in AVDO2 using this technique were predictive of clinically evident vasospasm in the subsequent hours to days. This investigation supports a larger study to assess the utility of jugular bulb oximetry in predicting vasospasm in aneurysmal SAH.

Current helmet testing standards do not address the rotational components of an impact to the head. We describe a new testing paradigm used to measure the rotational acceleration of a headform and a protective helmet following an impact to the head in the horizontal plane. This impact simulation allows for the testing of currently available head protection devices in conditions thought to be important for the generation of cerebral concussion. The degree to which a particular helmet dampens rotational acceleration, and thus protects against concussion, can be assessed.

Our testing device consists of a pneumatic piston that provides a measured impact to a standard headform. Four different helmets were tested using the described paradigm.

Acceleration curves for each helmet and the corresponding headform are presented.

Clear differences in rotational acceleration were demonstrated. Possible avenues of further investigation are discussed.

The growing science and technology of various neurosurgical areas fosters subspecialization. The transmission of this expanding knowledge base to the neurosurgical resident becomes an increasing challenge. A survey of neurosurgical residency program directors was undertaken to evaluate their response to the budding subspecialization of spine surgery within general neurosurgery.

A survey requesting background data, educational infrastructure and prevailing opinion was distributed to all 13 neurosurgical program directors in Canada. The responses were tabulated and results recorded. It is upon these results that conclusions and proposed directions are based.

The current practice of the overwhelming majority of Canadian academic neurosurgical centers is to have neurosurgical spinal subspecialists working under the umbrella of the general neurosurgical division. A large percentage of neurosurgical program directors in Canada believe that the management of spinal disease, including both intradural procedures and instrumentation, is and should remain an integral part of general neurosurgical training. A consensus statement regarding the requirements of neurosurgical training in spinal disorders is the expressed desire of almost all program directors. A proposed direction and resolution is discussed.

Medical error is an extremely important component of patient safety and requires intense study. The present investigation undertook to examine patients' perceptions and attitudes regarding medical error.

Qualitative case study methodology was used. We conducted 30 face-to-face interviews with patients within one week of undergoing a neurosurgical operation for a brain tumour. Interviews were audiotaped and transcribed and the data subjected to thematic analysis.

Three overarching themes emerged from the data: 1) trust in the patient's surgeon was of paramount importance; 2) patients'views toward medical error varied between fear and vulnerability to no concern; and 3) discussion of error was felt to be beneficial as it could help the medical profession decrease future errors and could help dispel the patient's fear and anxiety about the upcoming surgery.

Patients'trust in their physician/surgeon is of paramount importance in allaying their fears about the possible occurrence and impact of medical error during their treatment. The level of concern about error varies among patients, but most felt that discussion of error was a good thing.

Frontotemporal dementia is a neurodegenerative disease affecting mostly the frontal and/or temporal lobes, with neuronal loss and intraneuronal and/or intraglial inclusions composed of hyperphosphorylated microtubule-associated protein tau and ubiquitin. Missense and splice site mutations in the TAU gene have been identified in approximately 15% of all frontotemporal dementia cases. In this study, we evaluated the involvement of mutations in the TAU gene in development of frontotemporal dementia phenotype in patients of French or English Canadian origins.

Fourteen patients with frontotemporal dementia phenotype and 98 normal controls were recruited for the study. The TAU gene was screened by sequencing and denaturing high performance liquid chromatography.

No mutations, except some new polymorphisms, were detected in the TAU gene of these patients. One polymorphism, however, may play a role in pathogenesis.

Our results agree with previous work suggesting that mutations in this gene are not a frequent cause of the frontotemporal dementia phenotype in Canadian patients.

The role of neural transplantation as a restorative strategy for spinal cord injury continues to be intensely investigated. Ideally, the tissue source for transplantation must be readily available, free of disease and able to survive and mature following implantation into the adverse environment created by the injury. We have studied the use of a commercially available cell line of cultured human neurons (hNT neurons) as a tissue source for neural transplantation in spinal cord injury.

Following a left lateral thoracic hemisection, 54 immunosuppressed, female Wistar rats were randomly allocated into different treatment groups; hemisection only or hemisection and hNT cell transplantation (via a bridge, double or triple graft). Grafting occurred three days after spinal cord injury. After thirteen weeks the animals were sacrificed and tissue sections were stained with human neuron specific enolase and human specific neural cell adhesion molecule.

Immunohistochemical evidence of graft survival was displayed in 66.7% of the surviving, grafted animals. Fibre outgrowth, greatest in the bridge and triple grafts, was observed in both rostral and caudal directions essentially bridging the lesion. Double grafts were smaller, displaying less fibre outgrowth, which did not cross the lesion. Long fibre outgrowth was evident up to 2 cm from the graft as assessed by tracing and immunohistochemical studies.

Bridge and triple grafts displayed greater growth and enabled the hNT graft to essentially bridge the lesion. This suggests that hNT neurons have the potential to structurally reconnect the proximal and distal spinal cord across the region of injury.

Myoclonus is often associated with progressive myoclonic epilepsy or neurodegenerative conditions. Febrile myoclonus is a benign phenomenon, which has only been reported previously in one child.

The clinical features of three children with fever-induced myoclonus are described.

