De novo status epilepticus with isolated aphasia

Imaging of status epilepticus: Making the invisible visible. A prospective study on 206 patients

BACKGROUND

Peri-ictal MRI abnormalities (PMA) frequently affect the cerebral cortex, hippocampus, pulvinar of the thalamus, corpus callosum, and cerebellum. In this prospective study, we aimed to characterize the spectrum of PMA in a large cohort of patients with status epilepticus.

METHODS

We prospectively recruited 206 patients with SE and an acute MRI. The MRI protocol included diffusion weighted imaging (DWI), fluid-attenuated inversion recovery (FLAIR), arterial spin labeling (ASL), and T1-weighted imaging pre-and post-contrast application. Peri-ictal MRI abnormalities were stratified as either neocortical or non-neocortical. Amygdala, hippocampus, cerebellum, and corpus callosum were regarded as non-neocortical structures.

RESULTS

Peri-ictal MRI abnormalities were observed in 93/206 (45%) of patients in at least one MRI sequence. Diffusion restriction was observed in 56/206 (27%) of patients, which was mainly unilateral in 42/56 (75%) affecting neocortical structures in 25/56 (45%), non-neocortical structures in 20/56 (36%) and both areas in 11/56 (19%) of patients. Cortical DWI lesions were located mostly in frontal lobes 15/25 (60%); non-neocortical diffusion restriction affected either the pulvinar of the thalamus or hippocampus 29/31 (95%). Alterations in FLAIR were observed in 37/203 (18%) of patients. They were mainly unilateral 24/37 (65%); neocortical 18/37 (49%), non-neocortical 16/37 (43%), or affecting both neocortical and non-neocortical structures 3/37 (8%). In ASL, 51/140 (37%) of patients had ictal hyperperfusion. Hyperperfused areas were located mainly in the neocortex 45/51 (88%) and were unilateral 43/51 (84%). In 39/66 (59%) of patients, PMA were reversible in one week. In 27/66 (41%), the PMA persisted and a second follow-up MRI was performed three weeks later in 24/27 (89%) patients. In 19/24 (79%) PMA were resolved.

CONCLUSIONS

Almost half of the patients with SE had peri-ictal MRI abnormalities. The most prevalent PMA was ictal hyperperfusion followed by diffusion restriction and FLAIR abnormalities. Neocortex was most frequently affected especially the frontal lobes. The majority of PMAs were unilateral. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Quantitative Analysis of Diffusion-Restricted Lesions in a Differential Diagnosis of Status Epilepticus and Acute Ischemic Stroke

Background and Purpose

Distinction between acute ischemic stroke (AIS) and status epilepticus (SE) on MRI can be challenging as restricted diffusion may occur in both conditions. In this study, we aimed to test a tool, which could help in differentiating AIS from SE when restricted diffusion was present on MRI.

Materials and Methods

In diffusion weighted imaging (DWI) with a b-value of 1,000 and apparent diffusion coefficient (ADC) maps, we compared the ratios of intensities of gray values of diffusion-restricted lesions to the healthy mirror side in patients with AIS and SE. Patients were recruited prospectively between February 2019 and October 2021. All patients underwent MRI and EEG within the first 48 h of symptom onset.

Results

We identified 26 patients with SE and 164 patients with AIS. All patients had diffusion-restricted lesions with a hyperintensity in DWI and ADC signal decrease. Diffusion restriction was significantly more intense in patients with AIS as compared to patients with SE. The median ratios of intensities of gray values of diffusion-restricted lesions to the healthy mirror side for DWI were 1.42 (interquartile range [IQR] 1.32–1.47) in SE and 1.67 (IQR 1.49–1.90) in AIS (p < 0.001). ADC decrease was more significant in AIS as compared to SE with median ratios of 0.80 (IQR 0.72–0.89) vs. 0.61 (IQR 0.50–0.71), respectively (p < 0.001). A cutoff value for ratios of DWI signal was 1.495 with a sensitivity of 75% and a specificity of 85%. Values lower than 1.495 were more likely to be associated with SE and higher values were with AIS. A cutoff value for ADC ratios was 0.735 with a sensitivity of 73% and a specificity of 84%. Values lower than 0.735 were more likely to be associated with AIS and higher values were with SE.

Conclusion

Diffusion restriction and ADC decrease were significantly more intense in patients with AIS as compared to SE. Therefore, quantitative analysis of diffusion restriction may be a helpful tool for differentiating between AIS and SE when restricted diffusion is present on MRI.

Aphasic status epilepticus after glioma resection: two case reports

Aphasic status epilepticus (ASE) is a subtype of focal nonconvulsive status epilepticus, in which language disturbance is the only objective clinical manifestation. We present two cases of patients who experienced delayed onset of temporal aphasia after the removal of glioma at the language-dominant hemisphere. In both cases, arterial spin labeling was useful for diagnosis and antiepileptic drug was effective. ASE should be considered a cause of persistent aphasia after glioma resection at or near the language area.

