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Introduction.Although ictal blinking is significantly more frequent in generalized epilepsy, it has been reported as a rare but useful lateralizing sign in focal seizures when it is not associated with facial clonic twitching. This study aimed to raise awareness of eye blinking as a semiological lateralizing sign. Method.Our database over an 11-year period reviewed retrospectively to assess patients who had ictal blinking associated with focal seizures. Results.Among 632 patients, 14 (2.2%), who had 3 to 13 (7 ± 3) seizures during video-EEG monitoring, were included. Twenty-five percent of all 92 seizures displayed ictal blinking and each patient had one to five seizures with ictal blinking. Ictal blinking was unilateral in 17%, asymmetrical in 22% and symmetrical in 61%. The blinking appeared with a mean latency of 6.3 s (range 0-39) after the clinical seizure-onset, localized most often to fronto-temporal, then in frontal or occipital regions. Blinking was ipsilateral to ictal scalp EEG lateralization side in 83% (5/6) of the patients with unilateral/asymmetrical blinking. The exact lateralization and localization of ictal activity could not have been determined via EEG in most of the patients with symmetrical blinking, remarkably. Conclusions.Unilateral/asymmetrical blinking is one of the early components of the seizures and appears as a useful lateralizing sign, often associated with fronto-temporal seizure-onset. Symmetrical blinking, on the other hand, did not seem to be valuable in lateralization and localization of focal seizures. Future studies using invasive recordings and periocular electrodes are needed to evaluate the value of blinking in lateralization and localization.

Photosensitive occipital lobe epilepsy (POLE) should be suspected in patients with occipital lobe seizures triggered by photic stimuli, who have normal motor‐mental development and brain imaging. We aimed to examine the clinical, electrophysiological, and prognostic features of POLE, which is a rare and under‐investigated syndrome. Archives from two tertiary epilepsy centers were retrospectively scanned and patients with normal neurological examination and cranial imaging were identified with POLE if they had: (1) seizures consistently triggered by photic stimuli; (2) non‐motor seizures with visual symptoms; and (3) photosensitivity documented on EEG. The clinical and electrophysiological features and prognostic factors were evaluated for patients who had follow‐up ≥5 years. We identified 29 patients diagnosed with POLE with a mean age of 20.1 ± 7.6 years. In one‐third of the patients, POLE syndrome overlapped with genetic generalized epilepsy (GGE). The overlap group had higher rates of febrile seizure history and self‐induction; when compared to pure POLE patients, their EEGs showed more frequent interictal generalized epileptic discharges and posterior multiple spikes during intermittent photic stimulation. During long‐term follow‐up, the remission rate for POLE was 80%, but EEG photosensitivity persisted in three quarters of patients despite clinical remission, and more than half had relapsed after clinical remission. This first long‐term follow‐up study, utilizing newly suggested criteria of the International League Against Epilepsy, showed that POLE syndrome shows a notable overlap with GGE but also has distinctive features. POLE has a good prognosis; however, relapses are common, and photosensitivity persists as an EEG finding in the majority of patients.

Lafora disease (LD) is a severe form of progressive myoclonus epilepsy inherited in an autosomal recessive fashion. It is associated with biallelic pathogenic variations in EPM2Aor NHLRC1, which encode laforin and malin, respectively. The disease usually starts with adolescent onset seizures followed by progressive dementia, refractory status epilepticus and eventually death within 10 years of onset. LD is generally accepted as having a homogenous clinical course with no considerable differences between EPM2Aor NHLRC1associated forms. Nevertheless, late-onset and slow progressing forms of the disease have also been reported. Herein, we have performed clinical and genetic analyses of 14 LD patients from 12 different families and identified 8 distinct biallelic variations in these patients. Five of these variations were novel and/or associated with the LD phenotype for the first time. Interestingly, almost half of the cases were homozygous for the rare rs769301934 (NM_198586.3(NHLRC1): c.436 G > A; p.(Asp146Asn)) allele in NHLRC1. A less severe phenotype with an onset at a later age may be the reason for the biased inflation of this variant, which is already present in the human gene pool and can hence arise in the homozygous form in populations with increased parental consanguinity.

