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Objective: Short‐term outcomes of deep brain stimulation of the anterior nucleus of the thalamus (ANT‐DBS) were reported for people with drug‐resistant focal epilepsy (PwE). Because long‐term data are still scarce, the Medtronic Registry for Epilepsy (MORE) evaluated clinical routine application of ANT‐DBS. Methods: In this multicenter registry, PwE with ANT‐DBS were followed up for safety, efficacy, and battery longevity. Follow‐up ended after 5 years or upon study closure. Clinical characteristics and stimulation settings were compared between PwE with no benefit, improvers, and responders, that is, PwE with average monthly seizure frequency reduction rates of ≥50%. Results: Of 170 eligible PwE, 104, 62, and 49 completed the 3‐, 4‐, and 5‐year follow‐up, respectively. Most discontinuations (68%) were due to planned study closure as follow‐up beyond 2 years was optional. The 5‐year follow‐up cohort had a median seizure frequency reduction from 16 per month at baseline to 7.9 per month at 5‐year follow‐up (p <.001), with most‐pronounced effects on focal‐to‐bilateral tonic–clonic seizures (n = 15, 77% reduction, p =.008). At last follow‐up (median 3.5 years), 41% (69/170) of PwE were responders. Unifocal epilepsy (p =.035) and a negative history of epilepsy surgery (p =.002) were associated with larger average monthly seizure frequency reductions. Stimulation settings did not differ between response groups. In 179 implanted PwE, DBS‐related adverse events (AEs, n = 225) and serious AEs (n = 75) included deterioration in epilepsy or seizure frequency/severity/type (33; 14 serious), memory/cognitive impairment (29; 3 serious), and depression (13; 4 serious). Five deaths occurred (none were ANT‐DBS related). Most AEs (76.3%) manifested within the first 2 years after implantation. Activa PC depletion (n = 37) occurred on average after 45 months. Significance: MORE provides further evidence for the long‐term application of ANT‐DBS in clinical routine practice. Although clinical benefits increased over time, side effects occurred mainly during the first 2 years. Identified outcome modifiers can help inform PwE selection and management. [ABSTRACT FROM AUTHOR]

Background: Cerebrovascular disease (CVD) is a major contributor to epilepsy; however, patients with epilepsy also have a significantly increased risk of stroke. The way in which epilepsy contributes to the increased risk of stroke is still uncertain and is ill‐characterized in neuropathological studies. A neuropathological characterization of cerebral small vessel disease (cSVD) in patients with chronic epilepsy was performed. Methods: Thirty‐three patients with refractory epilepsy and hippocampal sclerosis (HS) submitted to epilepsy surgery from a reference center were selected between 2010 and 2020 and compared with 19 autopsy controls. Five randomly selected arterioles from each patient were analyzed using a previously validated scale for cSVD. The presence of CVD disease imaging markers in pre‐surgical brain magnetic resonance imaging (MRI) was studied. Results: There were no differences in age (43.8 vs. 41.6 years; p = 0.547) or gender distribution (female gender 60.6% vs. male gender 52.6%; p = 0.575) between groups. Most CVD findings in brain MRI were mild. Patients had a mean time between the epilepsy onset and surgery of 26 ± 14.7 years and were medicated with a median number of three antiseizure medication (ASMs) [IQR 2–3]. Patients had higher median scores in arteriolosclerosis (3 vs. 1; p < 0.0001), microhemorrhages (4 vs. 1; p < 0.0001) and total score value (12 vs. 8.9; p = 0.031) in comparison with controls. No correlation was found between age, number of years until surgery, number of ASMs or cumulative defined daily dosage of ASM. Conclusion: The present study provides evidence supporting the increased burden of cSVD in the neuropathological samples of patients with chronic epilepsy. [ABSTRACT FROM AUTHOR]

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]

The occurrence of seizures in specific types of epilepsies can follow a 24-hour nonuniform or nonrandom pattern. We described the 24-hour pattern of clinical seizures in patients with focal refractory epilepsy who underwent video-electroencephalography monitoring. Only patients who were candidates for epilepsy surgery with an unequivocal seizure focus were included in the study. A total of 544 seizures from 123 consecutive patients were analyzed. Specific time of seizures were distributed along 3- or 4-hour time blocks or bins throughout the 24-hour period. The mean age of the subjects was 37.7 years, with standard deviation of 11.5 years, median of 37. The majority were females (70/56%). The majority of patients had a seizure focus located in the mesial temporal lobe (102/83%) and in the neocortical temporal lobe (13/11%). The remaining patients had a seizure focus located in the extratemporal lobe (8/6%). The most common etiology was mesial temporal sclerosis (86/69.9%). Nonuniform seizure distribution was observed in seizures arising from the temporal lobe (mesial temporal lobe and neocortical temporal lobe), with two peaks found in both 3- and 4-hour bins: 10:00–13:00/16:00–19:00 and 08:00–12:00/16:00–20:00 respectively (p = 0.004). No specific 24-hour pattern was identified in seizures from extratemporal location. The 24-hour rhythmicity of seizure distribution is recognized in certain types of epilepsy, but studies on the topic are scarce. Their replication and validation is therefore needed. Our study confirms the bimodal pattern of temporal lobe epilepsy independently of the nature of the lesion. However, peak times differ between different studies, suggesting that the ambient, rhythmic exogenous factors or environmental/social zeitgebers, may modulate the 24-hour rhythmicity of seizures. Characterization of these 24-hour patterns of seizure occurrence can influence diagnosis and treatment in selected types of epilepsy, such as the case of temporal lobe epilepsy, the most common drug-resistant epilepsy. [ABSTRACT FROM AUTHOR]

Summary: Surgery is the treatment of choice for refractory temporal lobe epilepsies, but unexpected seizure recurrences occur and the AEDs management strategy may be an implicated factor. We evaluated the AEDs management''s role in the outcome of post surgical epilepsy patients with hippocampal sclerosis (HS). Epileptic patients submitted to amigdalohippocampectomy due to HS in Engel class IA 12months after surgery were selected. The following variables were studied: age, gender, time of post-surgical follow-up, present Engel class, number of antiepileptic AEDs before surgery and at the time of the interview, AED changes after surgery (stopped, increased, decreased, maintained), timing for AED changes after surgery and seizure recurrences. Sixty-seven consecutive patients were studied (mean time of follow-up of 4.9±2.8 years). Among these, 46.3% were tapering AEDs, 38.8% had not changed and 14.9% had increased AEDs. The global recurrence rate was 32.8%. Recurrence rates for patients tapering and not tapering AEDs were similar (34.2% and 31%, respectively). Fifteen patients tapered AEDs before 2 years and 20 at or 2 years after surgery, with similar recurrence rates (33% and 30%, respectively). All patients who recurred due to AED tapering and 66.7% of the patients who recurred with no AED reduction resumed the Engel class I. This study suggests that in HS patients submitted to AHE who are seizure free during the first postsurgical year, AEDs tapering is achieved in a substantial percentage of patients. Tapering AEDs, independently of its timing, will induce seizure recurrence in about a third of patients. However, patients relapsing after tapering AEDs regain control after resuming therapy. [Copyright &y& Elsevier]