Pharmacokinetics and tolerability of nasal versus intravenous midazolam in healthy Dutch volunteers: a single-dose, randomized-sequence, open-label, 2-period crossover pilot study.

BACKGROUND: Intranasal (IN) midazolam is a potential alternative to rectal diazepam for the acute treatment of epileptic seizures. OBJECTIVE: The purpose of this pilot study was to investigate the pharmacokinetics and tolerability of IN midazolam (50 mg/mL) compared with intravenous (IV) midazolam (2.5 mg) in healthy adult volunteers. METHODS: In this single-dose, randomized-sequence, open-label, 2-period crossover pilot study subjects were randomly assigned to receive IN or IV midazolam, with a washout period of at least 5 days between treatments. The 50-mg/mL IN midazolam formulation consisted of 5 mg midazolam base per 0.1 mL (1 spray) and was administered once in 1 nostril. The IV midazolam solution (2.5 mg) was infused over 10 seconds. Blood samples were taken before and at regular intervals up to 240 minutes after dosing. Pharmacokinetic data (ie, C(max), T(max), t(½), and AUC) were analyzed using a 2-compartment model. RESULTS: Of 9 volunteers screened and enrolled, 7 completed the study (mean age 34.1 [9.0] years; mean weight, 68.6 [10.4] kg, range 53-89 kg; 6 men, 3 women; all white). The mean C(max) of 78 (40) ng/mL was reached 44 minutes after IN administration, whereas the mean C(max) was 51 (5) ng/mL after IV administration. The mean estimated C(t=5 min) was 31.4 (28.1) ng/mL after IN administration. The elimination t(½) was 1.9 (0.41) hours for IN midazolam and 2.3 (0.19) hours for IV midazolam. The bioavailability of IN midazolam was 82%. There were few adverse events, with a local burning feeling in the nose being the most reported event (6 of 7 subjects). CONCLUSIONS: In this select group of healthy volunteers, concentrations of midazolam >30 ng/mL were reached within 5 minutes of IN administration at a dose of 5 mg/0.1 mL. A burning feeling in the nostril was the main adverse effect. Additional research is needed to evaluate the safety profile, convenience, satisfaction, and efficacy of nasal midazolam in the treatment of adults with seizures. This trial is registered at www.isrctn.org, No. ISRCTN79059168.

Memory processes and prefrontal network dysfunction in cryptogenic epilepsy.

PURPOSE: Impaired memory performance is the most frequently reported cognitive problem in patients with chronic epilepsy. To examine memory deficits many studies have focused on the role of the mesiotemporal lobe, mostly with hippocampal abnormalities. However, the role of the prefrontal brain remains unresolved. To investigate the neuronal correlates of working memory dysfunction in patients without structural lesions, a combined study of neurocognitive assessment, hippocampal and cerebral volumetry, and functional magnetic resonance imaging of temporal and frontal memory networks was performed. METHODS: Thirty-six patients with cryptogenic localization-related epilepsy and 21 healthy controls underwent neuropsychological assessment of intelligence (IQ) and memory. On T(1) -weighted images obtained by 3-Tesla magnetic resonance imaging (MRI), volumetry of the hippocampi and the cerebrum was performed. Functional MRI (fMRI) was performed with a novel picture encoding and Sternberg paradigm that activated different memory-mediating brain regions. Functional connectivity analysis comprised cross-correlation of signal time-series of the most strongly activated regions involved in working memory function. KEY FINDINGS: Patients with epilepsy displayed lower IQ values; impaired transient aspects of information processing, as indicated by lower scores on the digit-symbol substitution test (DSST); and decreased short-term memory performance relative to healthy controls, as measured with the Wechsler Adult Intelligence Scale subtests for working memory, and word and figure recognition. This could not be related to any hippocampal volume changes. No group differences were found regarding volumetry or fMRI-derived functional activation. In the Sternberg paradigm, a network involving the anterior cingulate and the middle and inferior frontal gyrus was activated. A reduced strength of four connections in this prefrontal network was associated with the DSST and word recognition performance in the patient group. SIGNIFICANCE: Deficits in the processes involved in transient working memory, and to a lesser extent in short-term memory, in patients with localization-related epilepsy of both temporal and extratemporal origin cannot be attributed to hippocampal atrophy or function only, but are also related to reduced functional connectivity in the prefrontal brain. Because patients with symptomatic lesions or mesiotemporal sclerosis were excluded from this study, the results cannot be explained by structural lesions. Therefore, the current findings highlight the influence of epilepsy on the prefrontal network integrity as a possible underlying problem of memory impairment.

Hippocampal MRI volumetry at 3 Tesla: reliability and practical guidance.

