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Introduction: Deep brain stimulation of the anterior nucleus of thalamus (ANT-DBS) is an approved procedure for drug-resistant epilepsy. However, the preferred location inside ANT is not well known. In this study, we investigated the relationship between stereotactical coordinates of stimulated contacts and clinical improvement, in order to define the ideal target for ANT-DBS. Methods: Individual contact's coordinates were obtained in the Montreal Neurological Institute (MNI) 152 space, with the utilization of advanced normalization tools and co-registration of pre- and postoperative MRI and CT images in open-source toolbox lead-DBS with the "Atlas of the Human Thalamus." Each contact's pair was either classified as a responder (≥50% seizure reduction and absence of intolerable adverse effects) or nonresponder, with a minimum follow-up of 11 continuous months of stimulation. Results: A total of 19 contacts' pairs were tested in 14 patients. The responder rate was 9 out of 14 patients (64.3%). In 4 patients, a change in contacts' pairs was needed to achieve this result. A highly encouraging location inside ANT (HELIA) was delimited in MNI space, corresponding to an area in the anterior and inferior portion of the anteroventral (AV) nucleus, medially to the endpoint of the mammillothalamic tract (ANT-mtt junction) (x [3.8; 5.85], y [−2.1; −6.35] and z [6.2; 10.1] in MNI space). Statistically significant difference was observed between responders and nonresponders, in terms of the number of coordinates inside this volume. Seven responders and two nonresponders had at least 5 of 6 coordinates (2 electrodes) inside HELIA (77.8% sensitivity and 80% specificity). In 3 patients, changing to contacts that were better placed inside HELIA changed the status from nonresponder to responder. Conclusions: A relationship between stimulated contacts' coordinates and responder status was observed in drug-resistant epilepsy. The possibility to target different locations inside HELIA may help surpass anatomical variations and eventually obtain increased clinical benefit. [ABSTRACT FROM AUTHOR]

Mesial temporal lobe seizures can be misdiagnosed as panic attacks. There is a spectrum of symptoms that are common to both, like fear sensation. We report a case of a young woman, initially diagnosed as having panic attacks of short duration. The symptoms persisted for two years despite treatment with SSRIs. Epileptic seizures were suggested when the patient started reporting involuntary limb movements during some of the episodes. Further investigations showed mesial temporal sclerosis on MRI and epileptic activity in EEG, and she began antiepileptic treatment. In some patients with panic attacks, particularly if associated with atypical features, the possibility of epilepsy should be considered. [ABSTRACT FROM AUTHOR]

Sleep-related eating disorder (SRED) is characterised by eating episodes during the first period of the night sleep with partial loss consciousness, and amnesia. It can rarely be induced by some drugs, including zolpidem. We present a video report of a patient with a 1-year history of SRED caused by zolpidem causing important repercussions in the sleep structure and life quality. The night eating episodes ceased promptly with discontinuation of zolpidem. Upon the follow-up, the sleep structure improved and the daily consequences disappeared. As in few reported cases of zolpidem-induced SRED, our patient was suffering from the parasomnia for a long time before the diagnosis. Active exclusion of symptoms suggestive of SRED in patients under zolpidem treatment can avoid the deleterious effect of the sleep disorder. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fibrillation/sharp-waves (fibs-sw) are considered an essential neurophysiological marker in Amyotrophic Lateral Sclerosis (ALS). We investigated how frequently an initial electrophysiological (EMG) evaluation, performed in ALS patients, revealed no fibs-sw. METHODS: The initial EMG studies from 68 ALS patients were analysed. The presence of fibs-sw in at least two muscles of each limb and two cranial-innervated muscles was assessed. RESULTS: We observed no fibs-sw in cranial-innervated muscles, and 7/15 bulbar-onset patients had no fibs-sw in limb muscles. Two of 28 upper-limb-onset patients, who had a short history before EMG, showed no fibs-sw. All lower-limb-onset patients had fibs-sw. Generally patients with no fibs-sw had diffuse abundant fasciculations. CONCLUSIONS: The absence of fibs-sw should not necessarily preclude the neurophysiological diagnosis of ALS in bulbar-onset patients. Early affected upper-limb-onset patients might show no fibs-sw, but profuse fasciculations associated with mild to moderate denervation–reinnervation in weak muscles are found. (Amyot Lat Scler 1999: 1:29–32). [ABSTRACT FROM AUTHOR]