AimsThe pathophysiology of switch‐of lateralization and bilateral temporal asynchrony, which are scalp EEG ictal propagation patterns (iPP) in temporal lobe epilepsy (TLE), is poorly understood. We aimed to analyse functional connectivity (FC) of the temporal lobe and related areas in patients with TLE with iPP (iPP‐TLE) and without iPP (non‐iPP TLE). MethodsTwelve patients with iPP‐TLE, 13 patients with non‐iPP TLE, and 13 healthy controls (HC) underwent resting‐state functional MRI (fMRI). Seed‐based FC was analysed between the homologous insulae, hippocampi, amygdalae, parahippocampal, superior temporal, and middle temporal gyri. ResultsFC was reduced between homologous temporal lobe areas in patients with TLE compared with HCs. Patients with non‐iPP TLE displayed decreased FC between the homologous parahippocampal and superior temporal gyri, and patients with iPP‐TLE had lower FC between the homologous insulae, parahippocampal and superior temporal gyri compared with HC. Furthermore, patients with iPP‐TLE tended to have lower FC between the bilateral insulae when compared with patients with non‐iPP TLE. ConclusionsReduced FC of interhemispheric connections between temporal lobes and related areas might be an adaptive change to protect contralateral areas in seizure propagation. The insula showed decreased FC between two hemispheres in patients with iPP‐TLE, assuming a role in ictal scalp propagation pattern changes in TLE.

Objective: We aimed to determine the therapeutic drug monitoring (TDM) features and the relation to Brain-Derived Neurotrophic Factor (BDNF) of frequently used new antiepileptic drugs (NADs) including lamotrigine (LTG), oxcarbazepine (OXC), zonisamide (ZNS) and lacosamide (LCM). Moreover, we investigated their effect on the quality of life (QoL). Methods: Eighty epileptic patients who had been using the NADs, and thirteen healthy participants were included in this cross-sectional study. The participants were randomized into groups. The QOLIE-31 test was used for the assessment of QoL. We also prepared and applied "Safety Test". HPLC method for TDM, and ELISA method for BDNF measurements were used consecutively. Results: In comparison to healthy participants, epileptic participants had lower marriage rate (p=0.049), education level (p<0.001), alcohol use (p=0.002). BDNF levels were higher in patients with focal epilepsy (p=0.013) and in those with higher education level (p=0.016). There were negative correlations between serum BDNF levels and serum ZNS levels (p=0.042) with LTGpolytherapy, serum MHD levels (a 10-monohydroxy derivative of OXC, p=0.041) with OXCmonotherapy. There was no difference in BDNF according to monotherapy-polytherapy, drugresistant groups, regarding seizure frequency. There was a positive correlation between total health status and QoL (p<0.001). QOLIE-31 overall score (OS) was higher in those with OXC-monotherapy (76.5±14.5). OS (p<0.001), seizure worry (SW, p=0.004), cognition (C, p<0.001), social function (SF, p<0.001) were different in the main groups. Forgetfulness was the most common unwanted effect. Conclusion: While TDM helps the clinician to use more effective and safe NADs, BDNF may assist in TDM for reaching the therapeutic target in epilepsy.

Interictal focal EEG features were frequently observed in generalized, epilepsies, but there is limited information about interictal, epileptiform/nonepileptiform generalized paroxysms in focal epilepsies. We aimed to report the frequency and associated factors of generalized EEG discharges in focal epilepsy with unknown cause (FEUC) and mesial, temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). A total of 200 patients (FEUC in 90 patients; MTLE-HS in 110 patients) were included. Generalized epileptiform (spike/sharp waves simultaneously in all regions) and nonspecific generalized discharges (paroxysmal slow waves) were investigated. All clinical and laboratory findings of 2 groups were compared with each other and with remaining control group, without generalized paroxysms, statistically. Generalized EEG features were present in 22 (11%; 4 males) patients; 9 in the FEUC group (10%; 2) and 13 in the MTLE-HS group (11.8%). Female gender (P< .021), febrile seizure (P< .034), precipitant factors (P< .025), and parental consanguinity (P< .033) were significantly higher in the group with generalized EEG findings. Monotherapy rates were lower in the MTLE-HS group (P< .05). The relationship of generalized EEG features with female gender and parental consanguinity may point out to a genetic property among focal epilepsies, while the relationship with febrile seizures and precipitant factors may be a clue about mechanisms with more extensive involvement of the neuronal networks.

Aims. In addition to a complex inheritance pattern in genetic generalized epilepsy (GGE) syndromes, some studies have recently identified SLC2A1variants which lead to glucose transporter type 1 (GLUT1) defects, in patients diagnosed with GGE. Here, we investigated the possible role of SLC2A1variants in GGE patients with eyelid myoclonia (EM) which is a rare generalized seizure type associated with drug resistance and cognitive dysfunction. Methods. After polymerase chain reaction with designed primers, sequencing of all SLC2A1exons was performed for 25 GGE‐EM patients, as well as a control group of 15 GGE patients with absence seizures. Results. Although various single nucleotide polymorphisms clustered in the ninth exon were detected, no variant was found in the two groups with GGE. Conclusions. Even though the patient number in this study is small, the data suggest that SLC2A1variants do not play any causative role in GGE associated with EM.

