Intracranial dural arteriovenous fistula with pial venous drainage may present with hemorrhage or focal neurologic deficit and may be difficult to treat. We wish to summarize the therapeutic approaches to these potentially dangerous lesions and to demonstrate how endovascular and neurosurgical therapies may have complimentary roles in their management.

The clinical and radiological records of all patients who presented to our institution with intracranial dural arteriovenous fistula over the last 5 years were reviewed. In those cases demonstrating pial venous drainage, details of presentation, imaging features, endovascular and surgical therapy and outcome were analyzed.

We identified 13 patients with these lesions, 7 of whom presented with intracranial hemorrhage. Six patients were treated with embolization alone. Angiographic cure was achieved in 4. There was one complication in this group, a subarachnoid hemorrhage following glue injection. Four patients were treated with embolization followed by surgical occlusion of the pial venous drainage. Angiographic cure was achieved in all 4. There was one complication in this group, a facial nerve palsy following glue injection. Three patients were treated by surgery alone, with no complications and complete cure in all.

Endovascular therapy of intracranial dural arteriovenous fistula may be curative but is often complex and carries definite risks. Neurosurgical ligation of pial draining veins, with pre-operative embolization when safe, may be a relatively more controlled method to achieve complete cure.

To determine the epidemiological profile for pediatric pseudotumor cerebri.

A retrospective case series was identified from a geographically limited region of 205,765 children aged 2-15 years at the only tertiary care pediatric hospital with all pediatric neurologists and ophthalmologists. Health records identified 35 children with ICD9 code 348.2 (benign intracranial hypertension) presenting between April 1, 1979 and March 31, 1994. After chart review, 29 cases were identified which satisfied modified Dandy's diagnostic criteria for pseudotumor cerebri.

The 29 cases ranged in age from 3-15 years. The annual incidence of symptomatic disease was 0.9 per 100,000 children (95% Cl 0.6, 1.4). Cases were 2.7 times more likely to be female (21/29, X² p = .01) and twice as likely to be adolescent (age 12-15 years), (X² p = .04). Based upon these distinctions, the following estimates of age and sex specific disease incidence were derived (based upon 100,000 child years of exposure): male age 2-11 years: 0.4; male age 12-15 years: 0.8; female age 2-11 years: 1.1; female age 12-16 years: 2.2.

These data appear to be unique for its the estimation of age and sex specific incidence rates for pediatric pseudotumor cerebri.

Currently, decreases in seizure frequency are the accepted efficacy outcome measure of therapeutic interventions in the management of patients with epilepsy. In a longitudinal randomized controlled trial of 10 subjects with intractable complex partial seizures who received left vagal nerve stimulation (VNS) to control seizures, it was found that the total number of consecutive seizure-free days is a significant efficacy outcome measure. Unlike measures in which percentage decreases in seizure frequency are calculated, measures of consecutive seizure days indicate improvement in the amount of time for which patients may function at a higher level in activities of daily living.

Fourteen day blocks of consecutive seizure-free days and 14 day blocks of consecutive days in which subjects had seizures were tabulated.

A Pearson correlation coefficient showed that prior to VNS subjects had few, if any, seizure free blocks of time and after VNS they had more blocks of time seizure free r = -1.00 and r = -0.99. The blocks of seizure-free days increased tenfold (x̄ 0.85 to x̄ 8.00) from 1991-1995 while mean seizure frequency in those blocks in which subjects had seizures only decreased from (x̄ 20.14 to x̄ 17.59) for the same time period. Correlations between total number of seizures after 24 months of VNS and after 50 months of VNS were r = 0.85 showing a consistency in the effect of VNS.

Monitoring the number of consecutive seizure-free days is a significant clinical outcome measure of VNS.

Early studies of cognitive motor control have shown deficits in complex reaction time tests of epileptic subjects. The purpose of this efficacy study was to determine whether chronic (28 months) stimulation of the left vagus nerve (VNS) to control seizures increased these deficits in 6 epileptic subjects with intractable complex partial seizures.

Subjects were assessed for simple reaction time, Test A, and subsequent Tests B and C which involved more complex cognitive strategies. Tests were done pre-operatively (S1) and at intervals, 6-8 weeks (S2-S3), and at 6 month intervals (S4-S6) over a 28 month period. Data were collected and collated on an Apple II E computer (Apple, Cupertino CA. U.S.A.) and on electronic switch pad. Data were analyzed using a repeated measures analysis of covariance technique with 2 within subject factors, day, and time of day.

2/11 cognitive measures showed a statistically significant difference. Error rate associated with Test A (simple reaction time) significantly decreased for the factor of day (repeated visits) p = .01. For Test C, error rates decreased in the afternoon (p = .03). This test involved the subjects ability to respond quickly to one signal while simultaneously ignoring a second signal. Data analysis of the covariate showed that the effects of VNS are weak in comparison to baseline differences and the frequency of nerve stimulation negatively predicts the number of wrong errors. High frequency stimulation results showed fewer errors than low frequency stimulation T = -2.31, p = .03.

Chronic stimulation of the left vagus nerve to control seizure activity does not impair cognitive motor control.

Stimulation of the left vagus nerve (VNS) has been shown to control seizures in double blinded crossover studies in man. Animal studies have reported vagal afferent induced depression of nociceptive and motor reflexes which may be caused by an effect on the descending reticular system controlling spinal cord function. Anticonvulsant drug therapy may cause postural instability. The effects of VNS are assessed not only from the perspective of seizure control but also from the view of potential harm to other bodily systems. Long term (2¼ years) effects of VNS were compared to postural stability analyses.