Introduction and Objectives: The study of complex refractory epilepsies frequently requires data form invasive EEG. The regions of interest can be monitored with depth electrodes. These electrodes are usually implanted with stereotactic frames or robotized systems that are not readily available in many centres with a smaller surgery volume. Over the last years, neuronavigation has proven to be a valuable tool capable of replacing classic stereotactic frames in less precision demanding surgeries. In this work we analyse the precision of non-frame based system for the implantation of stereo-EEG (SEEG) electrodes in our centre. Material and Methods: The retrospective analysis included all patients with medically refractory focal epilepsy who underwent implantation of depth electrodes for extraoperative EEG monitoring between June 2012 and January 2016. Trajectory planning was done with either Cranial? 4 or Synergy Cranial? 2.2 from Medtronic® and implantation of Dixi® or Alcis® electrodes was done with Mayfield® head clamp and Vertek® II articulated arm. All patients underwent early post-operative image control of implantation that was fused with pre-operative imaging. Analysis of demographics included entry-point and target accuracy, depth of each trajectory, procedure-related complications and quality of EEG recording. Results: Fifty-one SEEG electrodes were implanted in 6 patients. Their mean age was 27.5 years (8-49 years old). On average, 8.25 electrodes were implanted per patient. The average time of implantation planning was 45 minutes. The average operative time was 141 minutes (range 104-178 minutes) with an average of 17 minutes per electrode (range 14.86-19.17 minutes). Measured accuracy obtained from entry point in 4 patients (35 electrodes) and target in 5 patients (45 electrodes) demonstrated a median entry point error of 2.41 mm and a median target point error of 2.51 mm. Planned target regions were reached in all 51 trajectories and there weren't any procedure-related complications. Seizures were detected in more than one electrode in all 6 patients and a strategy was possible to delineate with data obtained from this SEEG. Discussion and Conclusions: This technique of implantation of SEEG depth electrodes has the necessary accuracy to achieve the goals of this type of EEG monitoring. In spite of having a lower accuracy compared to the classic systems, knowing the error margin allows us to establish security boundaries in order to avoid vascular structures. The simpler workflow of the neuronavigated implantation of depth electrodes can make this kind of investigation readily available in more epilepsy centres, improving their ability to treat even more complex cases. [ABSTRACT FROM AUTHOR]

Introduction: Patients with a neuronal migration disordered characterized by subcortical band heterotopia are prone to develop refractory epilepsy. Some attempts have been made to treat this condition surgically with Stereo-EEG and focal resections with discouraging results. In our series of deep brain stimulation of anterior nuclei of the thalamus (DBS-ANT), from 12 patients, 2 were due to this development disorder. Case Study: Seizure outcome was reviewed now at 12 and 18 months en patient 1 and 2. Both patients showed a greater than 50% decrease in seizure frequency and an increase in seizure free time. After surgery they both had a transient depressive syndrome that responded to anti-depressive medication. Discussion: Deep brain stimulation of ANT has shown a good seizure outcome in these two cases. We propose that this procedure could be considered in the treatment of patients with subcortical band heterotopia with refractory epilepsy. The etiology of depression is probably multifactorial but might be a transient adverse event of DBS-ANT. [ABSTRACT FROM AUTHOR]

Introduction: Deep Brain Stimulation (DBS) of the Anterior Nuclei of Thalami (ANT) has a growing interest as a palliative surgery for refractory epilepsy. The bilateral ANT-DBS may have a place in focal epilepsies when no focal resection is indicated or when patients refuse resective surgery. Material and Methods: The Epilepsy Surgery Group of the Hospital de Santa Maria (CHLN) started this approach in January 2011, and we have operated 12 patients (7 females) so far. Median time of epilepsy before implantation was 26 years (7-46) and median number of seizures per month 15 seizures/month (3-39). All patients have already tried 3 or more antiepileptic drugs. Three patients had previous epilepsy surgeries, one a VNS and other two resective surgeries. Electrodes were implanted with Leksell® stereotactic frame with targets and trajectories obtained from FrameLink® Medtronic's software. Both 3387 and 3389 electrodes were used through a trans-ventricular cannulated approach in the majority of the patients (9/12). Post-operative control of electrode contacts was done with CT fused with pre-operative MRI and compared to published stereotactic atlases. Results: All 12 patients have at least one contact in one ANT and 11 in both anterior nuclei. Two patients required additional surgeries due to slippage of electrode(s) to the III ventricle during a trans-ventricular approach. No intraventricular bleeding was seen in post-operative CT of all patients and no major complications related to surgery were recorded. Seizure frequency reduction was seen in more than half of the patients but almost all reported a decrease in severity of their seizures. Approximately one third of the patients developed a newly or aggravated depression early after stimulation initiation that required medication. No suicidal ideation was found in any of them. Discussion and Conclusions: The ideal candidates for ANT-DBS is yet to be found but the low incidence of major complications from this surgery and the reversibility of those related to stimulation makes this neuromodulation technique an option to treat otherwise difficult refractory epilepsy cases. Multicenter studies allow us to collect more cases faster but single center series with their more standardized approach may also add some important information. [ABSTRACT FROM AUTHOR]