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.

Lipoid proteinosis (LP) is a rare autosomal recessive disease characterized by deposition of hyaline material in skin and mucosae. Epilepsy, as an extracutaneous manifestation associated with typical mesial temporal calcifications, has already been identified, but its characteristics and long-term prognosis have not been thoroughly investigated. We included 7 consecutive patients with LP with typical intracranial calcifications out of 16 patients with ECM1mutations and investigated the semiologic features, ictal and interictal EEG findings, and long-term prognosis of epilepsy in this genodermatosis. Four of them had seizures (57.1%), and focal seizures with motionless staring were the most common seizure phenotype, originating from bilateral mesial temporal areas, but interictal spikes were scant. Auras were observed in three patients, mostly as epigastric sensation and déjà vu, which indicated mesial temporal lobe origin. Three patients with homozygous mutations in sixth and seventh exons of the ECM1gene had a drug-resistant course at the end of long-term follow-up. Molecular genetic testing showed a rare compound heterozygous mutation in one patient, which was also associated with seizures but without drug-resistance. Our findings indicated a spectrum for epilepsy with a desperate drug-resistant course for decades in most patients with LP, which is still an underrecognized disease by neurologists.

Introduction.Sudden unexpected death in epilepsy (SUDEP) is a major cause of death in patients with chronic drug-resistant epilepsy, and peri-ictal prone position has been elucidated as a risk factor for SUDEP. We aimed to investigate consecutive patients in peri-ictal prone positions in our video EEG monitoring (VEM) unit and compare patients with and without peri-ictal prone position to emphasize its relationship with other independent risk factors for SUDEP. Methods.We retrospectively screened all patients with peri-ictal prone position who underwent VEM for a 10-year period and these patients constituted the prone (+) group. All patients without peri-ictal prone position who underwent VEM in the past 2 years constituted the prone (−) control group. Sequences of peri-ictal positions and interventions were evaluated. Clinical and laboratory features and SUDEP-7 scores were compared between the groups. Results.A total of 21 seizures were identified with peri-ictal prone position from 16 patients. SUDEP-7 scores were significantly higher in the prone (+) group. Longer duration of epilepsy, early age at seizure onset, mental retardation, and frequency of seizures of any type (>50 seizures per month for the past year) were found significantly different between the prone (+) and prone (−) groups. Conclusion.Peri-ictal prone position in the VEM unit may relate with other independent risk factors of SUDEP, especially with mental retardation. Nocturnal supervision becomes important to reduce SUDEP risk, especially in patients with mental retardation.

There have been recent reports of antibody-mediated status epilepticus. The objective of our study was to investigate the prevalence of neuronal autoantibodies in patients with status epilepticus (SE) with unresolved etiology. The presence of neuronal autoantibodies was investigated prospectively in adult patients with SE who presented to our clinic between February 2012 and December 2013 with unresolved etiology. Clinical and electrophysiologic features of seropositive patients were recorded. Also, seronegative and seropositive patient groups were compared in terms of demographic and clinical features, treatment responses, and outcomes. Neuronal antibodies against N-methyl-d-aspartate receptor (NMDA-R) were positive in 2 patients, against glycine receptor (Gly-R) in 2 patients, and against gamma-aminobutyric acid-A receptor [GABA(A)R] in 1 patient, which constituted a total of 5 (22.7%) of 22 patients with SE with unidentified etiology. One of three patients with systemic tumors was positive for GABA(A)R antibody. Four patients had a short epilepsy duration, while one of the NMDA-R antibody-positive patients had chronic epilepsy and double cortex finding in MRI. There was no significant difference between seropositive and seronegative patient groups in terms of demographic and clinical features, treatment responses, and outcomes. Neuronal antibodies are found in a sizeable portion of de novo SE patients, who are potential candidates of autoimmune encephalitis. Alternatively, these antibodies may presumably also emerge in SE patients with a chronic epilepsy history as an epiphenomenon. Further research is required to make the distinction between these two different antibody formation mechanisms.

