Characteristics and outcomes of patients with seizures according to the time of onset in relation to stroke

Repetitive Transcranial Magnetic Stimulation and Rehabilitation Therapy for Upper Limb Hemiparesis in Stroke Patients: A Narrative Review

Recent technological advances in non-invasive brain stimulation (NIBS) have led to the development of therapies for post-stroke upper extremity paralysis. Repetitive transcranial magnetic stimulation (rTMS), a NIBS technique, controls regional activity by non-invasively stimulating selected areas of the cerebral cortex. The therapeutic principle by which rTMS is thought to work is the correction of interhemispheric inhibition imbalances. The guidelines for rTMS for post-stroke upper limb paralysis have graded it as a highly effective treatment, and, based on functional brain imaging and neurophysiological testing, it has been shown to result in progress toward normalization. Our research group has published many reports showing improvement in upper limb function after administration of the NovEl Intervention Using Repetitive TMS and intensive one-to-one therapy (NEURO), demonstrating its safety and efficacy. Based on the findings to date, rTMS should be considered as a treatment strategy based on a functional assessment of the severity of upper extremity paralysis (Fugl-Meyer Assessment), and NEURO should be combined with pharmacotherapy, botulinum treatment, and extracorporeal shockwave therapy to maximize therapeutic effects. In the future, it will be important to establish tailormade treatments in which stimulation frequency and sites are adjusted according to the pathological conditions of interhemispheric imbalance, as revealed by functional brain imaging.

Role of cerebral glutamate in post-stroke epileptogenesis

Stroke is one of the most important causes of acquired epilepsy in the adult population. While factors such as cortical involvement and haemorrhage have been associated with increased seizure risk, the mechanisms underlying the development of epilepsy after stroke remain unclear. One hypothesised mechanism is an excitotoxic effect of abnormal glutamate release following a stroke. Cerebral extracellular glutamate levels are known to rise in the setting of acute stroke, and numerous studies have implicated glutamate in the pathogenesis of seizures and epilepsy, both through direct measurement of glutamate from the epileptic brain and by analysis of receptors and transporters central to glutamate homeostasis. While experimental evidence suggests the cellular injury induced by glutamate exposure may lead to development of an epileptic phenotype, there is little direct data linking the rise in glutamate during stroke with the later development of epilepsy. Clinical research in this field has been hampered by the lack of non-invasive methods to measure cerebral glutamate. However, with the increasing availability of 7T MRI technology, Magnetic Resonance Spectroscopy is able to better resolve glutamate from other chemical species at this field strength, and Glutamate Chemical Exchange Saturation Transfer (GluCEST) imaging has been applied to localise epileptic foci in non-lesional focal epilepsy. This review outlines the evidence implicating a pivotal role for cerebral glutamate in the development of post-stroke epilepsy, and exploring the role of MRI in studying glutamate as a biomarker and therefore its suitability as a molecular target for anti-epileptogenic therapies. We hypothesise that the rise in glutamate levels in the setting of acute stroke is a clinically relevant biomarker for the development of post-stroke epilepsy.

Poststroke epilepsy: current perspectives on diagnosis and treatment

Seizures and epilepsy are quite a common outcome of arterial ischemic stroke (AIS) both in pediatric and adult patients, with distinctly higher occurrence in children. These poststroke consequences affect patients' lives, often causing disability. Poststroke seizure (PSS) may also increase mortality in patients with AIS. Early PSS (EPSS) occurring up to 7 days after AIS, late PSS (LPSS) occurring up to 2 years after the onset of AIS, as well as poststroke epilepsy (PSE) can be distinguished. However, the exact definition and cutoff point for PSE should be determined. A wide range of risk factors for seizures and epilepsy after AIS are still being detected and analyzed. More accurate knowledge on risk factors for PSS and PSE as well as possible prediction of epileptic seizures after the onset of AIS may have an impact on improving the prevention and treatment of PSE. The aim of the present review was to discuss current perspectives on diagnosis and treatment of PSS and PSE, both in adult and paediatric patients.

Challenges in Recruitment for the Study of Noninvasive Brain Stimulation in Stroke: Lessons from Deep Brain Stimulation

OBJECTIVE

Noninvasive brain stimulation (NIBS) can augment functional recovery following stroke; however, the technique lacks regulatory approval. Low enrollment in NIBS clinical trials is a key roadblock. Here, we pursued evidence to support the prevailing opinion that enrollment in trials of NIBS is even lower than enrollment in trials of invasive, deep brain stimulation (DBS).

METHODS

We compared 2 clinical trials in stroke conducted within a single urban hospital system, one employing NIBS and the other using DBS, (1) to identify specific criteria that generate low enrollment rates for NIBS and (2) to devise strategies to increase recruitment with guidance from DBS.

RESULTS

Notably, we found that enrollment in the NIBS case study was 5 times lower (2.8%) than the DBS trial (14.5%) (χ(2) = 20.815, P < .0001). Although the number of candidates who met the inclusion criteria was not different (χ(2) = .04, P < .841), exclusion rates differed significantly between the 2 studies (χ(2) = 21.354, P < .0001). Beyond lack of interest, higher exclusion rates in the NIBS study were largely due to exclusion criteria that were not present in the DBS study, including restrictions for recurrent strokes, seizures, and medications.

CONCLUSIONS

Based on our findings, we conclude and suggest that by (1) establishing criteria specific to each NIBS modality, (2) adjusting exclusion criteria based on guidance from DBS, and (3) including patients with common contraindications based on a probability of risk, we may increase enrollment and hence significantly impact the feasibility and generalizability of NIBS paradigms, particularly in stroke.

