Seizure-induced miosis

Seizure semiology: ILAE glossary of terms and their significance

This educational topical review and Task Force report aims to address learning objectives of the International League Against Epilepsy (ILAE) curriculum. We sought to extract detailed features involving semiology from video recordings and interpret semiological signs and symptoms that reflect the likely localization for focal seizures in patients with epilepsy. This glossary was developed by a working group of the ILAE Commission on Diagnostic Methods incorporating the EEG Task Force. This paper identifies commonly used terms to describe seizure semiology, provides definitions, signs and symptoms, and summarizes their clinical value in localizing and lateralizing focal seizures based on consensus in the published literature. Video-EEG examples are included to illustrate important features of semiology in patients with epilepsy.

Automated Pupillometry for Assessment of Treatment Success in Nonconvulsive Status Epilepticus

BACKGROUND

Altered pupillary function may reflect nonconvulsive status epilepticus (NCSE). Neurological pupil index (NPi) assessed by automated pupillometry is a surrogate marker of global pupillary function. We aimed to assess NPi changes in relation to NCSE treatment response.

METHODS

In this prospective observational study, serial automated pupillometry was performed in 68 NCSE episodes. In accordance with local standards, patients were treated with clonazepam (1-2 mg), levetiracetam (40 mg/kg), and lacosamide (5 mg/kg) in a stepwise approach under continuous electroencephalography monitoring until NCSE was terminated. Patients with refractory NCSE received individualized regimens. NPi was assessed bilaterally before and after each treatment step. For statistical analysis, the lower NPi of both sides (minNPi) was used. Nonparametric testing for matched samples and Cohen's d to estimate effect size were performed. Principal component analysis was applied to assess the contribution of baseline minNPi, age, sex, and NCSE duration to treatment outcome.

RESULTS

In 97.1% of 68 episodes, NCSE could be terminated; in 16.2%, NCSE was refractory. In 85.3% of episodes, an abnormal baseline minNPi ≤ 4.0 was obtained. After NCSE termination, minNPi increased significantly (p < 0.001). Cohen's d showed a strong effect size of 1.24 (95% confidence interval 0.88-1.61). Baseline minNPi was higher in clonazepam nonresponders vs. responders (p = 0.008), minNPi increased in responders (p < 0.001) but not in nonresponders. NCSE refractivity was associated with normal baseline minNPi (principal component analysis, component 1, 32.6% of variance, r = 0.78), male sex, and longer NCSE duration (component 2, 27.1% of variance, r = 0.62 and r = 0.78, respectively).

CONCLUSIONS

Automated pupillometry may be a helpful noninvasive neuromonitoring tool for the assessment of patients with NCSE and response to treatment.

Quantitative Infrared Pupillometry in Nonconvulsive Status Epilepticus

BACKGROUND

Nonconvulsive status epilepticus (NCSE) is a frequent disorder in neurocritical care and diagnosing it can be challenging. NCSE patients often show altered pupil function, but nature and extent may vary. Infrared pupillometry allows detection of subtle changes of pupil function. The neurological pupil index (NPi) is considered a surrogate marker of global pupil function which is supposed to be independent of absolute parameters such as the pupil diameter.

OBJECTIVE

Cross-sectional observational study to assess whether NPi is altered in NCSE.

METHODS

128 consecutive adult emergency patients who had experienced a suspected seizure, have not reached their prior functional level regarding level of consciousness, mental status or focal deficits, had no obvious clinical signs of status epilepticus and had an EEG indication as determined by the treating clinician for exclusion of NCSE were examined by routine EEG and pupillometry. Exclusion criteria were ocular comorbidity (n = 21) and poor EEG quality (n = 4). Pupillometry was performed once directly before the beginning of EEG recording. NCSE diagnosis (no NCSE, possible NCSE and confirmed NCSE) was established according to Salzburg consensus criteria blinded to pupillometry results. Group comparison was performed for right NPi, left NPi, lowest NPi of both sides (minNPi) and the absolute difference of both sides (diffNPi) applying non-parametric testing. In post-hoc analysis, receiver operating characteristics (ROC) of NCSE diagnosis (combined confirmed NCSE and possible NCSE) were performed for minNPi and diffNPi.