Purpose. There is a lack of knowledge on consecutive patients with epilepsy associated with bilateral hippocampal sclerosis (BHS). We aimed to investigate the differentiating features of BHS in comparison with unilateral HS (UHS). Method. We investigated our database for patients with epilepsy fulfilling the major magnetic resonance imaging criteria for BHS; namely, presence of bilateral atrophy and high signal changes on T2 and FLAIR series in the hippocampi. UHS patients seen in past 2 years were included as the control group. Clinical, EEG, and other laboratory findings, data on treatment response and epilepsy surgery were investigated from their files. Results. A total of 124 patients (31 with BHS and 93 with UHS; 49 right-sided and 44 left-sided) were included. We found that 16.1% of the BHS and 18.3% of the UHS groups were not drug-refractory. A binary logistic regression analysis performed with significant clinical features disclosed that history of febrile status epilepticus, mental retardation, and status epilepticus were statistically more common in BHS group. Moreover, diagnosis of psychosis established by an experienced psychiatrist and slowing of the EEG background activity were both found significantly more frequent in BHS. 66.67% of the operated BHS patients showed benefit from epilepsy surgery. Conclusions. BHS is a heterogeneous group, showing significant differences such as increased frequencies of mental retardation, status epilepticus, febrile status epilepticus and psychosis, in comparison to UHS. In all, 16.1% of the BHS cases showed a benign course similar to the UHS group and some patients with drug-resistant epilepsy may show benefit from epilepsy surgery.

Eyelid myoclonia (EM) with or without absences are a rare type of generalized seizures associated with a variety of epilepsy syndromes with an unknown pathophysiology. The aim of this study was to investigate the possible contribution of the brainstem structures in this underrecognized special type of seizures. Sixteen consecutive patients with EM, diagnosed with genetic generalized epilepsy (GGE) according to International League Against Epilepsy 2010 criteria were included. Brainstem excitabilities were examined by blink reflex (BR) studies. The results of BR studies in GGE patients with EM were statistically compared with 2 control groups; namely age- and gender-matched healthy volunteers and juvenile myoclonic epilepsy (JME) patients without any absences and using similar antiepileptic drugs. There were no statistical differences between the thresholds of the BR studies and the BR recovery curves in terms of amplitudes and areas of healthy subjects, JME patients and GGE patients with EM. Our findings do not support a profound interictal hyperexcitability in the BR-related brainstem structures of the GGE patients with EM. It can be considered that EM may be associated with excitability changes of the occipital cortex and other cortical areas.

Backgrand. Lateralized periodic discharges (LPDs) are infrequent electroencephalograph (EEG) findings, and may present in ictal or interictal form. They are regarded as potential electrophysiologic signs of convulsive or nonconvulsive status epilepticus (NCSE). We report four patients who presented with NCSE and one who presented with convulsive status epilepticus in the postictal period, characterized by LPDs in EEG recordings in the first year after stroke.

NEDD4-2 alias NEDD4L (neural precursor cell expressed, developmentally downregulated) gene was reported as a candidate gene for epileptic photo-sensitivity. We aimed to investigate this possible association of NEDD4-2 variants with idiopathic photosensitive epilepsy. Consecutive patients who had been followed up at our epilepsy center and diagnosed with idiopathic epilepsy according to ILAE criteria and clear-cut photoparoxysmal responses in their electroencephalograms and 100 ethnically matched healthy subjects were included in the study. The regions around previously reported three variants, namely, S233L, E271A and H515P were tracked with DHPLC and the samples showing variations were sequenced. 81 patients (63 females) aged between 12–63 years (45 had juvenile myoclonic epilepsy, 11 childhood absence epilepsy, 14 juvenile absence epilepsy, 7 late onset idiopathic generalized epilepsy, 1 unclassified idiopathic generalized epilepsy, and 3 patients with idiopathic photosensitive occipital lobe epilepsy) were included in this study. We found only one heterozygous S233L variant in a 23-year-old man who has photosensitive form of juvenile absence epilepsy and pattern sensitivity to striped carpets. Other two variants were not found in any of the other patients and controls. Our results suggest that three screened NEDD4-2 variants do not play a leading role in the pathogenesis of photosensitive epilepsy in the Turkish population.

The purpose was to document 4 patients with different epilepsy syndromes, showing electrical status epilepticus during sleep (ESES), without marked cognitive and behavioral regression in the long-term follow-up. The mean age at onset of seizures was 8 years. Absences, myoclonic, focal motor, or generalized tonic - clonic seizures and drop attacks were the prominent seizure types. The neurological examination and neuroimaging findings revealed no abnormality. Focal epileptiform electroencephalographic (EEG) activity was seen in 3 cases, whereas generalized photosensitive epileptic discharges were detected in 1 patient with juvenile myoclonic epilepsy. Neuropsychological evaluations of all cases were within the normal range, and deterioration in mental status was not observed during their mean follow-up duration of 14 years. Our data support the view that ESES can emerge along with different types of childhood epilepsy syndromes, including idiopathic generalized epilepsies, and may not always be a poor prognostic factor.