OBJECTIVES: Although volumetry of the hippocampus is considered to be an established technique, protocols reported in literature are not described in great detail. This article provides a complete and detailed protocol for hippocampal volumetry applicable to T1-weighted magnetic resonance (MR) images acquired at 3 Tesla, which has become the standard for structural brain research. MATERIALS AND METHODS: The protocol encompasses T1-weighted image acquisition at 3 Tesla, anatomic guidelines for manual hippocampus delineation, requirements of delineation software, reliability measures, and criteria to assess and ensure sufficient reliability. Moreover, the validity of the correction for total intracranial volume size was critically assessed. The protocol was applied by 2 readers to the MR images of 36 patients with cryptogenic localization-related epilepsy, 4 patients with unilateral hippocampal sclerosis, and 20 healthy control subjects. RESULTS: The uncorrected hippocampal volumes were 2923 +/- 500 mm3 (mean +/- SD) (left) and 3120 +/- 416 mm3 (right) for the patient group and 3185 +/- 411 mm3 (left) and 3302 +/- 411 mm3 (right) for the healthy control group. The volume of the 4 pathologic hippocampi of the patients with unilateral hippocampal sclerosis was 2980 +/- 422 mm3. The inter-reader reliability values were determined: intraclass-correlation-coefficient (ICC) = 0.87 (left) and 0.86 (right), percentage volume difference (VD) = 7.0 +/- 4.7% (left) and 6.0 +/- 3.8% (right), and overlap ratio (OR) = 0.82 +/- 0.04 (left) and 0.82 +/- 0.03 (right). The positive Pearson correlation between hippocampal volume and total intracranial volume was found to be low: r = 0.48 (P = 0.03, left) and r = 0.62 (P = 0.004, right) and did not significantly reduce the volumetric variances, showing the limited benefit of the brain size correction. CONCLUSIONS: A protocol was described to determine hippocampal volumes based on 3 Tesla MR images with high inter-reader reliability. Although the reliability of hippocampal volumetry at 3 Tesla was similar to the literature values obtained at 1.5 Tesla, hippocampal border definition is argued to be more confident and easier because of the improved signal-to-noise characteristics.

White matter lesions in patients with localization-related epilepsy.

OBJECTIVES: White matter lesions (WML) have been proven to be associated with cognitive impairment. As (1) the decline of cognitive function is the most frequent comorbid disorder in epilepsy, and (2) patients with epilepsy have a relatively high prevalence of WML, the question is raised whether WML in patients with epilepsy are also associated with cognitive decline. MATERIALS AND METHODS: A high-resolution magnetic resonance imaging examination was performed at 3.0 T, comprising T1-weighted, T2 relaxometry, and fluid-attenuated inversion recovery (FLAIR) sequences. Patients with localization-related epilepsy with impaired and unimpaired cognitive functioning and a healthy control group were included. Furthermore, the performance of an automated WML detection algorithm, based on regional intensity evaluation, was assessed. RESULTS: The prevalence of WML, detected on 3.0 T FLAIR images, is 63% in healthy volunteers and 46% in patients with localization-related, cryptogenic epilepsy. No relationship between WML volume and cognitive performance was observed. The WML volumes from the automated segmentation method were found to be significantly correlated to the volumes obtained by neuroradiologic assessment. CONCLUSIONS: No relations could be found between WML and cognition in the well-defined population of patients with epilepsy. Other clinical characteristics of chronic epilepsy, such as seizures, age of onset, and medication are more likely to play an important role in cognitive decline. Furthermore, the automated WML detection algorithm using a regional Z-score analysis can successfully segment and quantify the WML on FLAIR images.

Cognitive fMRI and neuropsychological assessment in patients with secondarily generalized seizures.

OBJECTIVES: Cognitive dysfunction is a frequent comorbid disorder in epilepsy which has been associated with high seizure frequency. We examined the effect of secondarily generalized tonic-clonic seizures (SGTCS) on cognitive dysfunction using neuropsychological assessment and fMRI. PATIENTS AND METHODS: Sixteen patients with localization-related epilepsy of varying etiologies and SGTCS underwent extensive neuropsychological assessment. Functional MRI was performed probing the frontal and temporal lobes with two paradigms aimed at investigating speed of mental processing and working memory. RESULTS: A high number of total lifetime SGTCS was associated with lower intelligence scores. Moreover, a trend towards cognitive decline related to the number of SGTCS was observed. A relatively increased prefrontal activation related to the number of SGTCS was demonstrated, plus a trend towards a decreased activation in the frontotemporal areas. CONCLUSION: High numbers of SGTCS are associated with a drop in intelligence scores and altered prefrontal brain activation. A shift from frontotemporal to prefrontal activation seems to have occurred, suggesting that a functional reorganization of working memory is induced by a high number of SGTCS. It remains uncertain if this reorganization reflects a compensation mechanism, or the underlying pathological processes of cognitive dysfunction.

