Ebru Altindag

Are There Any Specific EEG Findings in Autoimmune Epilepsies

This study evaluated the EEG findings of patients whose seizures were associated with a possible autoimmune etiology. Our aim was to find clues to distinguish patients with antineuronal antibodies (Ab) through EEG studies. We reviewed our database and identified antineuronal Ab positive epilepsy patients with or without autoimmune encephalitis. These patients had Abs to N-methyl-d-aspartate receptor (NMDAR) (n = 5), glycine receptor (GLY-R) (n = 5), contactin-associated protein-like 2 (CASPR-2) (n = 4), uncharacterized voltage-gated potassium channel complex (VGKC) antigens (n = 2), glutamic acid decarboxylase (GAD) (n = 2), Hu (n = 1), and amphiphysin (n = 1). The control group consisted of 21 seronegative epilepsy or encephalopathy patients with similar clinical features. EEG findings were compared between the groups in a blindfolded design. We did not find any significant difference in EEG findings between antineuronal Ab positive epilepsy patients and seronegative control group. It was remarkable that four seropositive but none of the seronegative patients presented with nonconvulsive status epilepticus (NCSE) or focal motor status epilepticus. Continuous theta and delta rhythms were observed in 5 (71%) seropositive patients with autoimmune encephalitis and 2 (25%) seronegative patients. Eight (40 %) seropositive patients showed a frontal intermittent rhythmic delta activity (FIRDA) pattern as opposed to 5 (24%) seronegative patients. Two patients with NMDAR Ab positivity showed rhythmic delta waves superimposed with beta frequency activity resembling “delta brush” pattern. EEG seems as a limited diagnostic tool in differentiating epilepsy and/or encephalopathy patients with a possible autoimmune etiology from those without. However, antineuronal Abs associated with encephalitis should be considered in the etiology of status epilepticus forms. A possible autoimmune etiology for seizures may be considered in the presence of continuous slow waves, FIRDA, and delta brush pattern in the EEG.

Does semiology tell us the origin of seizures consisting mainly of an alteration in consciousness

Purpose:  Studies on seizures only with an alteration of consciousness were limited mainly to generalized epilepsy. This seizure type has been described rarely in focal epilepsy. We aimed to analyze the semiologic features of this seizure type in focal and generalized epilepsies in a blinded design.

MR spectroscopy findings in Lafora disease.

Our aim was to investigate the [1H] MR spectroscopy (MRS) findings of Lafora Disease (LD), which is a disabling form of progressive myoclonic epilepsy.

Magnetic Resonance Spectroscopy Findings in Photosensitive Idiopathic Generalized Epilepsy

Studies investigating the pathophysiology of epileptic photosensitivity indicate variable involvement of particular brain regions. Our aim was to identify metabolic differences between photosensitive idiopathic generalized epilepsy (IGE) patients and nonphotosensitive IGE patients and normal healthy subjects by using Magnetic Resonance Spectroscopy (MRS). Fourteen patients diagnosed with photosensitive IGE were investigated. The control groups consisted of 14 age- and sex-matched healthy volunteers and 14 IGE patients without photosensitivity. MRS measurements of N-acetylaspartate (NAA), choline-containing compounds (Cho), creatine (Cr) were performed in the frontal and occipital cortex and the thalamus bilaterally using a stimulated echo acquisition mode (STEAM) technique with a voxel size of 20times20times20 mm. The values of the patients with IGE were compared with those of the normal controls and within subgroups according to the clinical variables by appropriate statistical tests. Photosensitive IGE patients showed significantly decreased concentrations of NAA in the right frontal lobe and left thalamus, decreased NAA/Cr ratio in left thalamus and significantly increased concentrations of Cho/Cr ratio in the right frontal lobe and NAA/Cr in the left occipital lobe when compared to normal controls. Furthermore, left occipital NAA concentration increased and left thalamus NAA/Cr ratios were decreased from the IGE patients without photosensitivity but without reaching statistical significance. Our results support previous MR studies suggesting an asymmetrical neuronal dysfunction in favor of the dominant occipital cortex and thalamus in photosensitive IGE patients.

Electroencephalographic Patterns Recorded by Continuous EEG Monitoring in Patients with Change of Consciousness in the Neurological Intensive Care Unit

INTRODUCTION Our aim was to examine the frequency of various electrographic patterns including periodic discharges (PD), repetitive spike waves (RSW), rhythmic delta activities (RDA), nonconvulsive seizures (NCS) and nonconvulsive status epilepticus (NCSE) in continuous EEG monitoring (cEEG) of the critically ill patients with change of consciousness and the presence of specific clinical and laboratory findings associated with these important patterns in this study. METHODS Patients with changes of consciousness in the neurological intensive care unit (NICU) were consecutively monitored with cEEG during 2 years. Their clinical, electrophysiological, radiological and laboratory findings were evaluated retrospectively. RESULTS This sample consisted of 57 (25 men) patients with a mean age of 68.2 years. Mean duration of cEEG monitoring was 2532.6 minutes. The most common electrographic patterns were PD (33%) and NCS-NCSE (26.3%). The presence of NCS-NCSE was significantly associated with PD (57.9%, p<0.001). PD and NCS-NCSE were the mostly seen in patients with acute stroke and hypoxic encephalopathy. Duration of monitoring was significantly longer in the group with PD and NCS-NCSE (p:0.004, p:0.014). Detection of any electrographic pattern in EEG before monitoring was associated with the presence of any pattern in cEEG (59.3%, p<0.0001). Convulsive or nonconvulsive seizure during monitoring was common in patients with electrographic patterns (p<0.0001). 66.7% of NCS-NCSE was seen within the first 12 hours and 26.7% was seen within the 12-24 hours of the monitoring. CONCLUSION Detection of any electrographic pattern in EEG before monitoring was associated with the presence of any important pattern in cEEG monitoring. This association suggest that at least 24 hours-monitoring of these patients could be useful for the diagnosis of clinical and/or electrographic seizures.