RESULTS

From 103 patients included in the final analysis, 5 (4.9%) had confirmed NCSE, 7 (6.8%) had possible NCSE. Right NPi (p = 0.002), left NPi (p < 0.001) and minNPi (p < 0.001) were significantly lower in "confirmed NCSE" and "possible NCSE" compared to "no NCSE"; diffNPi was significantly higher in "confirmed NCSE" and "possible NCSE" compared to "no NCSE" (p < 0.001). There was no significant difference of minNPi and diffNPi between "confirmed NCSE" and "possible NCSE". ROC analysis showed an optimal cut-off of minNPi for NCSE diagnosis of 4.0 (AUC = 0.93, 95% CI 0.86-0.99). Optimal ROC analysis cut-off of diffNPi for NCSE diagnosis was 0.2 (AUC = 0.89, 95% CI 0.80-0.99).

CONCLUSIONS

NPi was significantly reduced and the difference between left and right NPi was significantly higher in confirmed NCSE. An NPi < 4.0 on either side as well as an NPi difference of both sides > 0.2 may be potential indicators of NCSE. Infrared pupillometry may be a helpful diagnostic tool in the assessment of NCSE and should be studied further in larger populations.

Valproate-Induced Polycystic Ovary Syndrome in a Girl with Epilepsy: A Case Study

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common ovulatory disorder that can be induced by sodium valproate (VPA).

PATIENT

We report a case of PCOS that developed in a 15-year-old girl with idiopathic epilepsy after she took VPA. VPA administration stopped her seizures, but it also led to weight gain and amenorrhea, and the patient was diagnosed with PCOS on the basis of diagnostic imaging and serological examination results. Cessation of VPA administration led to reduced weight gain and restored menstruation.

CONCLUSIONS

The risk of PCOS developing in patients with epilepsy is known to be high, and the association of VPA with PCOS is well established, so if physicians feel this is the best drug to prescribe for female patients with epilepsy, they should carefully monitor the patients' weight and menstruation, and immediately perform ovarian imaging and hormonal examinations if any abnormalities are observed.

MANAGEMENT OF ENDOCRINE DISEASE: Secondary polycystic ovary syndrome: theoretical and practical aspects

PCOS is a clinical heterogeneous entity of female androgen excess diagnosed by exclusion of other disorders responsible for androgen excess. The concept of secondary PCOS implies that there is a primary well-defined cause leading to the PCOS phenotype with underlying androgen overproduction, regardless of the origin. In these cases, we presume the term of 'secondary PCOS' could be used. In all these conditions, the potential complete recovery of the hyperandrogenemic state as well as the remission of the PCOS phenotype should follow the removal of the cause. If accepted, these concepts could help clinicians to perform in-depth investigations of the potential factors or disorders responsible for the development of these specific forms of secondary PCOS. Additionally, this could contribute to develop further research on factors and mechanisms involved in the development of the classic and the nonclassic PCOS phenotypes.

Sexual dysfunction related to antiepileptic drugs in patients with epilepsy

INTRODUCTION

Epilepsy is a common disease that is mostly treated with antiepileptic drugs (AEDs). However, the sexual dysfunction (SD) side effects related to the use of AEDs have not received sufficient attention.

AREAS COVERED

The purpose of this review is to examine the current evidence on SD-related side effects of AEDs. The incidence, clinical features and major types of SD are summarized. Furthermore, various AEDs that may cause SDs are addressed in detail. Finally, we briefly summarize the treatments for SD related to AEDs.

EXPERT OPINION

SD related to AEDs is common. Symptoms include erectile dysfunction (ED), hyposexuality, hypersexuality and ejaculatory dysfunction. Traditional AEDs such as valproate and enzyme-inducing AEDs (EIAEDs) may produce high incidences of decreased libido. Recently, sexual function changes related to new AEDs have been reported. Topiramate, pregabalin and gabapentin may cause SD, whereas oxcarbazepine, lamotrigine and levetiracetam may improve sexual function. Although the treatment for SD related to AEDs remains unclear, switching to another AED may be an option. Further studies are necessary to better understand and treat SD related to AEDs.

