Stiripentol in the treatment of adults with focal epilepsy- a retrospective analysis

OBJECTIVES

The aim of the present study was to evaluate the safety and efficacy of the add-on treatment of stiripentol (STP) in adult patients with severely pharmacoresistant focal or multifocal epilepsy.

METHODS

Data on adult patients treated with STP from March 2007 to July 2020 and with at least one clinical follow-up (FU) were retrospectively reviewed. Data on tolerability, efficacy and concomitant medication were evaluated at baseline, 6 months (5.5 ± 1.6 months (mean ± SD)) and 12 months (13.1 ± 3.9 months (mean ± SD)).

RESULTS

Data of 22 patients (54.5% male, mean age 34.4 ± 17.79 years (mean ± SD), including mean duration of epilepsy 17.6 ± 25.5 years (mean ± SD), median seizure frequency 30 ± 20 (median ± MAD) per month, and 63.6% being severely intellectually disabled, with 3 to 18 previous anti-seizure-drugs (ASD), were collected. After 6 months, 72.7% of the patients were still taking STP, and 31% of the patients were responders, including 13% who were seizure-free. The 12-month retention rate was 54.4 %, the response rate was 36.4% and 13.6% of patients were seizure-free at the 12-month FU. Reasons for discontinuation were increased seizure frequency, hyperammonaemia and encephalopathy.

CONCLUSION

STP seems to be a useful option in the treatment of patients with severely pharmacoresistant epilepsy. Prospective trials are necessary to examine the efficacy of STP in adult patients with pharmacoresistant focal epilepsy.

[Epilepsy and Pregnancy]

BACKGROUND

On average, female patients with epilepsy have 0.9 children, which is below the birth rate of healthy women. One reason is insufficient counselling.

OBJECTIVES

To summarize the current data relevant to counselling pregnant women with epilepsy.

MATERIALS AND METHODS

Discussion of research and recommendations concerning seizure control during pregnancy, pregnancy and birth complications, congenital malformations, and breastfeeding.

RESULTS

Changes in seizure frequency during pregnancy are variable and partly due to changes in the serum concentrations of antiepileptic drugs. Epilepsy patients have a slightly higher risk for some pregnancy and birth complications including spontaneous abortion, pre- and postpartum bleeding, induction of labour, and caesarean section. In particular, the administration of valproic acid can lead to congenital malformations and a lower IQ of the child. Folic acid seems to have a protective effect. Data concerning breastfeeding are insufficient.

CONCLUSIONS

If possible, epilepsy patients should be treated with a low-dose monotherapy during pregnancy and valproic acid should be avoided. Treatment with lamotrigine requires frequent control of serum concentration. Supplementary folic acid (5 mg daily dose) is recommended. Epilepsy is not an indication for a caesarean section.

Stiripentol for the treatment of super-refractory status epilepticus

BACKGROUND

To determine whether stiripentol (STP) might be a treatment option in super-refractory status epilepticus (SRSE).

METHODS

Medical records of patients treated due to a status epilepticus in Marburg between January 2013 and June 2014 were reviewed for administration of STP. Primary outcome measures were resolution of SE after initiation of STP.

RESULTS

Five adult patients were started with STP due to SRSE. The median age was 78 years (interquartile range [IQR] 11 years), and four patients were female. The median duration of SRSE before initiation of STP was 39 days (IQR 16 days), and the median number of anticonvulsants used before was 6 (IQR 1). SRSE ceased in three patients within 2-4 days after the start of STP. In two patients, SRSE continued after administration of STP and further escalation of anticonvulsant regimen. Both were switched eventually to supportive care only. None serious side effects were observed while on STP.

CONCLUSIONS

Based on our presented cases and previous experimental animal data, STP may prove useful in treating super-refractory SE. Prospective trials are warranted to examine the efficacy of the STP in adults with refractory SE and to examine whether earlier treatment leads to better control of SE.

Brain energy metabolism in early MSA-P: A phosphorus and proton magnetic resonance spectroscopy study

INTRODUCTION

Recently, mutations in the COQ2 gene, encoding for an enzyme involved in coenzyme Q10 biosynthesis, have been suggested to confer susceptibility risk for multiple system atrophy (MSA). Thus, the possible role of mitochondrial dysfunction in the pathophysiology of MSA has emerged. Here, we studied brain energy metabolism in vivo in early MSA-parkinsonism (MSA-P) patients and compared to healthy controls.

METHODS

We have used combined phosphorus and proton magnetic resonance spectroscopy to measure high- and low-energy phosphates in the basal ganglia of early (Hoehn and Yahr stage I-III), probable MSA-P patients (N = 9) compared to healthy controls (N = 9).

