s of Poster Presentations / Clinical Neurophysiology 125, Supplement 1 (2014) S1–S339 S171 variants on the EEG. Recently, some genes or genetic polymorphisms have been associated with brain development and eventually with epilepsies associated with structural brain lesions. Thus, it is plausible that some of these genes might also influence epileptogenicity in patients with epilepsy. Accordingly, genes coding Discoidin Domain Receptor Tyrosine Kinase 2 (DDR2), Tescalcin (TESC), and High Mobility Group A Protein (HMGA2) were associated with brain volume, and might influence epileptogenicity. Objective: Investigate the association between DDR2, TESC and HMGA2 genes and interictal spike activity in temporal lobe epilepsy (TLE). Methods: Case-control study of 76 patients with TLE exploring the influence of polymorphisms rs10494373 of DDR2, rs7294919 of TESC and rs10784502 of HGMA2 on the incidence, distribution and lateralization of interictal epileptiform EEG of these patients. All individuals had an awake and asleep standard EEG recordings, and tracings were analyzed by experienced and certified electroencephalographers. Results: No association between rs10494373 of DDR2, and rs7294919 of TESC polymorphisms with EEG spike rates was found in TLE, regarding the EEG variables studied. However, presence of C allele in homozygosis in rs10784502 variant of HGMA2 was associated with significant less interictal discharges (p=0.008), in other words, presence of T allele in this specific polymorphism was associated with a doubling of discharges per minute, when compared with C allele in homozygosis (OR: 2.15±2.99 × 1.01±0.65). Conclusion: Our data allow us to hypothesize that variability in the HMGA2 gene might influence EEG interictal epileptiform activity and epileptogenicity in patients with TLE. We believe that further studies will shed some light on molecular mechanisms involved in the generation of EEG epileptiform activity. P459 Electro-clinical features of focal epilepsy patients with postictal generalized EEG suppression K. Jin1, H. Itabashi1, K. Kato1, Y. Kakisaka1, M. Iwasaki2, N. Nakasato1 1Tohoku University Graduate School of Medicine, Epileptology, Sendai, Japan; 2Tohoku University Graduate School of Medicine, Neurosurgery, Sendai, Japan Question: Postictal generalized EEG suppression (PGES) may be associated with sudden unexpected death in patients with epilepsy. Generalized tonic-clonic seizure (GTCS) is one of the well-known risk factors for PGES. However, which types of epilepsy are associated with PGES remain unclear. The present study investigated the electro-clinical features of focal epilepsy patients who suffered secondary GTCSs (sGTCSs) with PGES. Methods: We retrospectively reviewed 32 consecutive patients (13 men) with focal epilepsy aged 13 to 47 years, who presented with sGTCSs during long-term video EEG monitoring. PGES was determined using the previously published criterion of generalized absence of EEG activity of amplitude >10 μV. Patients with at least one sGTCS showing PGES were classified into the PGES (+) group (n=18, 56%). Electro-clinical findings including localization of epileptic foci and lateralizing signs on semiology were compared between the PGES (+) and (−) groups. Results: Temporal lobe epilepsy (TLE) was significantly (p G missense mutation in SCN8A. Electroencephalography (EEG) showed slight low-voltage background activity and occasional interictal epileptiform discharges in bilateral temporal areas during the first months. Ictal EEG was characterized by bilateral centrotemporal theta rhythm. Burst-suppression-like pattern in sleep recording was noticed at 11 months of age. He died at the age of 1 year and 5 months due to progressive respiratory failure during respiratory illness. Conclusion: Mutations in SCN8A can lead to EIEE with a broad spectrum of EEG and clinical features. Detailed phenotypic descriptions are needed to avoid unnecessary investigations and optimize the therapy. P461 Vagus nerve stimulation is beneficial in a patient with postural orthostatic tachycardia syndrome: a case report A. Bujan Kovac1, S. Hajnsek1, Z. Petelin Gadze1, S. Nankovic1, G. Mrak2, V. Sulentic1, I. Kovacevic1, I. Adamec1, M. Habek1 1University Hospital Centre Zagreb, Dept. of Neurology, Zagreb, Croatia; 2University Hospital Centre Zagreb, Dept. of Neurosurgery, Zagreb, Croatia Question: Postural orthostatic tachycardia syndrome (POTS) is defined by a heart rate increment of 30 beats/min or more within 10 minutes of standing or head-up tilt (HUT) in the absence of orthostatic hypotension. Vagal nerve stimulation (VNS) is a safe and effective adjunctive treatment for drug-resistant epilepsy when surgery is inadvisable. Limited data suggest that long-term VNS therapy might affect cardiac autonomic function. However, there are no data of the VNS utility in patients with POTS. Methods: A 29-year-old female patient was implanted with VNS due to pharmacoresistant epilepsy (elementary sensory-motor partial seizures of the left extremities and complex partial seizures of temporal origin with occasional secondary generalization. Couple of years she noticed palpitations and dizziness in standing upright that were relieved by sitting or lying flat. Brain MRI showed bilateral frontoparietal polymicrogyria and right subependimal nodular heterotopia. During the preoperative work-up autonomic nervous system testing revealed POTS that was refractory to life style modification measures. Results: One weak after implantation, VNS was initiated at 0.25 mA (duty cycle set to a 30-Hz signal frequency, a 500-ms pulse width, 30 sec of on-time, and 3 min of off-time). HUT done at one month and three months after implantation was normal. VNS was gradually increased to 1 mA which led to significant reduction in seizure rate and disappearance of orthostatic intolerance symptoms. Conclusion: To our knowledge, this is the first reported case of the positive VNS effect in patient with POTS. Further studies with a larger number of patients are needed. P462 Diffuse brain dysfunction in benign adult familial myoclonus epilepsy (BAFME) T. Hitomi1, K. Kobayashi2, T. Kondo2, R. Matsumoto3, K. Terada4, M. Kanda5, R. Takahashi2, A. Ikeda3 1Kyoto University Graduate School of Medicine, Clinical Laboratory Medicine, Kyoto, Japan; 2Kyoto University Graduate School of medicine, Neurology, Kyoto, Japan; 3Kyoto University Graduate School of Medicine, Epilepsy, Movement Disorders and Physiology, Kyoto, Japan; 4National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders, Epilepsy, Shizouka, Japan; 5Takeda General Hospital, Neurology, Kyotio, Japan Objectives: To clarify the clinical implication of posterior dominant rhythm