The effects of constrained left versus right monocular viewing on the autonomic nervous system

Asymmetrical activation of right and left hemispheres differentially influences the autonomic nervous system. Additionally, each hemisphere primarily receives retinocollicular projections from the contralateral eye. To learn if asymmetrical hemispheric activation induced by monocular viewing would influence relative pupillary size and respiratory hippus variability (RHV), a measure of parasympathetic activity, healthy participants had their left, right or neither eye patched. Pupillary sizes were then recorded with infrared pupillography. Pupillary dilation was significantly greater with left than right eye viewing. RHV, however, was not different between eye viewing conditions. These differences in pupil dilatation may have been caused by relatively greater activation of the right hemispheric-mediated sympathetic activity induced by left monocular viewing or relatively greater deactivation of the left hemispheric-mediated parasympathetic activity induced by right eye patching. The absence of an asymmetry in RHV, however, suggests that hemispheric asymmetry of sympathetic activation was primarily responsible for this ocular asymmetry of pupil dilation.

Epilepsy and vitamin D

Several disorders, both systemic and those of the nervous system, have been linked with vitamin D deficiency. Neurological disorders with a vitamin D link include but are not limited to multiple sclerosis, Alzheimer and Parkinson disease, as well as cerebrovascular disorders. Epilepsy which is the second leading neurological disorder received much less attention. We review evidence supporting a link between vitamin D and epilepsy including those coming from ecological as well as interventional and animal studies. We also assess the literature on the interaction between antiepileptic drugs and vitamin D. Converging evidence indicates a role for vitamin D deficiency in the pathophysiology of epilepsy.

Neuro-ophthalmology Annual Review

PURPOSE

To provide a clinical update of the neuro-ophthalmology literature over the last twelve months.

DESIGN

This is an annual review of current literature from August 1, 2011 to August 1, 2012.

METHODS

The authors conducted a one year English language neuro-ophthalmology literature search using PubMed from August 1, 2011 to August 1, 2012 using the following search terms: pupil abnormalities, eye movements, diseases of muscle and musculoskeletal junction, optic nerve disorders, optic neuritis and multiple sclerosis, chiasm and posterior primary visual pathway lesions, increased intracranial pressure and related entities, tumors (e.g., meningioma) and aneurysm affecting the visual pathways, vascular diseases, higher visual functions, advances in neuroimaging, and miscellaneous topics in neuro-ophthalmology. The authors included original articles, review articles, and case reports, which revealed the new aspects and updates in neuro-ophthalmology. Letters to the editor, unpublished work, and abstracts were not included in this annual literature review. We propose to update the practicing clinical ophthalmologist on the most clinically relevant literature from the past year. However, this review is not meant to be all-inclusive and highlights only the literature most applicable to the practicing clinical ophthalmologist.

RESULTS

We reviewed the literature over the past year in neuro-ophthalmology of potential interest and relevance to the comprehensive ophthalmologist.

CONCLUSION

This annual review provides a brief update on a number of neuroophthalmic conditions that might be of interest to the practicing clinical ophthalmologist.

IPAD: the Integrated Pathway Analysis Database for Systematic Enrichment Analysis

Background

Next-Generation Sequencing (NGS) technologies and Genome-Wide Association Studies (GWAS) generate millions of reads and hundreds of datasets, and there is an urgent need for a better way to accurately interpret and distill such large amounts of data. Extensive pathway and network analysis allow for the discovery of highly significant pathways from a set of disease vs. healthy samples in the NGS and GWAS. Knowledge of activation of these processes will lead to elucidation of the complex biological pathways affected by drug treatment, to patient stratification studies of new and existing drug treatments, and to understanding the underlying anti-cancer drug effects. There are approximately 141 biological human pathway resources as of Jan 2012 according to the Pathguide database. However, most currently available resources do not contain disease, drug or organ specificity information such as disease-pathway, drug-pathway, and organ-pathway associations. Systematically integrating pathway, disease, drug and organ specificity together becomes increasingly crucial for understanding the interrelationships between signaling, metabolic and regulatory pathway, drug action, disease susceptibility, and organ specificity from high-throughput omics data (genomics, transcriptomics, proteomics and metabolomics).

Results

We designed the Integrated Pathway Analysis Database for Systematic Enrichment Analysis (IPAD, http://bioinfo.hsc.unt.edu/ipad), defining inter-association between pathway, disease, drug and organ specificity, based on six criteria: 1) comprehensive pathway coverage; 2) gene/protein to pathway/disease/drug/organ association; 3) inter-association between pathway, disease, drug, and organ; 4) multiple and quantitative measurement of enrichment and inter-association; 5) assessment of enrichment and inter-association analysis with the context of the existing biological knowledge and a "gold standard" constructed from reputable and reliable sources; and 6) cross-linking of multiple available data sources.