RESULTS

No significant changes in the high energy phosphates and other parameters reflecting the energy status of the cells were found in the basal ganglia of MSA-P patients compared to healthy controls. N-acetylaspartate was significantly reduced in MSA-P compared to healthy controls and correlated with the Unified Multiple System Atrophy Rating Scale.

CONCLUSION

Brain energy metabolism in early MSA-P is not impaired, despite the presence of impaired neuronal integrity. This may imply that mitochondrial dysfunction may not play a primary role in the pathophysiology of MSA, at least in European populations.

Definition of DLPFC and M1 according to anatomical landmarks for navigated brain stimulation: inter-rater reliability, accuracy, and influence of gender and age

The optimization of the targeting of a defined cortical region is a challenge in the current practice of transcranial magnetic stimulation (TMS). The dorsolateral prefrontal cortex (DLPFC) and the primary motor cortex (M1) are among the most usual TMS targets, particularly in its "therapeutic" application. This study describes a practical algorithm to determine the anatomical location of the DLPFC and M1 using a three-dimensional (3D) brain reconstruction provided by a TMS-dedicated navigation system from individual magnetic resonance imaging (MRI) data. The coordinates of the right and left DLPFC and M1 were determined in 50 normal brains (100 hemispheres) by five different investigators using a standardized procedure. Inter-rater reliability was good, with 95% limits of agreement ranging between 7 and 16 mm for the different coordinates. As expressed in the Talairach space and compared with anatomical or imaging data from the literature, the coordinates of the DLPFC defined by our algorithm corresponded to the junction between BA9 and BA46, while M1 coordinates corresponded to the posterior border of hand representation. Finally, we found an influence of gender and possibly of age on some coordinates on both rostrocaudal and dorsoventral axes. Our algorithm only requires a short training and can be used to provide a reliable targeting of DLPFC and M1 between various TMS investigators. This method, based on an image-guided navigation system using individual MRI data, should be helpful to a variety of TMS studies, especially to standardize the procedure of stimulation in multicenter "therapeutic" studies.

Intraoperative ultrasound in malformations of cortical development

PURPOSE

Malformations of cortical development (MCD) are a common cause of medically refractory focal epilepsy. However, the intraoperative definition of MCD can be challenging. In this study we assess the feasibility of intraoperative ultrasound (IOUS) for the intraoperative localization of MCD.

MATERIALS AND METHODS

Five epilepsy patients with at least one suspected lesion of MCD were operated with the aid of IOUS. IOUS was compared to preoperative MRI and histopathology.

RESULTS

In three cases of focal cortical dysplasia (FCD) type IIB and one case of periventricular heterotopia, the lesions could be delineated well on IOUS and the configuration of the lesion corresponded to the appearance on MRI. However, only one of two FCD type I lesions could be detected on IOUS.

CONCLUSION

IOUS can be helpful in defining FCD IIB as well as periventricular heterotopia intraoperatively, but this seems to be more difficult in FCD type I.

[Primary brain tumors and brain metastases. Symptomatic epilepsy and driving ability - systematic review and expert opinion]

PURPOSE

Primary brain tumors and metastases are common causes of symptomatic epilepsy. Seizures, neurological and neuropsychological deficits can interfere with driving ability. The present paper aims to systematically review the incidence of epileptic seizures in brain tumor patients and to discuss driving ability in the context of the current German guidelines and expert opinions.

METHODS

To evaluate the incidence of epileptic seizures which occur at the beginning and in the course of the disease, we performed a systematic literature research in PubMed from 1960 to 2007. Additionally on the basis of this data we performed a survey collecting expert opinions regarding the driving ability of brain tumor patients from members of the German working groups "Arbeitsgemeinschaft für prächirurgische Epilepsiediagnostik und operative Epilepsietherapie" (Working Group for Presurgical Epilepsy Diagnostics and Operative Epileptic Therapy) and "Neuroonkologische Arbeitsgemeinschaft" (Neuro-oncological Working Group).

RESULTS

The incidence of epileptic seizures depends on the entity, dignity and localization of the tumor. The driving ability of brain tumor patients is not explicitly regulated in Germany. Of the interviewed experts 72% judged the guidelines to be precise enough and 44% did not want to deprive the patients of their driving ability without a first seizure, independent of the individual risk.

DISCUSSION

The available studies are methodologically insufficient and show that a further evaluation is necessary to assess the driving ability. Possible restrictions of the driving ability in patients with a high risk of seizures in the course of the disease have to take into account the balance between individual rights and the interests of the general public.