Delta Brush Pattern Is Not Unique to NMDAR Encephalitis: Evaluation of Two Independent Long-Term EEG Cohorts

Purpose. Although its specificity has not previously been investigated in other cohorts, delta brush pattern (DBP) is increasingly reported in the EEGs of patients with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. Methods. We aimed to investigate the DBP in the EEGs of 2 cohorts; patients with change in consciousness for various causes monitored in the intensive care unit (ICU) (n = 106) and patients with mesial temporal lobe epilepsy (MTLE) with or without antineuronal antibodies (n = 76). Results. These patients were investigated for the presence of DBP, defined as an EEG pattern characterized by delta activity at 1 to 3 Hz with superimposed bursts of rhythmic 12- to 30-Hz activity. Two investigators blindfolded for the clinical and immunological data independently analyzed the EEGs for recognition of this pattern. An EEG picture compatible with DBP was observed in 4 patients; only 1 of them (1.3%) belonged to the MTLE group. She did not bear any of the investigated autoantibodies and was seizure-free after epilepsy surgery. In the ICU group, there were 3 additional patients showing DBP with various diagnoses such as hypoxic encephalopathy, brain tumor, stroke, and metabolic derangements. All of them had died in 1-month period. Conclusions. Our results underlined that DBP is not unique to NMDAR encephalitis; it may very rarely occur in MTLE with good prognosis after surgery and second, in ICU patients who have high mortality rate. Therefore, the presence of this pattern should alert the clinician for NMDAR encephalitis but other possible etiologies should not be ignored.

Reevaluation of the Critically Ill Patients With Nonconvulsive Status Epilepticus by Using Salzburg Consensus Criteria

Objective. We aimed to assess the usefulness of the Salzburg Consensus Criteria (SCC) for determining the prognosis of critically ill patients with nonconvulsive status epilepticus (NCSE). Methods. We retrospectively reviewed consecutive patients with unconsciousness followed up in the intensive care unit (ICU). Three clinical neurophysiologists, one of them blinded to clinical and laboratory data, reevaluated all EEG data independently and determined NCSE according to SCC. The incidence of NCSE and ictal EEG patterns and their relationship to clinical, laboratory, neuroradiological, and prognostic findings were assessed. Results. A total of 107 consecutive patients with mean age 68.2 ± 15.3 years (57 females) were enrolled in the study. Primary neuronal injury was detected in 59 patients (55.7%). Thirty-three patients (30.8%) were diagnosed as NCSE. While authors decided to treat 33 patients (30.8%), 32 patients (29.9%) had been treated in real-life evaluation. Clinical and EEG improvement were detected in 12 patients (11.3%) in real-life treatment group showing correlation with lack of intubation and ICU stay related to postsurgical event. Rate of mortality (45.8%) was high showing association with systemic-metabolic etiology, severity of coma and presence of “plus” modifiers in the EEG. Conclusion and Significance. Our findings suggest that SCC is highly compatible with clinical practice in the decision for treatment of patients with NCSE. The presence of “plus” modifiers in the EEG was found to be associated with mortality in these patients and was a significant marker for the high mortality rate.

IMPULSIVITY IN ALZHEIMER’S DISEASE AS DETECTED BY D-CPT

Background: Genetic studies identified an association between Alzheimer’s disease (AD) and common polymorphisms in the MS4A and TREM loci, each containing cluster of homologous genes. Methods:We searched for rare coding variants in 15 genes mapped to these loci by next generation sequencing of a North American dataset (210 cases and 233 controls). Results:Analysis of the MS4A gene-cluster revealed loss-of-function variants in 6 controls and 3 cases. Investigation of the TREM gene-cluster detected known AD associated TREM2 substitutions (p.R47H, p.D87N and p.H157Y) affecting both TREM2 isoforms (NM_018965 and NM_001271821). We also identified two cases with novel TREM2 variants (p.L205P and p.G219C), which mapped only to the isoform NM_001271821. A p.S248R substitution in the homologous TREML2 gene was detected in 5 controls and 1 case suggesting a protective effect (pooled p-value 1⁄4 0.033). Conclusions:Our study advocates for the importance of mutation analysis of controls, particularly for GWAS loci containing SNPs with a minor allele frequency higher in controls versus cases (e.g. MS4A locus), to search for functional variants with a protective effect.

Steroid-Responsive Late Symptomatic Perihematomal Edema in Intracerebral Hemorrhage

Correspondence Address: Dr. Selen Gur Ozmen, Istanbul Universitesi, Deneysel Tip ve Arastirma Enstitusu (DETAE), Sinirbilim Anabilim Dali, Istanbul, Turkiye E-mail: drselenozmen@gmail.com Received: 06.08.2014 Accepted: 06.09.2014 1Unit of Stroke Rehabilitation and Research, Memorial Şisli Hospital, Istanbul, Turkey 2Clinic of Neurology, Igdir State Hospital, Igdir, Turkey 3Unit of Intensive Care, Memorial Hizmet Hospital, Istanbul, Turkey 4Clinic of Neurology, Florence Nightingale Hospital, Istanbul, Turkey 5Unit of Acute Stroke, Memorial Hizmet Hospital, Istanbul, Turkey Letter to the Editor