Fever-induced myoclonus is characterized by frequent myoclonus, which resolves with resolution of the fever in otherwise healthy children.

Recognition of fever-induced myoclonus as a benign phenomenon may prevent unnecessary investigations and interventions.

Le fait de reconnaître le myoclonus induit par l'hyperthermie comme un phÉnomène bÉnin peut Éviter des investigations et des interventions inutiles.

Infection related to external ventricular drain (EVD) use is a common neurosurgical complication. Modified catheters with a hydrophilic surface may impede bacterial adherence and thereby reduce catheter related cerebrospinal fluid (CSF) infection.

A prospective randomized clinical trial compared the occurrence of CSF infection related to use of either standard silastic or hydrogel coated EVD catheters (Bioglide®, Medtronic). Enrolment was available to all adult neurosurgery patients undergoing placement of a first EVD, at three university centers. The catheters were presoaked in a low concentration of bacitracin solution for 5-10 minutes prior to insertion. Bacterial infection was defined by heavy growth in a single CSF sample or light / medium growth in two consecutive samples. A secondary analysis was also conducted for “probable” CSF infection, including patients started on antibiotics after light / medium growth in a single CSF sample. Statistical analyses included Kaplan-Meier survival curve estimates accompanied by Log Rank and Breslow tests.

There were 158 randomized patients available to assess for EVD related infection of CSF. The two study groups had similar clinical characteristics including average duration of EVD use (8±4 days). Definite CSF infection occurred in seven and probable infection in another six (8% total). Infection incidence rose steadily from day 2 (1%) to day 11 (11%). There was no difference of daily occurrence of EVD infection between the two catheter types.

Infection remains a common hazard in the use of EVD, and we found no reduction of infection using the hydrogel-coated catheters when presoaked in low concentration bacitracin solution.

Head injury is an important cause of morbidity and mortality in pediatrics. Comprehensive studies on outcome are scarce despite significant clinical concern that multiple areas of functioning may be impaired following moderate to severe head injury. The literature suggests that sequelae include not only medical problems but also impairments in cognitive functioning.

Aretrospective medical and psychology chart review of patients, age 1-18 years, admitted to the Children's Hospital of Eastern Ontario with moderate (Glasgow Coma Scale [GCS] 9-12) or severe head injury (GCS ≤ 8) from November 1, 1993 until December 31, 1998 was conducted. Correlations were performed between medical variables (i.e., GCS, Pediatric Risk of Mortality [PRISM] III score, duration of ICU and hospital stay) and measures of intelligence and memory functioning.

Eighty-three children age 1 to 18 were included. Seventy percent of the children were classified as having a severe head injury. There was a mortality rate of thirteen percent. Younger age at injury, lower GCS, and higher PRISM III scores predicted higher mortality. Medical complications were documented systematically. Forty-four patients underwent at least one cognitive assessment and 17 of these children had intelligence testing at three points in time: baseline (< four months), early recovery (five to 15 months) and follow-up (16 to 38 months). The mean intelligence and memory scores fell within the average range at the latest point in follow-up. For those children who underwent three serial assessments, the mean verbal and performance IQ fell within the low average range at baseline improving significantly to fall within the average range by early recovery. Continued improvements were apparent in verbal memory beyond early recovery, with the mean obtained at follow-up falling within 1 SD of the normative mean. Despite the return to normal ranges for the group means the proportion of scores falling below 1.5 standard deviations from the mean was greater than population norms for verbal IQ, performance IQ and verbal memory. Lower GCS scores and longer duration of stay in ICU or hospital were predictive of lower nonverbal intelligence. Lower GCS was also predictive of lower visual memory scores.

This study describes a population of Canadian children who suffered moderate or severe traumatic brain injury. Initial GCS was the best predictor of mortality and cognitive outcome. These children demonstrated a temporal improvement in intelligence and memory functioning, with their mean performance on these cognitive measures falling within the average range at 16 to 38 months postinjury, although there was considerable variability in the outcomes between individuals.

Diffuse temporal lobe abnormalities can be observed on MRI of patients with mesial temporal lobe epilepsy (MTLE). Our objective was to perform qualitative and quantitative analyses of temporal lobe structures in patients with familial MTLE (FMTLE) and nonfamilial MTLE.

Two groups of patients were ascertained: 67 FMTLE patients (14 with refractory seizures) and 30 patients with nonfamilial refractory MTLE. We performed qualitative analyses of MRI (with multiplanar reconstruction) and volumes of hippocampi and anterior temporal lobes in all patients, and in a normal control group of 23 individuals. We used the Chi-square test and ANOVA for statistical analyses.

We identified anterior temporal lobe abnormalities by visual analysis in only 4% of FMTLE patients and atrophy of the anterior temporal lobe by volumetric analysis in 19%. In the group of nonfamilial MTLE patients we found anterior temporal lobe abnormalities by visual analysis in 17% of patients and anterior temporal lobe atrophy in 13%. Hippocampal atrophy was present in 90% of FMTLE and in 83% of nonfamilial MTLE. No signs of cortical dysplasia were observed.

Anterior temporal lobe atrophy and other abnormalities outside the mesial portion of temporal lobes were infrequent in both familial and nonfamilial MTLE patients. Despite the genetic basis, hippocampal atrophy in FMTLE is not associated with other abnormalities outside the mesial temporal regions.