Magnetic resonance imaging in progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a tauopathy, presenting clinically most often with a symmetrical akinetic-rigid syndrome, postural instability, supranuclear gaze palsy and frontal dementia. In the absence of reliably validated biomarkers, the diagnosis of PSP in vivo is presently based on clinical criteria, which to date do not include supporting imaging findings, as is accepted for other neurodegenerative diseases. However, data from conventional magnetic resonance imaging (MRI) and various advanced MRI techniques including magnetic resonance volumetry, voxel-based morphometry, diffusion-weighted and diffusion-tensor imaging, magnetization transfer imaging and proton resonance spectroscopy suggest that MRI can contribute valuable information for the differential diagnosis of PSP. We review here the presently published literature concerning MRI in PSP and discuss the potential role of MRI in differentiating PSP from other parkinsonian syndromes.

Men and women are different: diffusion tensor imaging reveals sexual dimorphism in the microstructure of the thalamus, corpus callosum and cingulum

INTRODUCTION

Numerous magnetic resonance imaging (MRI) studies have addressed the question of morphological differences of the brain of men and women, reporting conflicting results regarding brain size and the ratio of gray and white matter. In the present study, we used diffusion tensor imaging (DTI) to delineate sex differences of brain white matter.

METHODS

We investigated brain microstructure in 25 male and 25 female healthy subjects using a 3T MRI scanner. Whole-head DTI scans were analyzed without a-priori hypothesis using Tract-Based Spatial Statistics (TBSS) calculating maps of fractional anisotropy (FA), radial diffusivity (RD, a potential marker of glial alteration and changes in myelination) and axial diffusivity (AD, a potential marker of axonal changes).

RESULTS

DTI revealed regional microstructural differences between the brains of male and female subjects. Those were prominent in the thalamus, corpus callosum and cingulum. Men showed significantly (p<0.0001) higher values of fractional anisotropy and lower radial diffusivity in these areas, suggesting that the observed differences are mainly due to differences in myelination.

DISCUSSION

As a novel finding we showed widespread differences in thalamic microstructure that have not been described previously. Additionally, the present study confirmed earlier DTI studies focusing on sexual dimorphism in the corpus callosum and cingulum. All changes appear to be based on differences in myelination. The sex differences in thalamic microstructure call for further studies on the underlying cause and the behavioral correlates of this sexual dimorphism. Future DTI group studies may carefully control for gender to avoid confounding.

The Wada test in Austrian, Dutch, German, and Swiss epilepsy centers from 2000 to 2005: a review of 1421 procedures

Twenty-six Austrian, Dutch, German, and Swiss epilepsy centers were asked to report on use of the Wada test (intracarotid amobarbital procedure, IAP) from 2000 to 2005 and to give their opinion regarding its role in the presurgical diagnosis of epilepsy. Sixteen of the 23 centers providing information had performed 1421 Wada tests, predominantly the classic bilateral procedure (73%). A slight nonsignificant decrease over time in Wada test frequency, despite slightly increasing numbers of resective procedures, could be observed. Complication rates were relatively low (1.09%; 0.36% with permanent deficit). Test protocols were similar even though no universal standard protocol exists. Clinicians rated the Wada test as having good reliability and validity for language determination, whereas they questioned its reliability and validity for memory lateralization. Several noninvasive functional imaging techniques are already in use. However, clinicians currently do not want to rely solely on noninvasive functional imaging in all patients.

Topiramate, nutrition and weight change: a prospective study

PURPOSE

To evaluate prospectively the relationship between appetite, food composition, nutritional habits and weight loss following administration of topiramate (TPM) and to identify predictors for TPM induced weight loss.

METHODS

22 patients with epilepsy who were started on TPM were prospectively followed for 6 months and contacted again after a mean follow-up time of 37.1 months.

RESULTS

Body mass index (BMI) loss occurred in 59% of patients, with a mean weight loss of 9.5 kg after 6 months while receiving TPM without further weight loss at the long term follow-up. Weight loss was associated with reduction in appetite without affecting food composition. Predictors for BMI loss after 6 months were high initial BMI and body fat. After 3 weeks of treatment with TPM, the recorded parameters did not predict BMI loss but at 3 months, weight loss, reduction of appetite and amount of food intake were predictive for the amount of BMI loss after 6 months.

Intravenous levetiracetam in the treatment of benzodiazepine refractory status epilepticus

In 2006, levetiracetam was approved as the first of the newer anticonvulsive drugs as an intravenous formulation (ivLEV) for patients with epileptic seizures who are unable to take oral medication. We report our experience with the use of ivLEV for the treatment of 18 episodes of benzodiazepine refractory focal status epilepticus (SE) in 16 patients, including four patients with secondary generalised SE. SE was controlled in all patients by the given combination of drugs; application of further antiepileptic medications after ivLEV was necessary in two episodes. No severe side effects occurred. Our data suggest that ivLEV may be an alternative for the treatment of SE in the future, even in patients that did not respond to benzodiazepines. A large prospective, randomised, controlled study is warranted to investigate the efficacy and safety of ivLEV for the treatment of SE.