A cost-effectiveness decision model for antiepileptic drug treatment in newly diagnosed epilepsy patients.

OBJECTIVE: To establish cost-effectiveness of antiepileptic drug (AED) treatment strategies of newly diagnosed patients with epilepsy. METHODS: A decision analysis was carried out comparing effectiveness and treatment cost of six treatment strategies comprising carbamazepine (CBZ), lamotrigine (LTG), and valproate (VPA) as first-line and second-line drugs. Three outcome groups were defined: complete success, partial success, and failure. Data on seizure control and failure due to adverse effects were derived from the literature. Data on resource use and costs were collected for each outcome group by means of a patient survey. RESULTS: Cost data were obtained from 71 patients. Cost increased from complete success to failure outcome groups. The probability of obtaining complete success varied from 64% (VPA-CBZ strategy) to 74% (LTG-VPA strategy). The strategy LTG-VPA was more effective than the least expensive strategy CBZ-VPA, but at higher costs per additional effectively treated patient. Probabilistic sensitivity analysis confirmed these findings to be robust. Subsequent analysis showed that changing inclusion criteria used in the selection of the studies from the literature had a major effect on cost-effectiveness ratios of the various strategies. The probability that LTG first-line therapy is the most cost-effective option remains small, even defining a high cost-effectiveness threshold. Nevertheless, LTG second-line strategies can be cost-effective depending on the willingness to pay for patient improvement. CONCLUSIONS: Only a few studies satisfied our inclusion criteria for employment in our decision model. Our model supports the use of conventional AEDs as first-line options for patients with newly diagnosed epilepsy. LTG second-line therapy is likely to be the most cost-effective option in case society is willing to pay more than Euro 6000 for an additional successfully treated patient. This study also illustrates that, with the data presently available, the outcome of decision analysis for AED treatment choice depends on the inclusion criteria used to select trials. Prospective real-life studies are needed in which first- and second-line treatment strategies are compared with respect to both effectiveness and costs.

Functional MRI reveals declined prefrontal cortex activation in patients with epilepsy on topiramate therapy.

Functional magnetic resonance imaging of covert word generation was used to examine brain activation abnormalities associated with topiramate-induced cognitive language impairment in patients with epilepsy. Compared with a control epilepsy group, in the topiramate-treated group, there was significantly less activation in the language-mediating regions of the prefrontal cortex; the topiramate group also had significantly lower neuropsychological language scores. These findings suggest that topiramate has a critical effect on the cerebral neural systems that mediate expressive language.

The costs of epilepsy in three different populations of patients with epilepsy.

The purpose of this study was to estimate the costs of care in three different populations of patients with epilepsy (general practices (GP), University Hospital (UH), and Epilepsy Center (EC)), and to analyse the distribution of costs by type of services for each patient group. A cost diary was developed to obtain prospective information on epilepsy-attributable service use over a period of 3 months. Similar information over the previous 3 months was obtained from a cost questionnaire. In addition, a quality of life inventory (QOLIE-31) was used. Standard cost lists were applied for the valuation of the direct cost items. A sensitivity analysis was performed for certain cost items for which no reliable data were available. One hundred and sixteen patients with established epilepsy were included, and the mean costs per patient per month (in Euros) ranged from 52.08 to 357.63. Patients from GP appeared to have lower direct costs, spent less time in seeking or undergoing a treatment, and reported lower seizure frequencies and less severe seizure types than the patients from the other patient groups. Patients from the EC reported the highest productivity changes and unemployment rates and also had the lowest scores on the QOLIE-31. The cost items anti-epileptic drugs, hospital services, unpaid care, and transportation accounted for the majority of the total direct costs.

The diagnosis of epileptic and non-epileptic seizures.

The aim of this prospective population-based study was to systematically define a cluster of diagnostic items which can assist in the early identification and classification of epileptic and non-epileptic seizures. A cohort of patients aged > or =14 years, suspected with a first epileptic seizure, were included in this study. A team of neurologists evaluated and classified all cases. Diagnostic items for epileptic and non-epileptic seizures were identified using logistic regression analysis. Three hundred and fifty cases entered this study. Distinctive features for epileptic seizures were postictal confusion (OR 0.09), an epileptiform EEG pattern (OR 0.02), and abnormal neuroimaging findings (OR 0.07), whereas for non-epileptic seizures of organic origin there was a history of hypertension (OR 7.5), and provoking factors (OR 13.4) such as exercise and warmth. Diagnostic items for seizures of non-organic origin were a history of febrile seizures (OR 5.8), treatment by a psychologist or psychiatrist (OR 9.1), and presentiment of the seizure (OR 3.7) such as a feeling of choking and palpitations. A separate analysis for the patients who were systematically investigated provided some additional diagnostic items for the different subgroups of patients. For instance, back arching during the seizure for the patients with seizures of non-organic origin and female sex for the patients with non-epileptic seizures of organic origin.

