scholarly journals Noise-Assisted MEMD-Based Phase-Connectivity Analysis to Personalize Closed-Loop DBS Therapy in Epilepsy Patients

2019 ◽  
Author(s):  
Sina Farahmand ◽  
Tiwalade Sobayo ◽  
David J. Mogul

AbstractDeep brain stimulation (DBS) is a treatment that has been explored for controlling seizures in patients with intractable epilepsy. Many clinical and pre-clinical studies using DBS therapy determine stimulation parameters through trial and error. The same stimulation parameters are often applied to the whole cohort, which consequently produces mixed results of responders and non-responders. In this paper, an adaptive non-linear analytical methodology is proposed to extract stimulation frequency and location(s) from endogenous brain dynamics of epilepsy patients, using phase-synchrony and phase-connectivity analysis, as seizures evolve. The proposed analytical method was applied to seizures recorded using depth electrodes implanted in hippocampus and amygdala in three patients. A reduction in phase-synchrony was observed in all patients around seizure onset. However, phase-synchrony started to gradually increase from mid-ictal and achieved its maximum level at seizure termination. This result suggests that hyper-synchronization of the epileptic network may be a crucial mechanism by which the brain naturally terminates seizure. Stimulation frequency and locations that matched the network phase-synchrony at seizure termination were extracted using phase-connectivity analysis. One patient with temporal lobe epilepsy (TLE) had a stimulation frequency ∼15 Hz with the stimulation locations confined to the hippocampus. The other two patients with extra-temporal lobe epilepsy (ETE) had stimulation frequency ∼90 Hz with at least one stimulation location outside of hippocampus. These results suggest that DBS parameters should vary based on the patient’s underlying pathology. The proposed methodology provides an algorithm for tuning DBS parameters for individual patients in an effort to increase the clinical efficacy of the therapy.


2002 ◽  
Vol 16 (1) ◽  
pp. 95-99 ◽  
Author(s):  
Paul S. Buckmaster ◽  
Mary O. Smith ◽  
Christine L. Buckmaster ◽  
Richard A. LeCouteur ◽  
F. Edward Dudek


2019 ◽  
Vol 16 (2) ◽  
pp. 106-109
Author(s):  
Forhad Hossain Chowdhury ◽  
Mohammod Raziul Haque ◽  
AFM Momtazul Haque

Patient presenting as a case of Temporal Lobe Epilepsy (TLE) are usually resistant to antiepileptic drugs and surgery is the treatment of choice. This type of epilepsy may be due to Mesial Temporal Sclerosis (MTS), tumors [i.e. low grade glioma, Arterio-venous Malformation (AVM) etc], trauma, infection (Tuberculosis) etc. Here we report a case of surgically treated TLE that was due to a large tuberculoma in medial temporal lobe. Intractable epilepsy caused by tuberculoma is rare. The only presenting symptoms was Complex partial seizure (Psychomotor epilepsy) for which the patient underwent scalp EEG (Electro Encephalography) and MRI (Magnetic resonance imaging) of brain. The patient was managed by amygdalohippocampectomy with lesionectomy plus standard anterior lobectomy. Postoperatively she was on anti-tubercular therapy and on carbamazepine. The case was seizure and disease free till last follow up. Journal of Surgical Sciences (2012) Vol. 16 (2) : 106-109



2010 ◽  
Vol 112 (6) ◽  
pp. 1301-1307 ◽  
Author(s):  
Chandan G. Reddy ◽  
Nader S. Dahdaleh ◽  
Gregory Albert ◽  
Fangxiang Chen ◽  
Daniel Hansen ◽  
...  

A wide range of devices is used to obtain intracranial electrocorticography recordings in patients with medically refractory epilepsy, including subdural strip and grid electrodes and depth electrodes. Penetrating depth electrodes are required to access some brain regions, and 1 target site that presents a particular technical challenge is the first transverse temporal gyrus, or Heschl gyrus (HG). The HG is located within the supratemporal plane and has an oblique orientation relative to the sagittal and coronal planes. Large and small branches of the middle cerebral artery abut the pial surface of the HG and must be avoided when planning the electrode trajectory. Auditory cortex is located within the HG, and there are functional connections between this dorsal temporal lobe region and medial sites commonly implicated in the pathophysiology of temporal lobe epilepsy. At some surgical centers, depth electrodes are routinely placed within the supratemporal plane, and the HG, in patients who require intracranial electrocorticography monitoring for presumed temporal lobe epilepsy. Information from these recordings is reported to facilitate the identification of seizure patterns in patients with or without auditory auras. To date, only one implantation method has been reported to be safe and effective for placing HG electrodes in a large series of patients undergoing epilepsy surgery. This well-established approach involves inserting the electrodes from a lateral trajectory while using stereoscopic stereotactic angiography to avoid vascular injury. In this report, the authors describe an alternative method for implantation. They use frameless stereotaxy and an oblique insertion trajectory that does not require angiography and allows for the simultaneous placement of subdural grid arrays. Results in 19 patients demonstrate the safety and efficacy of the method.



2013 ◽  
Vol 5 (3) ◽  
pp. 17 ◽  
Author(s):  
Nihal Olgac Dundar ◽  
Berrin Aktekin ◽  
Nilufer Cicek Ekinci ◽  
Duygu Sahinturk ◽  
Ugur Yavuzer ◽  
...  

Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) is a common medically intractable epilepsy syndrome. Although pathogenesis of HS still remains highly controversial, genetics may play a role as a predisposing factor. Previous evidence in a Japanese population revealed that the homozygotes for allele T at position −511 of the interleukin (IL)-1β gene promoter region (IL-1β-511 T/T) confers susceptibility to the development of HS. However, whether this polymorphism has an effect on IL-1β levels in MTLE-HS patients was not demonstrated. This study aimed to analyze the distribution of this particular polymorphism in a group of Turkish HS patients and correlate the polymorphism with IL-1β secretion from the lymphocytes, thus revealing a functional role for IL-1β in the etiopathogenesis of HS. A single base pair polymorphism at position −511 in the promoter region of the IL-1β gene was analyzed. The spontaneous and 1 ng/mL lipopolysaccharide-stimulated production of IL-1β by peripheral blood mononuclear cells after 4 and 24 h of incubation were measured by ELISA method. The heterozygous type (−511 C/T) was the most common genotype. There was no difference in frequency of allele −511 T between patients and controls. Analysis of IL-1β levels, genotype and allele distributions showed no significant difference among the groups (P>0.05). Nevertheless, it was seen that patients who carry a T allele at position -511 of the IL-1β gene had increased IL-1β levels. T-allele carriage may be important. Only IL-1β secretion from the lymphocytes has been assessed in this study. Considering the importance of IL-1β in the etiopathogenesis of HS, further studies are needed to evaluate locally produced IL-1β levels.



Epilepsia ◽  
1996 ◽  
Vol 37 (5) ◽  
pp. 455-458 ◽  
Author(s):  
Susan S. Spencer ◽  
Dennis D. Spencer


2008 ◽  
Vol 62 (suppl_5) ◽  
pp. ONS471-ONS480 ◽  
Author(s):  
Afif Afif ◽  
Stephan Chabardes ◽  
Lorella Minotti ◽  
Philippe Kahane ◽  
Dominique Hoffmann

Abstract Objective: This study investigates the feasibility, safety, and usefulness of depth electrodes stereotactically implanted within the insular cortex. Methods: Thirty patients with suspected insular involvement during epileptic seizure underwent presurgical stereotactic electroencephalographic recordings using 10 to 16 depth electrodes per patient. Among these, one or two electrodes were implanted via an oblique approach to widely sample the insular cortex. Results: Thirty-five insular electrodes were implanted in the 30 patients without morbidity. A total of 226 recording contacts (mean, 7.5 contacts/patient) explored the insular cortex. Stereotactic electroencephalographic recordings of seizures allowed the differentiation into groups: Group 1, 10 patients with no insular involvement; Group 2, 15 patients with secondary insular involvement; and Group 3, five patients with an initial insular involvement. In temporal epilepsy (n = 17), the insula was never involved at the seizure onset but was frequently involved during the seizures (11 out of 17). In fron-totemporal or frontal epilepsy, the insula was involved at the onset of seizure in five out of 13 patients. All patients in Groups 1 and 2 underwent surgery, with a seizure-free outcome in 76.2% of patients. In Group 3, only two of the five patients underwent surgery, with a poor outcome. In temporal lobe epilepsy, surgical outcome tended to be better in Group 1 compared with Group 2 in this small series: results were good in 83.3% (Engel I) versus 72.7%. Conclusion: Insula can be safely explored with oblique electrodes. In temporal lobe epilepsy, insular involvement does not significantly modify the short-term postoperative outcome. Future larger studies are necessary to clarify the long-term prognostic value of insular spread.



1987 ◽  
Vol 66 (4) ◽  
pp. 489-499 ◽  
Author(s):  
George A. Ojemann

✓ There has been a recent renewal of interest in surgical therapy for medically intractable epilepsies. Cortical resection and callosotomy are the most widely accepted modes of surgical management. The indications for each of these approaches are reviewed. Although there has been much interest in imaging techniques, including positron emission tomography, to identify epileptogenic zones, identification still depends primarily on the electroencephalogram (EEG). There are several approaches to the evaluation and intraoperative management of patients undergoing cortical resection for temporal lobe epileptogenic zones. These range from selection based on scalp interictal EEG criteria, with resections guided by electrocorticography and functional mapping, to selection based on the location of ictal onset as recorded by chronically implanted depth electrodes, with an anatomically standard resection of the temporal lobe or resection limited to amygdalohippocampectomy. No one approach provides the optimum balance of benefits to risks and costs for all patients. The relative value of the different approaches for various populations of patients with medically intractable partial complex seizures is reviewed. Techniques for minimizing the morbidity of these operations, especially in regard to language and memory, are also discussed, as are the contributions to an understanding of the neurobiology of human epilepsy and human higher functions derived from the surgical therapy of epilepsy.



Epilepsia ◽  
2002 ◽  
Vol 43 (10) ◽  
pp. 1197-1209 ◽  
Author(s):  
Maxime Guye ◽  
Yann Le Fur ◽  
Sylviane Confort-Gouny ◽  
Jean-Philippe Ranjeva ◽  
Fabrice Bartolomei ◽  
...  


Neurology ◽  
1981 ◽  
Vol 31 (10) ◽  
pp. 1352-1352 ◽  
Author(s):  
J. Montplaisir ◽  
M. Laverdiere ◽  
J. M. Saint-Hilaire ◽  
J. Walsh ◽  
G. Bouvier


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