Epileptic aphasia - A critical appraisal

INTRODUCTION

Aphasic and other language disturbances occur in patients with epilepsy during and after epileptic seizures. Moreover, the interictal language profile in these patients is heterogeneous, varying from normal language profile to impairment in different language functions. The aim of this paper was to critically review the terms and concepts of ictal language alterations.

MATERIAL AND METHOD

For this review we performed an extensive literature search on the term "epileptic aphasia" and analyzed the semiology and terminology indicating language-associated seizure symptoms. In addition, we give an overview on EEG, etiology, and brain imaging findings and ictal language disorders.

RESULTS

In the literature, a plethora of terms indicates language-associated seizure symptoms. Simultaneous Video-EEG monitoring represents the gold standard to correctly classify ictal versus postictal language disturbances and to differentiate aphasic symptoms from speech automatisms. Different rhythmic and periodic EEG patterns associated with ictal language disturbances are recognized. Cerebral magnetic resonance imaging (cMRI) is essential in the diagnosis of seizures and epilepsy. Brain tumors and acute or remote cerebrovascular lesions are the most frequently reported structural etiologies underlying ictal language alterations. However, it has to be recognized that brain imaging may show alterations being the consequence of seizures itself rather than its cause. Functional brain imaging might be informative in patients with inconclusive EEG and MRI findings. Overall, seizure-associated aphasia is reported to have good lateralizing significance.

CONCLUSION

Various language disturbances are caused by different types of seizures, epilepsies and underlying etiologies. In the clinical context, simultaneous Video-EEG monitoring facilitates precise classification of ictal versus postictal language alterations and differentiation of aphasic symptoms from speech automatisms.

Aphasic status epilepticus of frontal origin treated by resective surgery

Aphasic status epilepticus (SE) is a clinical entity of SE, but it has not been well recognized. We report a 43-year-old female with a chronic drug-resistant epilepsy with aphasic SE, treated by resective surgery. The patient showed long-lasting weekly episodes of hypokinesia, slow verbal response, and dysphasia, which were diagnosed as symptoms of aphasic SE. Magnetic resonance imaging showed encephalomalacia in the left frontal lobe with a hemosiderin rim. Intracranial electroencephalography revealed continuous spikes, predominantly on the left superior frontal gyrus with hemosiderin deposit. The aphasic symptoms were seen when ictal discharges gradually spread to the wide area of the left anterior frontal lobe, including the language area. The episodes of recurrent aphasic SE had disappeared by one year after the left anterior frontal resection. We should consider aphasic SE when language impairment is episodic, and consider surgical intervention in cases where it repeatedly occurs despite appropriate medical therapy.

•

Long-lasting slow verbal response and dysphasia could be manifestations of aphasic status epilepticus of frontal origin

•

Epilepsy surgery should be considered for repeat aphasic SE under appropriate medical treatment after definite diagnosis

•

Precise time correlations between aphasic symptoms and ictal discharges could be unclear even by intracranial electroencephalography.

Lateralized periodic discharges in insular status epilepticus: A case report of a periodic EEG pattern associated with ictal manifestation

•

Focal status epilepticus has to be considered in the differential diagnosis of patients presenting with aphasia, even in the absence of previous history of epilepsy.

•

Aphasia can be a rare presenting sign of insular lobe epilepsy.

•

Lateralized periodic discharges could represent an EEG ictal pattern.

Objective

Insular lobe seizures generally represent a misconceived ictal phenomenon characterized by specific neurological signs. Aphasia can be a rare presenting sign associated with insular lobe epilepsy which could be easily mistaken for a manifestation of other acute brain diseases.

Method

We describe an insular status epilepticus (SE) characterized by sudden onset of language disturbance associated with hypersalivation and paraesthesia. A concomitant EEG recording showed the presence of Lateralized Periodic Discharges plus superimposed fast activity (LPDs + F). After an adequate acute endovenous anti-seizure treatment, a normalization of the EEG abnormalities with a complete resolution of all the neurological symptoms was achieved.

Discussion

Language disturbances can be usually found in various pathological acute pictures involving the dominant frontal and temporal lobes. The presence of certain EEG pattern, could rise the suspect of aphasia as a critical manifestation. LPDs pattern is usually correlated with structural lesions. The association between LPDs and seizure is controversial but it seems to be more consistent when they are associated with “Plus modifiers” and with an high periodic frequency.

Conclusion

Our case underlines the importance of considering focal SE in the differential diagnosis of patients presenting aphasia, even in the absence of previous history of epilepsy. We describe how LPDs can be associated with SE in a patient affected by a brain tumour, supporting the idea that some characteristic periodic patterns could be associated with seizure occurrence.