Systematic review and meta-analysis of incidence studies of epilepsy and unprovoked seizures.

PURPOSE: To evaluate the methodology of incidence studies of epilepsy and unprovoked seizures and to assess the value of their findings by summarizing their results. METHODS: A Medline literature search from January 1966 to December 1999 was conducted. In each selected study, key methodologic items such as case definition and study design were evaluated. Furthermore, a quantitative meta-analysis of the incidence data was performed. RESULTS: Forty incidence studies met the inclusion criteria. There was considerable heterogeneity in study methodology, and the methodologic quality score was generally low. The median incidence rate of epilepsy and unprovoked seizures was 47.4 and 56 per 100,000, respectively. The age-specific incidence of epilepsy was high in those aged 60 years or older, but was highest in childhood. Males had a slightly higher incidence of epilepsy (median, 50.7/100,000) than did females (median, 46.2/100,000), and partial seizures seemed to occur more often than generalized seizures. Developing countries had a higher incidence rate of epilepsy (median, 68.7/100,000) than did industrialized countries (median, 43.4/100,000). Similar results were found for unprovoked seizures. The incidence of epilepsy over time appears to decrease in children, whereas it increases in the elderly. CONCLUSIONS: The age-specific incidence of epilepsy showed a bimodal distribution with the highest peak in childhood. No definitive conclusions could be reached for the incidence of unprovoked seizures and other specific incidence rates of epilepsy. More incidence studies with an adequate study methodology are needed to explore geographic variations and time trends of the incidence of epilepsy and unprovoked seizures.

Splinting vs surgery in the treatment of carpal tunnel syndrome: a randomized controlled trial.

CONTEXT: Carpal tunnel syndrome (CTS) can be treated with nonsurgical or surgical options. However, there is no consensus on the most effective method of treatment. OBJECTIVE: To compare the short-term and long-term efficacy of splinting and surgery for relieving the symptoms of CTS. DESIGN, SETTING, AND PATIENTS: A randomized controlled trial conducted from October 1998 to April 2000 at 13 neurological outpatient clinics in the Netherlands. A total of 176 patients with clinically and electrophysiologically confirmed idiopathic CTS were assigned to wrist splinting during the night for at least 6 weeks (89 patients) or open carpal tunnel release (87 patients); 147 patients (84%) completed the final follow-up assessment 18 months after randomization. MAIN OUTCOME MEASURES: General improvement, number of nights waking up due to symptoms, and severity of symptoms. RESULTS: In the intention-to-treat analyses, surgery was more effective than splinting on all outcome measures. The success rates (based on general improvement) after 3 months were 80% for the surgery group (62/78 patients) vs 54% for the splinting group (46/86 patients), which is a difference of 26% (95% confidence interval [CI], 12%-40%; P<.001). After 18 months, the success rates increased to 90% for the surgery group (61/68 patients) vs 75% for the splinting group (59/79 patients), which is a difference of 15% (95% CI, 3%-27%; P =.02). However, by that time 41% of patients (32/79) in the splint group had also received the surgery treatment. CONCLUSION: Treatment with open carpal tunnel release surgery resulted in better outcomes than treatment with wrist splinting for patients with CTS.

Conservative treatment options for carpal tunnel syndrome: a systematic review of randomised controlled trials.

Carpal tunnel syndrome (CTS) is a common disorder, for which various conservative treatment options are available. The objective of this study is to determine the efficacy of the various conservative treatment options for relieving the symptoms of CTS. Computer-aided searches of MEDLINE (1/1966 to 3/2000), EMBASE (1/1988 to 2/2000) and the Cochrane Controlled Trials Register (2000, issue 1) were conducted, together with reference checking. Included were randomised controlled trials evaluating the efficacy of conservative treatment options in a study population of CTS patients, with a full report published in English, German, French or Dutch. Two reviewers independently selected the studies. Fourteen randomised controlled trials were included in the review. Assessment of methodological quality and data-extraction was independently performed by two reviewers. A rating system, based on the number of studies and their methodological quality and findings, was used to determine the strength of the available evidence for the efficacy of the treatment. Diuretics, pyridoxine, non-steroidal anti-inflammatory drugs, yoga and laser-acupuncture seem to be ineffective in providing short-term symptom relief (varying levels of evidence) and steroid injections seem to be effective (limited evidence). There is conflicting evidence for the efficacy of ultrasound and oral steroids. For providing long-term relief from symptoms there is limited evidence that ultrasound is effective, and that splinting is less effective than surgery. In conclusion, there is still little known about the efficacy of most conservative treatment options for CTS. To establish stronger evidence more high quality trials are needed.