8 subjects, 2 were females, mean age 34.5 ± 8.23 SD years, with intractable complex partial seizures, taking 3 anticonvulsant drugs were assessed for postural stability in quiet standing and while moving forwards, backwards and sideways with eyes open (EO) and eyes closed (EC). Data were collected and collated using an AMTI Biomechanics immovable forceplate, Newton M.A. U.S.A. The study design was longitudinal with pre-operative baseline data collected prior to neurostimulation and at intervals post operatively.

4/8 balance measures showed significant changes from pre-operative values and after 2¼ years of stimulation. Area of sway (EO) in quiet standing p = .022 and total sway (EC) in the moving state p = .019 and total sway (EC) in quiet standing showed an increase in sway p = .003. Area of sway (EC) p = .004 tended to decrease. Regression analysis for frequency of stimulation showed an increase in sway with higher frequencies T = 1.99, P = .05.

Chronic VNS does not augment postural instability.

In many countries, neurosurgical care is concentrated in regional centres, which often necessitates the inter-hospital transfer of patients with head injury for optimal treatment. The aim of this study was to evaluate the role of teleradiology in the management of head-injured patients when referred from a district general hospital to a tertiary neurosurgical centre.

Prospective data were collected over a fifteen month period from March '95 to May '96. Head-injured patients referred without the facility of teleradiology (Group 1), were compared to similar patients referred with teleradiologie images (Group 2), with particular regard to therapeutic intervention before transfer and adverse events during transfer.

There were 28 patients in Group 1 and 35 in Group 2, of which 31 were transferred. Both groups were comparable with respect to age, admission Glasgow Coma Scale score, and intracranial pathology. For patients transferred with teleradiology consultation (Group 2), therapeutic interventions were more (32.1% vs. 10.7%, p = 0.06), adverse events during transfer were significantly lower (6.4% vs. 32.1%, p = 0.01), and transfer time was reduced (72 vs. 80 minutes, p = 0.38). Four patients in Group 2 were treated by a mobile neurosurgical team at the referring hospital because of rapid clinical deterioration.

Our findings indicate that teleradiology has an important role in improving inter-hospital management of head-injured patients.

Weight gain has been recognized as a common adverse effect of valproic acid (VPA) that leads to discontinuation in some patients but its incidence and correlates have been rarely studied.

We have analyzed the records retrospectively and interviewed 70 adult patients attending an epilepsy clinic on VPA mono- or polytherapy followed over a median of 27 months (range 3-189), as well as 20 patients on carbamazepine (CBZ) monotherapy. Patients were divided into non-weight gainers (< 5% baseline body weight), mild-moderate weight gainers (5-10% body weight) and marked weight gainers (> 10% body weight). The following variables were statistically analyzed to determine their relationship to weight gain: gender, age, body mass index, drug dose, personal or family history of obesity and monotherapy versus polytherapy.

Seventy-one percent of the VPA group were weight gainers versus 43% in the CBZ group. A weight gain of more than 4 kg in 70% of the VPA group was observed. The weight gain was often sustained and frequently socially significant to the patients. Patients below or within normal range body mass index prior to the start of VPA experienced the most severe percentage weight gain. From the structured patient interviews, patients with no personal history of weight problems experienced the greatest initial weight increase.

Strategies should be devised to help patients avoid weight gain when starting on VPA, especially if they are not already overweight.

Skin rashes are a well known complication of antiepileptic drug (AED) treatment. It has also been recognized that some patients will develop rashes from multiple AEDs (cross sensitivity). There are very few studies that have attempted to determine the frequency of cross sensitivity among AEDs.

Charts of all patients attending an epilepsy outpatient clinic were reviewed to determine AED exposure and the occurrence of a rash from AEDs.

633 patients had 1,875 exposures to 14 AEDs. Rashes occurred from carbamazepine (N = 27), phenytoin ( N = 21), phenobarbital (N = 5) and lamotrigine (N = 1). A rash from 2 or more AEDs occurred in 14 patients and involved predominantly carbamazepine and phenytoin. Among the patients exposed to both phenytoin and carbamazepine 10/17 (58%) of patients with a rash from phenytoin also had a rash from carbamazepine; conversely 10/25 (40%) patients with a carbamazepine rash also had a rash from phenytoin. 4/5 patients with a phenobarbital rash were sensitive to carbamazepine and/or phenytoin. Amongst the other most commonly used AEDs no rashes occurred from valproic acid or clobazam.

The cross sensitivity rate for rashes involving carbamazepine and phenytoin is 40-58%. If a rash develops from either of these AEDs, valproate or clobazam are safe alternatives.

The most common cause of acromegaly is excess of growth hormone (GH) secretion.

We report a 42-year-old male patient, who had become acromegalic over the past 5 years. There were no visual changes or change in sexual function, no gynaecomastia or galactorrhoea. Both CT and MRI scans showed a large mass measuring 2.5 x 2.5 x 3.5 cm, originating from the sella turcica and extending into and totally filling up the sphenoid sinus with diffusely invasive features.

Basal serum GH level was within normal range, but insulin-like growth factor 1 (IGF-1) was elevated with slightly increased prolactin (PRL) and impaired GH secretory regulation as well. A pituitary adenoma was partially removed through transsphenoidal microsurgery. Pathology confirmed a mammo-somatotrophic adenoma but immunocytochemistry study of the tumour showed only positivity for PRL but not GH.

When acromegaly occurs without GH level elevation, one should pay attention that: 1) IGF-1 might be the cause of the clinical feature of acromegaly; 2) The tumour might undergo morphological transformation; and 3) Hyperinsulinemia or GH receptor antibody formation could also be the cause of the acromegalic appearance.