A Rare Case of Prolonged Ictal Aphasia

Aphasia is commonly seen in focal brain lesions. Prolonged aphasia from an ictal state is rarely reported. We report the case of a 62-year-old man with focal motor status epilepticus manifested initially as episodic right cheiro-oral clonic movements with preserved awareness and expressive aphasia for 48 hours. EEG showed left frontal and central lateralized periodic discharges (LPDs) without plus features (rhythmicity, overlying fast) and electrographic seizures that correlated with right clonic movements. Treatment with two seizure medications (levetiracetam and lacosamide) resulted in complete electrographic and clinical resolution of his symptoms, including aphasia. In this case, aphasia was determined to be an ictal semiology, as patient had complete resolution of his symptoms supported by a normal EEG after receiving seizure medications. We suggest keeping high suspicion for an ictal process in patients with sudden-onset aphasia supported by EEG findings of LPDs.

Aphasic status epilepticus as the sole symptom of epilepsy: A case report and literature review

Aphasia is a common symptom encountered by neurologists. However, the presence of aphasia as the sole manifestation of partial status epilepticus is rare. The present study reports a case of aphasic status epilepticus in a 27-year-old right-handed female who presented after the abrupt onset of aphasia, which had persisted for 1.5 days. The patient's medical history included head trauma followed by a craniectomy and cranioplasty. Computed tomography scans revealed a lesion in the patient's left parietal lobe, and an electroencephalogram showed a spike and slow wave pattern in the left hemisphere of the brain during aphasia. The patient's condition improved after the oral administration of oxcarbazepine daily. In the present study it was observed that EEGs were a simple method to diagnose aphasic seizures and therefore EEG recordings should be performed in all cases of unexplained aphasia. In addition, the present study reviewed previously reported cases of aphasic status epilepticus.

An exploration of the spectrum of peri-ictal MRI change; a comprehensive literature review

PURPOSE

The aim of this review was to identify published studies in the literature relating to ictal induced MRI change and to identify certain common themes, practical points for clinicians and areas for future research.

METHODS

We identified 96 articles that satisfied our inclusion criteria yielding 575 cases. All articles were analysed; number of subjects, spectrum of MRI and EEG change, aetiology, and follow-up (both clinical and imaging) were noted.

RESULTS

The most frequent imaging changes were restricted diffusion, T2-hyperintensity and reduced ADC values. The mesial temporal structures and neocortex were most commonly affected locations though subcortical structures like the thalamus and pulvinar were also described. Practical clinical points included; the development of PLEDS concordant with ictal imaging change was associated with worse clinical prognosis, patients with seizures due to symptomatic aetiology may be more likely to develop ictal related imaging change and follow up is vitally important to ensure that ictal related oedema is not misidentified as a mass lesion or conversely that a mass lesion is not misidentified as ictal related change.

CONCLUSION

Qualitative MRI studies have provided clinicians with useful in-vivo insights into the dynamic ictal neuronal environment. Changes are not only localised to the ictal focus but can be remote and irreversible. Small patient numbers varying study design and high numbers of symptomatic seizures makes comparison between studies problematic. Also there is possible microstructural quantitative MRI changes that are missed on qualitative MRI. There is a need for prospective quantitative MRI studies in patients with epilepsy peri-icatlly with a uniform period of follow up and comparison to control data.

Emergency electroencephalogram: Usefulness in the diagnosis of nonconvulsive status epilepticus by the on-call neurologist

INTRODUCTION

We aim to describe the use of emergency electroencephalogram (EmEEG) by the on-call neurologist when nonconvulsive status epilepticus (NCSE) is suspected, and in other indications, in a tertiary hospital.

SUBJECTS AND METHODS

Observational retrospective cohort study of emergency EEG (EmEEG) recordings with 8-channel systems performed and analysed by the on-call neurologist in the emergency department and in-hospital wards between July 2013 and May 2015. Variables recorded were sex, age, symptoms, first diagnosis, previous seizure and cause, previous stroke, cancer, brain computed tomography, diagnosis after EEG, treatment, patient progress, routine control EEG (rEEG), and final diagnosis. We analysed frequency data, sensitivity, and specificity in the diagnosis of NCSE.

RESULTS

The study included 135 EEG recordings performed in 129 patients; 51.4% were men and their median age was 69 years. In 112 cases (83%), doctors ruled out suspected NCSE because of altered level of consciousness in 42 (37.5%), behavioural abnormalities in 38 (33.9%), and aphasia in 32 (28.5%). The EmEEG diagnosis was NCSE in 37 patients (33%), and this was confirmed in 35 (94.6%) as the final diagnosis. In 3 other cases, NCSE was the diagnosis on discharge as confirmed by rEEG although the EmEEG missed this condition at first. EmEEG performed to rule out NCSE showed 92.1% sensitivity, 97.2% specificity, a positive predictive value of 94.6%, and a negative predictive value of 96%.

CONCLUSIONS

Our experience finds that, in an appropriate clinical context, EmEEG performed by the on-call neurologist is a sensitive and specific tool for diagnosing NCSE.