NCT03094312: ISD SEEG

Evaluation of the Risk of Cognitive Deficit After Surgery of Epilepsy by Dynamic Spectral Imaging (ISD) of the Cognitive Functions in Patients Explored in StereoElectroEncephaloGraphy (SEEG)

Recruiting now NA Last updated 21 January 2026

What this trial tests

NA trial testing Dynamic Spectral Imaging (ISD) in Epilepsy in 50 participants. Currently enrolling.

Timeline

23 June 2017

Primary endpoint
23 January 2030

23 January 2030

Quick facts

Lead sponsor	Hospices Civils de Lyon
Phase	NA
Status	Recruiting now
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	diagnostic
Enrollment	50
Start date	23 June 2017
Primary completion	23 January 2030
Estimated completion	23 January 2030
Sites	1 location across France

Drugs / interventions tested

• Dynamic Spectral Imaging (ISD)

Conditions studied

• Epilepsy — all drugs for Epilepsy →

Sponsor

Hospices Civils de Lyon — full company profile →

Who can join

Adults 18 to 65, any sex, with Epilepsy. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Epilepsy affects between 0.5 and 0.7% of the European population. Despite the availability of numerous drug treatments, one third of patients still have seizures, which are associated with significant cognitive and social complications and excess mortality. In these patients, surgical treatment to remove the epileptogenic zone (EZ), the region of the brain responsible for seizures, is the only approach that can allow control of the disease. However, before investigating this surgery, investigations have to answer two questions: (i) what is the location and extension of the EZ and (ii) what functional risks, both motor and cognitive, would represent the resection of this Cortical region? As it is a functional surgery, it is in fact inconceivable that the surgery will result in an over-handicap. For these reasons, all candidates for surgery benefit from a complete assessment including imaging examinations, a neuropsychological assessment and a long-term video-EEG recording to record seizures. Nevertheless, in some patients, this assessment does not give us a formal answer. In these subjects, it is then necessary to carry out a second step, consisting of an invasive exploration by implantation of intracerebral electrodes during a stereoencephalography (SEEG). Due to its temporal and spatial resolution, the SEEG allows, besides the precise determination of the EZ, to carry out a functional mapping of the cortical regions likely to be included in cortectomy. Conventionally, this mapping is carried out on the basis of the cortical electrical stimulations applied to the implanted electrodes. If this approach is very robust for exploring primary functions such as motor skills or language, it cannot be used to evaluate more complex cognitive tasks such as face recognition or attention Effective cognitive treatment on a daily basis. This has led to the development in recent years, in Lyon and Grenoble, of a complementary approach to cerebral stimulation: dynamic spectral imaging (ISD). Numerous experimental paradigms have demonstrated that the realization of a cognitive task associates with the generation within the cortical regions involved in its treatment of a particular cortical activity. This activity is characterized by oscillations of the cortical rhythm in high frequencies (\> 30 Hz), called gamma activities. The ISD thus consists in mapping this gamma activity during various cognitive tasks, thus making it possible to study more widely the complexity of the cognitive functions. Correlations between gamma activity and cognitive tasks have so far been exclusively performed in the non-epileptic cortex explored at the periphery of the EA during SEEG. Nevertheless, the cortical oscillatory pattern study associated with a specific cognitive task within the EZ could better anticipate complex cognitive deficits that could be generated by the resection of a cortical region.

The main objective of this project is to establish the predictive character of the gamma cortical oscillatory pattern associated with a specific cognitive task on the risk of occurrence of a cognitive disorder after surgery of epilepsy.

Publications & conference data

No peer-reviewed publications indexed yet for this trial.