IPAD is a comprehensive database covering about 22,498 genes, 25,469 proteins, 1956 pathways, 6704 diseases, 5615 drugs, and 52 organs integrated from databases including the BioCarta, KEGG, NCI-Nature curated, Reactome, CTD, PharmGKB, DrugBank, PharmGKB, and HOMER. The database has a web-based user interface that allows users to perform enrichment analysis from genes/proteins/molecules and inter-association analysis from a pathway, disease, drug, and organ.

Moreover, the quality of the database was validated with the context of the existing biological knowledge and a "gold standard" constructed from reputable and reliable sources. Two case studies were also presented to demonstrate: 1) self-validation of enrichment analysis and inter-association analysis on brain-specific markers, and 2) identification of previously undiscovered components by the enrichment analysis from a prostate cancer study.

Conclusions

IPAD is a new resource for analyzing, identifying, and validating pathway, disease, drug, organ specificity and their inter-associations. The statistical method we developed for enrichment and similarity measurement and the two criteria we described for setting the threshold parameters can be extended to other enrichment applications. Enriched pathways, diseases, drugs, organs and their inter-associations can be searched, displayed, and downloaded from our online user interface. The current IPAD database can help users address a wide range of biological pathway related, disease susceptibility related, drug target related and organ specificity related questions in human disease studies.

Therapeutic potential for phenytoin: targeting Na(v)1.5 sodium channels to reduce migration and invasion in metastatic breast cancer

Voltage-gated Na(+) channels (VGSCs) are heteromeric membrane protein complexes containing pore-forming α subunits and smaller, non-pore-forming β subunits. VGSCs are classically expressed in excitable cells, including neurons and muscle cells, where they mediate action potential firing, neurite outgrowth, pathfinding, and migration. VGSCs are also expressed in metastatic cells from a number of cancers. The Na(v)1.5 α subunit (encoded by SCN5A) is expressed in breast cancer (BCa) cell lines, where it enhances migration and invasion. We studied the expression of SCN5A in BCa array data, and tested the effect of the VGSC-blocking anticonvulsant phenytoin (5,5-diphenylhydantoin) on Na(+) current, migration, and invasion in BCa cells. SCN5A was up-regulated in BCa samples in several datasets, and was more highly expressed in samples from patients who had a recurrence, metastasis, or died within 5 years. SCN5A was also overexpressed as an outlier in a subset of samples, and associated with increased odds of developing metastasis. Phenytoin inhibited transient and persistent Na(+) current recorded from strongly metastatic MDA-MB-231 cells, and this effect was more potent at depolarized holding voltages. It may thus be an effective VGSC-blocking drug in cancer cells, which typically have depolarized membrane potentials. At a concentration within the therapeutic range used to treat epilepsy, phenytoin significantly inhibited the migration and invasion of MDA-MB-231 cells, but had no effect on weakly metastatic MCF-7 cells, which do not express Na(+) currents. We conclude that phenytoin suppresses Na(+) current in VGSC-expressing metastatic BCa cells, thus inhibiting VGSC-dependent migration and invasion. Together, our data support the hypothesis that SCN5A is up-regulated in BCa, favoring an invasive/metastatic phenotype. We therefore propose that repurposing existing VGSC-blocking therapeutic drugs should be further investigated as a potential new strategy to improve patient outcomes in metastatic BCa.

Do lamotrigine and levetiracetam solve the problem of using sodium valproate in women with epilepsy?

Women with epilepsy, especially those of child-bearing age, are faced with difficult choices when it comes to choosing the most suitable antiepileptic drug (AED). This is particularly so for those with idiopathic generalized epilepsies, or those for whom seizure syndrome is not immediately apparent, where sodium valproate is still considered the drug of choice. While with treatment most might expect to become seizure free, without any adverse effects, other considerations for women mean that valproate is usually initially avoided, with other AEDs such as lamotrigine or levetiracetam being chosen in preference. Based on current information, this article attempts to provide an overview on whether or not the availability of these and other broad-spectrum AEDs have solved the difficulties of using valproate in women of child-bearing age.