We present the characteristics of eating epilepsy (EE), which is an underrecognized and complex form of reflex epilepsy. The files of 8996 patients with epilepsy were investigated retrospectively and only 6 cases (0.067%) were found.  Four males and 2 females, aged 20 to 63 years, had focal seizures, mostly with dyscognitive and experiential aura triggered by eating, as well as spontaneous seizures. All had an initial precipitating event for seizures (such as head/birth trauma or encephalitis). In 4 patients, the seizures were induced in the middle of the meal or even closely after the end. In the remaining 2 cases the seizures were at the beginning of the meal, suggesting 2 different mechanisms. Two patients had normal magnetic resonance imaging (MRI), whereas the others had heterogeneous findings. The interictal electroencephalographs (EEGs) showed frequent spikes over a large area on the left temporal region in 5 and over the right temporal area in 1 case. We recorded eating-related seizures originating from the left temporal region in 3 cases. Positron-emission tomography (PET) investigations were concordant with the EEG foci in 2 patients. All but 1 had a therapy-resistant course. Our study suggested that EE is extremely rare and occurred many years after an initial precipitating event for seizures. These focal seizures, starting mostly with experiential/dyscognitive aura, usually originated from the left temporal region, had mostly a therapy-resistant course, and were triggered by different mechanisms during eating with a long latency in most of the cases.

We report a patient with adolescent‐onset, Rasmussen's encephalitis, presenting with intractable focal seizures, mild hemiparesis, cognitive impairment, dystonia, and severe hemiballism. His father had Behcet's disease, considered to be an autoimmune disorder. Recent reports have directly implicated the role of cytotoxic T lymphocytes in the pathogenesis of both Rasmussen's encephalitis and Behcet's disease. The occurrence of Behcet's disease and Rasmussen's encephalitis in the same family suggests involvement of common genetic factors such as HLA haplotypes in both autoimmune disorders. It is possible that members of this family are genetically susceptible to developing autoimmune conditions that have been precipitated by separate environmental triggers.

Some conventional and quantitative EMG studies have already demonstrated a subclinical lower motor neuron involvement in juvenile myoclonic epilepsy (JME). Our aim was to investigate this subclinical involvement by using motor unit number estimation (MUNE) analysis with modified McComas' technique.We enrolled 75 consecutive JME patients and 26 normal controls. All subjects underwent motor and sensory nerve conduction studies, concentric needle EMG and MUNE analysis of the M. abductor pollicis brevis (APB) and M. tibialis anterior (TA). The clinical and EEG findings were evaluated to correlate with MUNE values.MUNE values of the APB (54±25) and TA (35±17) muscles were significantly lower in the JME group (p<0.001) when compared to the normal controls (109±24 and 80±26 for APB and TA muscles, respectively). Our findings show that anterior horn cells were subclinically affected in some JME patients, suggesting a shared background for both JME phenotype and grey matter disorganization in spinal cord.

Three patients with neurosyphilis are reported. The first and third patients presented with convulsive status epilepticus and the second with non‐convulsive status after penicillin administration. In all cerebrospinal fluid and the serum Venereal Disease Research Laboratory Test (VDRL) and Treponema Pallidumhemagglutination (TPHA) or fluorescent treponemal antibody absorption test (FTA‐ABS) were positive, but HIV serology was negative. Their EEGs showed periodic, lateralized, epileptiform discharges (PLEDs) just after SE. The first and third patients had no history of epilepsy. Seizures started as focal motor attacks but then secondarily generalized. The first patient's cranial MRI showed cerebral atrophy and hyperintensity involving bilateral medial and anterior temporal regions, more prominent on the left and which disappeared after penicillin treatment. The second case, after receiving penicillin, had nonconvulsive SE, a clinical presentation suggesting a Jarisch‐Herxheimer reaction (JHR). Her cranial MR revealed moderate cortical atrophy and widespread confluent hyperintense foci mainly in both periventricular areas, corona radiata and centrum semiovale. MRI of the third case showed a large, left sylvian, arachnoid cyst without mass effect. Executive dysfunction was observed in follow‐up neuropsychological tests in all patients. When investigating status epilepticus, neurosyphilis as a cause must not be forgotten.