Seizures and the neurosurgical intensive care unit

The cause of seizures in the neurosurgical intensive care unit (NICU) can be categorized as emanating from either a primary brain pathology or from physiologic derangements of critical care illness. Patients are typically treated with parenteral antiepileptic drugs. For early onset ICU seizures that are easily controlled, data support limited treatment. Late seizures have a more ominous risk for subsequent epilepsy and should be treated for extended periods of time or indefinitely. This review ends by examining the treatment algorithms for simple seizures and status epilepticus and the role newer antiepileptic use can play in the NICU.

Management of seizures following a stroke: what are the options?

Post-stroke seizures are a frequent cause of remote symptomatic epilepsy in adults, especially in older age. About 10% of stroke patients will suffer a seizure, depending on risk factors, such as the type, location and severity of the stroke. Previous stroke accounts for 30-40% of all cases of epilepsy in the elderly. Compared with that in younger patients, the appearance of seizures in old age is less specific and may take time before a diagnosis can be proven. The optimal timing and type of antiepileptic drug (AED) treatment for patients with post-stroke seizures is still a controversial issue. Many population- and hospital-based studies have been performed, ending with generalized recommendations, but still the decision to initiate AED treatment after a first or second seizure should be individualized. Prospective studies in the literature showed that immediate treatment after a first unprovoked seizure does not improve the long-term remission rate. However, because of the physical and psychological influences of recurrent seizures, prophylactic treatment should be considered after a first unprovoked event in an elderly person at high risk of recurrence, taking into consideration the individuality of the patient and a discussion with the patient and his/her family about the risks and benefits of both options. The latest studies regarding post-stroke seizure treatment showed that 'new-generation' drugs, such as lamotrigine, gabapentin and levetiracetam, in low doses would be reasonable because of their high rate of long-term seizure-free periods, improved safety profile, and fewer interactions with other drugs, especially anticoagulant ones, compared with first-generation AEDs. On the other hand, first-generation drugs, such as phenytoin, carbamazepine and phenobarbital, have the potential to have a harmful impact on recovery, bone health, cognition and blood sodium levels and may interact with other treatments used by the elderly population. The drug chosen for use in the elderly population should possess a wide spectrum of activity and have few side effects. An assessment should be done to identify possible drug-drug interactions, the drug should be started at a low dose and titrated slowly to the lowest maintenance dose possible, and enhanced quality of life should be a focus of treatment. So, in the end, further research is needed to determine, more appropriately, the type of AED therapy, timing and duration of treatment.

Hospital-based management of acute ischemic stroke following intravenous thrombolysis

Timely administration of proven therapies remains the primary goal in acute stroke care. Following reperfusion therapy with intravenous thrombolysis, medical and neurological complications may develop in the hospitalized patient with acute ischemic stroke. Medical complications may include deep venous thrombosis, pulmonary embolism, aspiration, systemic infections and neuropsychiatric disturbances. Neurologic complications may include symptomatic intracranial hemorrhage, cerebral edema with elevated intracranial pressure, and post-stroke seizures. Early initiation of preventative strategies and proper management of common complications may improve both short-term and long-term outcomes. Here we review evidence-based management strategies for hospitalized acute ischemic stroke patients following intravenous thrombolysis.

Seizures and epilepsy in patients with a posterior circulation infarct

Seizures occur mainly in patients with cortical infarcts in the anterior circulation. Those related to a posterior circulation infarct (POCI) are considered rare. This study investigated the characteristics of patients with seizures related to a POCI. A total of 180 consecutive patients admitted with a POCI had a 2- to 7-year follow-up; 24 of them (13.6%) developed seizures. Vascular risk factors, etiology and extension of the infarct, degree of neurologic impairment, and outcome were compared in the patients with and without seizures. Complex partial type seizure was the most common presentation. Stroke characteristics were largely the same in the patients with and without seizures. History of a previous stroke was noted in 62.5% of the seizure group and in 17.9% of the nonseizure group (P < .001). Clinical outcome was worse in the seizure group (P = .004). The relative incidence of seizures in patients with a POCI was not lower than that in the overall stroke population. The high incidence of recurrent stroke is the main risk factor for seizures in patients with a POCI. The seizures themselves are responsible for the increased dependence rate.

Short-term outcome of patients with cardiac- and thrombo-embolic cerebral infarcts

OBJECTIVES

It has already been demonstrated by previous studies that patients suffering from a cardiac-embolic stroke (CES) have a worse outcome than those with a thrombo-embolic stroke (TES). Many factors, such as age, initial stroke severity, stroke recurrence and vascular risk factors have been quoted as a possible explanation. The present retrospective study re-investigates more in detail which variables are the most important to explain the difference in disability between patients with CES and with TES on hospital discharge.

PATIENTS AND METHODS

Seven hundred forty-two consecutive patients with a territorial infarct were admitted to the Stroke Unit of the Ghent University Hospital between October 2002 and June 2007. The groups of CES and TES consisted, respectively of 283 and of 459 patients. Age, gender, vascular risk factors including previous strokes and pacemaker implantation, initial stroke severity and outcome, determined by the mean modified Rankin (mR) scale on hospital discharge, were compared between both groups.

RESULTS

Although the hospital stay of the patients with CES and TES was quite similar, the former group was much older with more females, more vascular risk factors, worse neurological deficit on admission and more disability on discharge. On logistic regression analysis coronary artery disease, isolated atrial fibrillation and cardiac valve disorder appear as independent predictors of stroke outcome.

CONCLUSION

The worse outcome in the CES patients is mainly due to the cardiac status of the patients.