Determine relative frequency of recurrent headache (HA) types in children and adolescents referred to a pediatric neurologist. Methods and subjects: Study design: Prospective, sequential, and observational. Setting: Private practice Pediatric Neurology Clinic in a Canadian city (Winnipeg). Patients and data collection: Information on those referred with HA between September 1998 and December 2001 was entered on data sheets. Patients were followed up for one month to four years.

Three hundred and twenty (69%) of 463 referred with HAhad recurrent HA. There were 172 males (54%) and 148 (46%) females. Their ages ranged from two years to 19 years (median: 11 years). They had had their HA disorder for one month to 14 years (median: two years) prior to assessment. Migraine was the main HA type in 124 (38%), tension-type headache (TTH) in 57 (18%) and mixed migraine and TTH in 101 (32%). Thus, 101 (45%) of 225 with migraine as one HAtype also had TTH.

Tension-type headache and migraine frequently co-exist and may represent a distinct headache type, at least in children; the association will likely influence response of affected children and adolescents to specific migraine treatments in clinical trials or practice.

Characterize chronic daily headache in those less than 20 years of age. Material and

Study design: Prospective, observational, and sequential.

Private practice Pediatric Neurology Clinic in a Canadian city (Winnipeg).

Data on those referred with headache between September 1998 and December 2001 were entered on data sheets. Patients were followed up for one month to four years.

One hundred and forty-three (31%) of 463 referred with headache had chronic daily headache with duration of one month to five years (median: eight months). The age range was 5.5 years to 20 years (median: 13 years). There were significantly more females (N=93) than males (N=50). The main groups were: (1) transformed migraine: 6 (4%), (2) transformed tension-type headache: 80 (56%) and (3) transformed comorbid migraine and tension-type headache: 39 (27%). Tension-type features dominated in 94%. Analgesia overuse occurred in two. Stressors were recognized in 60 (42%); anxiety disorder was diagnosed in 8 (6%), and depression in 13 (9%). Computed tomography scans were done in 31 (22%), and MRI/MR angiography in 8 (6%) and were normal or showed nonspecific incidental findings. Twenty-two (15%) were lost to follow-up; 115 of the remaining 121 (95%) were headache free or greatly improved, 63 (55%) without specific treatment.

Chronic daily headache is a common headache disorder in children and adolescents, especially in teenage girls. A prospective neuropsychiatric approach is necessary for evidenced-based management, since the condition has mental health, social and economic ramifications.

To examine self-reported prevalence data for migraine among adolescent Canadians and to explore how reported migraine treatment varies by age.

We analyzed the microdata files of the Canadian National Population Health Survey (1996-1997). Respondents reported whether they had “migraine headaches diagnosed by a health professional”. They also reported whether they received “any treatment or medication for migraine headaches”, with treatments subdivided into drug, diet or “other”.

99.9% of 173,216 eligible respondents reported whether they had migraine headaches. Migraine was reported by 2.4% of Canadian youth aged 12-14 years and by 5.0% of 15-19 year-olds compared to 7.2% of adults aged 20 years of age (p< 0.0001, chi-square). Active treatment was used by 51.0% - higher by females (53.1%) than males (44.7%) (p<0.0001 chi-square). Treatment was used by 45.1% of 12-14 year-olds, by 45.7% of 15-19 year-olds and by 51.5% of those 20 years (p=0.0027). The nature of the active treatment choice (drug, diet or other) did not significantly vary within the age groups studied.

We present robust estimates of self-report diagnosed migraine prevalence, derived from a large nationally representative population survey. Estimates of the prevalence of active treatment for migraine provide insight into the burden of migraine within this population.

Report on the clinical results following bilateral globus pallidus interna deep brain stimulation in four patients (one female and three males) with severe cervical dystonia, mean age 48 years (range 37-67).

All four patients had failed extensive medical and botulinum toxin treatment. The mean duration of the disease was nine years (range 4-15 years). Patients were assessed pre and postoperatively using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). Preoperatively, the mean TWSTRS total score was 43.2 (range 28-60.5). Posteroventral pallidal deep brain stimulators were inserted using MRI and microelectrode recording guidance. Last follow-up was 15 months for the four patients.

