Recording "Fast Ripples" Using Microelectrodes During Stereo-encephalography in Patients With Drug-resistant Partial Epilepsy

Epilepsy Clinical Trial

— Epi-FaR  

Official title:

Feasibility and Interest of Recording "Fast Ripples" Using Microelectrodes During Stereo-encephalography in Patients With Drug-resistant Partial Epilepsy

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02491476
• Other study ID #: RC31/13/6899
• Secondary ID: 2014-A00747-40
• Status: Completed
• Phase: N/A
• Start date: March 2015
• Est. completion date: September 18, 2022

Study information

• Verified date: June 2023
• Source: University Hospital, Toulouse
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The main objective of this study is to evaluate the feasibility of recording fast-ripples, a potential new biomarker of epilepsy, using the new micro-macroelectrodes developed by Dixi-Medical.

Description:

Partial epilepsies are refractory to medical treatment in 30% of the cases (Refractory Partial Epilepsy or RPE). Patients with RPE suffer from social and occupational disability, an increased risk associated with seizures (traumatic brain injury, accidents), but also a higher risk of sudden unexplained death (2 to 3 times higher) than the general population. Moreover, the medical and social burden of these patients is heavy, representing a significant cost to society.

In some cases, surgical treatment with resection of the epileptogenic zone (EZ) can be proposed. The presurgical evaluation includes various investigations seeking to clarify the location of the EZ; but this approach is sometimes insufficient and the definition of the EZ then requires invasive exploration through intracerebral EEG recording (stereo-EEG, SEEG). This latter technique is currently the preferred standard to define the EZ. It involves implanting electrodes in the brain areas suspected to belong to the seizure network. 50 to 70% of patients investigated with this technique will have epilepsy surgery.

In recent years, a series of studies in animals and humans have suggested that some oscillations, very short and at very high frequency (> 250 Hz), called "fast ripples" (FRs) could be a good biomarker of the EZ (for a review see Zijlmans et al, 2012). The FRs are more easily recorded from microelectrode (diameter: 20-40 microns).

The purpose of this study is to evaluate a new medical device designed by DixiMedical to record FRs, combining micro and regular clinical electrodes.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 54
• Est. completion date: September 18, 2022
• Est. primary completion date: August 18, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 12 Years to 65 Years

Eligibility

Inclusion Criteria:

• Patient with RPE in whom SEEG is required to precisely localize the seizure focus

Exclusion Criteria:

Patients with SEEG contra-indication:

• severe psychiatric disorders,

• severe agitation during their crisis

• contraindication for performing an MRI: claustrophobia, a cardiac or neural stimulator, ferromagnetic surgical clips, cochlear implants, intraocular metallic foreign body or in the nervous system,

• contraindication to intracerebral investigation (macro-electrodes): ongoing infection, severe associated pathology (cardiac, pulmonary, renal, hepatic), pregnant or nursing women,

• anti thrombotic ongoing treatment.

Related Conditions & MeSH terms

• Epilepsies, Partial
• Epilepsy

Intervention

Device:
• intracerebral micro-macroelectrodes
All patients will be implanted with usually 4 micro-macroelectrodes (replacing the regular clinical macroelectrodes). The primary and secondary outcomes will then be assessed.

Locations

Country	Name	City	State
France	University Hospital Toulouse	Toulouse	Midi-Pyrenees

Sponsors (3)

Lead Sponsor	Collaborator
University Hospital, Toulouse	CerCo, CNRS Cerco UMR5549 CHU Purpan Toulouse France, DIXI Medical, Besançon, France

Country where clinical trial is conducted

France, 

References & Publications (8)

Bragin A, Wilson CL, Staba RJ, Reddick M, Fried I, Engel J Jr. Interictal high-frequency oscillations (80-500 Hz) in the human epileptic brain: entorhinal cortex. Ann Neurol. 2002 Oct;52(4):407-15. doi: 10.1002/ana.10291. — View Citation

Crepon B, Navarro V, Hasboun D, Clemenceau S, Martinerie J, Baulac M, Adam C, Le Van Quyen M. Mapping interictal oscillations greater than 200 Hz recorded with intracranial macroelectrodes in human epilepsy. Brain. 2010 Jan;133(Pt 1):33-45. doi: 10.1093/brain/awp277. Epub 2009 Nov 17. — View Citation

Demont-Guignard S, Benquet P, Gerber U, Biraben A, Martin B, Wendling F. Distinct hyperexcitability mechanisms underlie fast ripples and epileptic spikes. Ann Neurol. 2012 Mar;71(3):342-52. doi: 10.1002/ana.22610. — View Citation

Jacobs J, Levan P, Chatillon CE, Olivier A, Dubeau F, Gotman J. High frequency oscillations in intracranial EEGs mark epileptogenicity rather than lesion type. Brain. 2009 Apr;132(Pt 4):1022-37. doi: 10.1093/brain/awn351. Epub 2009 Mar 18. — View Citation

Jacobs J, Zijlmans M, Zelmann R, Chatillon CE, Hall J, Olivier A, Dubeau F, Gotman J. High-frequency electroencephalographic oscillations correlate with outcome of epilepsy surgery. Ann Neurol. 2010 Feb;67(2):209-20. doi: 10.1002/ana.21847. — View Citation

Staba RJ, Frighetto L, Behnke EJ, Mathern GW, Fields T, Bragin A, Ogren J, Fried I, Wilson CL, Engel J Jr. Increased fast ripple to ripple ratios correlate with reduced hippocampal volumes and neuron loss in temporal lobe epilepsy patients. Epilepsia. 2007 Nov;48(11):2130-8. doi: 10.1111/j.1528-1167.2007.01225.x. Epub 2007 Jul 28. — View Citation

Worrell GA, Gardner AB, Stead SM, Hu S, Goerss S, Cascino GJ, Meyer FB, Marsh R, Litt B. High-frequency oscillations in human temporal lobe: simultaneous microwire and clinical macroelectrode recordings. Brain. 2008 Apr;131(Pt 4):928-37. doi: 10.1093/brain/awn006. Epub 2008 Feb 7. — View Citation

Zijlmans M, Jiruska P, Zelmann R, Leijten FS, Jefferys JG, Gotman J. High-frequency oscillations as a new biomarker in epilepsy. Ann Neurol. 2012 Feb;71(2):169-78. doi: 10.1002/ana.22548. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Evaluation of the feasibility of recording Fast Ripples (FRs)	Proportion of patients who are registered more than 60 FRs per hour the day 3 and the day 4 on the micro-macro electrode in the presumed epileptogenic zone, compared to the number of patients included	During 5 days
Secondary	Evaluation of the interest of FRs	Sum of FRs recorded over the 5 days.	During 5 days
Secondary	Evolution of the hourly frequency of FRs	The evolution of the hourly frequency of FRs recorded by the microelectrodes depending on the day of recording.	During 5 days
Secondary	Effectiveness of microelectrodes and macroelectrodes	Number of FRs stored on the macro-blocks immediately adjacent to the microelectrodes located in the EZ.	During 5 days
Secondary	safety of micro-macroelectrodes	A quantitative and qualitative description of the side effects associated with the procedure.	During 5 days