Extrait

Background and study aims Epilepsy is a condition that affects the brain, which causes a person to experience seizures. It is estimated 1% of the population suffer from epilepsy and between 30-40% of these patients are unable to control their seizures despite trying two or more anti-epileptic drugs (drug refractory focal epilepsy). Surgical treatment can offer a potential cure for these patients. In order to find out if a patient is suitable to undergo surgery, they need to undergo a specialist evaluation to find the part of the brain that is causing the problem. In almost half of patients, performing non-invasive procedures such as brain scans are not enough to find the route of the problem, and so it is necessary to place electrodes (electrical conductors used to measure electrical activity) directly onto the exposed surface of the brain (Stereotactic EEG (SEEG) or depth electrodes). SEEGs carry a number of risks, including bleeding, infection and damage to important brain structures if they are misplaced. The accurate placing of depth electrodes is therefore very important. The iSYS1 trajectory guidance system is a small robotic device that has been developed to improve the accuracy of depth electrode placement. The aim of this study is to investigate the use of the iSYS1 trajectory guidance system compared to the standard technique. Who can participate? Adults with drug refractory focal epilepsy who require a SEEG as part of routine clinical care What does the study involve? Participants who are having a SEEG as part of their normal care are randomly allocated to one of two groups. Those in the first group have the depth electrodes placed using the usual mechanical arm technique. This involves the use of a neuro-navigation system and the surgeon aligning a mechanical arm along a pre-planned trajectory (route). Once the trajectory has been lined up, a cut is made in the skin and a small hole is drilled through the skull. A metal bolt is then screwed into the skull through which the electrode is inserted along a premeasured length to reach the target in the brain. The electrode is then secured in place by the bolt. Those in the second group have the depth electrodes placed using the iSYS1 trajectory guidance system. This involves the use of a neuro-navigation system relaying the plan information to a small guidance system that the surgeon places a few centimetres from the surface of the scalp. The guidance system, through a series of small steps then aligns to the pre-planned trajectory with a high level of accuracy. Once the trajectory has been lined up, a cut is made in the skin and a small hole is drilled through the skull. A metal bolt is then screwed into the skull through which the electrode is inserted along a premeasured length to reach the target in the brain. The electrode is then secured in place by the bolt. The time taken for the electrodes to be placed in both groups is measured during the surgery. 48 hours after surgery, participants then undergo a brain scan to see how accurately the electrodes have been placed and check for any complications such as bleeding. What are the possible benefits and risks of participating? There are no direct benefits or risks involved with participating. Where is the study run from? National Hospital for Neurology and Neurosurgery (UK) When is the study starting and how long is it expected to run for? January 2015 to January 2018 Who is funding the study? Wellcome Trust (Grant number: WT106882) (UK) Who is the main contact? Professor John Duncan [email protected]

Critère d'inclusion

• Drug resistant focal epilepsy

Liens

• isrctn