Mean reduction in the TWSTRS total scores at last follow- up was 73% (range 61- 85%). Improvement in pain occurred soon after deep brain stimulation surgery. Motor improvement was delayed and prolonged over several months. Frequent adjustment in the stimulation parameters was necessary in the first three months.

Bilateral pallidal stimulation is effective in management of selected cases of intractable cervical dystonia.

Determine the efficacy of thalamic deep brain stimulation (DBS) for tremor control among individuals with essential tremor (ET).

A clinical series of 52 consecutive individuals undergoing placement of a DBS system for treatment of ET completed an unblinded battery of subjective and objective measures at postoperative intervals of one, three, and 12 months, and annually thereafter up to three years. The assessment battery included measures of tremor and activities of daily living.

Both subjective and objective measures showed that stimulation was associated with significant improvement at nearly every postoperative interval as compared to pre-operative and stimulation 'off' ratings of activities of daily living functioning, midline tremor, contralateral upper extremity tremor, and contralateral lower extremity tremor. Ipsilateral tremor showed some improvement with stimulation, but only within the first three months. Trend analysis showed stable tremor control. Stimulation settings remained largely unchanged after the first three months. Dysarthria was more common among those with bilateral stimulation. A range of missing data estimation methods were performed, and subsequent analyses corroborated the main findings of the study.

Thalamic DBS is generally a well-tolerated and effective treatment for ET. Methodological and analytical recommendations are provided for the evaluation of long-term outcome.

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.

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.

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.

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.

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.

Body impact or collision is the risk factor underlying all sports-related concussions. This study sought to determine whether collision rates in elite hockey differ between games played on North American size rinks as compared to games played on larger international size ice surfaces.

Videotapes of games from the 2001 and 2002 National Hockey League Stanley Cup finals, World Junior championships and the 2002 Winter Olympics were analyzed, with all collisions counted and separated into various categories (player/player bodycheck, player/player into boards, player/boards, player/ice, head/stick, head/puck). Further subdivisions included collisions involving the head directly or indirectly. Twenty-two games were analyzed, 11 played on the small ice and 11 on the big ice.

Significantly more collisions of all types (in all categories and subdivisions within categories) were found to occur on the smaller North American ice surface (P value differences from 0.01 to 0.00001).

The results of this study showed significantly fewer collisions of all types in elite hockey games played on the international size ice surface. The comparison groups studied here did differ in some aspects other than ice size and so replication of the findings with even more closely matched groups will be needed before definitive conclusions can be drawn. However, if these findings are replicable, it would suggest that a change to uniform usage of the larger international rinks, with no rule changes or other alterations in the game, could provide direct primary prevention to reduce the number of collisions, and, by extension, concussions, that occur in the sport.

To study the role of diabetes, gynecomastia and CAG triplet repeat size as disease modifying factors of neurologic expression in spinal bulbar muscular atrophy (SBMA, Kennedy's disease).

Twenty unrelated SBMApatients with confirmatory genetic testing were reviewed. Patterns of neurologic involvement were assessed (e.g. bulbar, asymmetric, proximal, distal, motor and sensory). Slopes of disease progression were calculated from serial quantified neurologic examinations. Patterns of neurologic involvement and course were correlated to the presence of diabetes, gynecomastia and triplet repeat size.

Diabetes or glucose impairment occurred in nine and 11 had gynecomastia. Patterns of neurologic involvement and rates of progression did not correlate with these endocrine diseases or triplet repeat sizes. Correlation was seen between number of CAG repeats and age of onset weakness (r = -0.53, r2 = 29%, p = 0.01).

The specific neurotoxic effect of expanded CAGs appears limited to age of onset weakness in SBMA. Although significant, only 29% of the variability in onset age could be accounted for by polyglutamine size suggesting the importance of other unidentified factors. In this series diabetes or glucose impairment was more common than previously reported and, like gynecomastia, did not correlate with size of triplet repeats, severity or patterns of neurologic involvement. Modifying factors other than diabetes, gynecomastia or triplet repeat size are suggested in disease expression.

Friedrich ataxia (FRDA1) is most often the result of a homozygous GAA repeat expansion in the first intron of the frataxin gene (FRDA gene). This condition is seen in individuals of European, North African, Middle Eastern and Indian descent and has not been reported in Southeast Asian populations. Approximately 4% of FRDA1 patients are compound heterozygotes. These patients have a GAA expansion on one allele and a point mutation on the other and have been reported to have an atypical phenotype.

To describe a novel dinucleotide deletion in the FRDA gene in two Malaysian siblings with FRDA1.

Tertiary referral university hospital setting. Patients and

A previously healthy 10-year-old Malaysian boy, presented with fever, lethargy, headaches, dysarthria, dysphagia, vertigo and ataxia which developed over a one week period. His neurological exam revealed evidence of dysarthria and ataxia, mild generalized weakness and choreoform movements of the tongue and hands. His reflexes were absent and Babinski sign was present bilaterally. A nine-year-old sister was found to have mild ataxia but was otherwise neurologically intact.

Molecular genetic studies demonstrated that both siblings were compound heterozygotes with a GAA expansion on one allele and a novel dinucleotide deletion on the other allele.

We describe a novel dinucleotide deletion in the first exon of the FRDA gene in two siblings with FRDA1. Additionally this is the first report of FRDA1 occurring in a family of southeast Asian descent, it demonstrates intrafamilial phenotypic variability, and confirms that atypical phenotypes are associated with compound heterozygosity.

Stroke incidence has fallen since 1950. Recent trends suggest that stroke incidence may be stabilizing or increasing. We investigated time trends in stroke occurrence and in-hospital morbidity and mortality in the Calgary Health Region.

All patients admitted to hospitals in the Calgary Health Region between 1994 and 2002 with a primary discharge diagnosis code (ICD-9 or ICD-10) of stroke were included. In-hospital strokes were also included. Stroke type, date of admission, age, gender, discharge disposition (died, discharged) and in-hospital complications (pneumonia, pulmonary embolism, deep venous thrombosis) were recorded. Poisson and simple linear regression was used to model time trends of occurrence by stroke type and age-group and to extrapolate future time trends.

From 1994 to 2002, 11642 stroke events were observed. Of these, 9879 patients (84.8%) were discharged from hospital, 1763 (15.1%) died in hospital, and 591 (5.1%) developed in-hospital complications from pneumonia, pulmonary embolism or deep venous thrombosis. Both in-hospital mortality and complication rates were highest for hemorrhages. Over the period of study, the rate of stroke admission has remained stable. However, total numbers of stroke admission to hospital have faced a significant increase (p=0.012) due to the combination of increases in intracerebral hemorrhage (p=0.021) and ischemic stroke admissions (p=0.011). Sub-arachnoid hemorrhage rates have declined. In-hospital stroke mortality has experienced an overall decline due to a decrease in deaths from ischemic stroke, intracerebral hemorrhage and sub-arachnoid hemorrhage.

Although age-adjusted stroke occurrence rates were stable from 1994 to 2002, this is associated with both a sharp increase in the absolute number of stroke admissions and decline in proportional in-hospital mortality. Further research is needed into changes in stroke severity over time to understand the causes of declining in-hospital stroke mortality rates.

While the risk of developing seizures following a mild head injury has been reported and is thought to be low, the effect of mild head injury on patients with a pre-existing seizure disorder has not been reported. We present a series of cases where a strong temporal relationship between mild head injury and worsening of seizure frequency was observed.

Five cases were identified and reviewed in detail. Information was derived from clinic and hospital charts with attention to the degree of injury, pre- and postinjury seizure patterns and frequency.

One patient has primary generalized epilepsy and four have localization related epilepsy. Prior to the head injury, three of the patients were seizure free (range: two to 24 years). The patients suffered from mild head injuries with no or transient loss of consciousness and no focal neurological deficits. In all cases, the patients experienced a worsening of seizure control within days of the injury. In one case, the patient's seizure pattern returned to baseline one year after the accident, while in the remaining four cases, the patients continue to have medically refractory seizures.

A close temporal relationship between mild head injury and a worsening of seizure control was observed in five patients with epilepsy. Although further study is required, this observation suggests that a head injury that would be considered benign in the general population can have serious consequences such as recurrence of seizures and medical intractability in patients with epilepsy.