What is epilepsy ?

Epilepsy is a neurological disorder which affects all populations in the world. It is characterized by recurrent seizures which appear as brief episodes of involuntary shaking affecting part of the body (partial seizures) or the whole body (generalized seizures).
These seizures result from excessive electrical discharges in a group of brain cells and may occur in different parts of the brain. The seizures may vary in intensity, ranging from short losses of attention or shaking muscles to severe prolonged convulsions. Their frequency can also vary from less than once a year to several times a day.

One single seizure is not considered as epilepsy (up to 10% of the world’s population has at least one during a lifetime). The disease is defined by the onset of at least two spontaneous seizures.
Although seizures can be controlled by medication for the large majority of people suffering from epilepsy, 20% of patients are pharmacoresistant. Because of this pharmacoresistance, 30% of partial epileptic patients might be candidates for surgery. Today only 1 patient in 100 is operated on.

50 million people suffer from epilepsy worldwide, making it one of the world’s most common neurological disorders
80% of people suffering from epilepsy live in low- and middle-income countries
70% of Epilepsy cases are treatable
3/4 of people affected by epilepsy in low- and middle-income countries do not benefit from the treatment they need
Epilepsy is a neurological disorder which affects people of all ages. In many areas of the world, people affected by epilepsy and their families may be confronted by stigmatization and discrimination.


The clinical manifestations of seizures vary and depend on the location in the brain of the disturbance and its propagation.
Temporary symptoms may be observed such as :

  • disorientation or loss of awareness,
  • motor or sensory disorders (sight, hearing, taste),
  • mood swings or cognitive function disorders.

Generalized epilepsy :

The most typical manifestation of generalized epilepsy is known as tonic-clonic seizure. It is accompanied by a complete loss of awareness and includes three phases :

  • The tonic phase lasting 1 or 2 minutes. All the muscles suddenly contract, sometimes causing the patient to bite his/her own tongue.
  • The clonic phase lasting around 20 seconds. This is characterized by a series of diffuse, irregular muscle contractions, with respiratory blocking.
  • The postictal phase. This corresponds to complete muscle release. Breathing becomes noisy and heavy (snoring). Incontinence may also occur.

This type of seizure lasts several minutes in all (less than ten minutes) and may lead to a fall or injury. In some cases, generalized seizures appear differently with, for example :

  • movements known as "myoclonic" movements (bilateral symmetrical muscle twitches which the patient can remember) ;
  • atony (absence of muscle tone), causing the person to suddenly go limp and fall to the ground;
  • absences which mainly affect children and last 10 to 20 seconds in general.

During these episodes, the person concerned will suddenly interrupt his/her activity. He or she will have a vacant stare and not respond to questions from those around him/her. After the seizure, the person will progressively regain consciousness without any recollection of what has happened.

Our therapeutic offer

Stereo-electroencephalography (SEEG)

For 20% of pharmacoresistant patients, surgical is one treatment option.

SEEG is a surgical intervention which consists of installing electrodes in the brain, with great precision, directly in contact with the area which is assumed to be responsible for epilepsy.
These electrodes record the brain’s activity and collect quality information in order to locate the areas responsible for the epileptic seizures with the greatest precision.  After the examination, the medical team can decide whether surgery to cure the epilepsy should be envisaged.

SEEG uses both electroencephalogram techniques and stereotaxy (to locate the operatory zone in all three spatial dimensions).This procedure allows the neurosurgeon to implant electrodes under the skull to capture the brain’s electrical activity. The epileptogenic foci can be located as accurately as possible in this way.


Using ROSA® to perform minimally invasive SEEG allows the medical team to understand and identify the epileptogenic foci responsible for the seizures with a non-invasive neurosurgical approach. ROSA® allows the team to map the placement of in-depth electrodes and position them through small drill-holes in the skull along trajectories planned by the surgeon.

ROSA® allows the surgeon and neurologist to plan the surgery on patient images by defining the exact points where the electrodes should be implanted, and to position them safely and accurately with the help of robotic guidance.

Benefits and risks


  • Increased safety and accuracy for the surgeon in placing the electrodes,
  • Less invasive procedures: a decrease in bleeding, risk of infection and pain,
  • Optimum quality of the information collected by the depth electrodes, much better than that obtained by scalp electrodes,
  • A shorter operating time than with conventional surgery,
  • A broad exploration of the brain in both hemispheres.


  • Classical risks related to any sensitive surgical intervention,
  • Risk of hematoma in 2 to 3% of cases,
  • Risk of small skin infections provoked by the electrode.

Consult your physician for a complete list of benefits and risks, precautions, clinical results and other important medical information related to SEEG.

The information provided on this website is for information purposes only. It is not intended in any way to replace advice from your physician or other registered health professional.

With drug-resistant epilepsy, it is possible to envisage surgical treatment for adults and children. It is a highly complex procedure reserved for specialized, experienced centers. The principle is to be able to remove the area in the brain which is at the origin of all the seizures presented by the patient.

This type of operation is only possible if both the following conditions forming part of the pre-surgical evaluation have been previously met (this may take several months due to all the necessary precautions) :

  • It must be clearly established that all the epileptic seizures presented by the person come from a single, same area of the brain, whose contours are clearly defined. Failure to respect this condition may lead to therapeutic failure and the patient may continue to have seizures after the surgical intervention, due to the persistent presence of epileptic tissues.
  • It must be clearly established that an ablation of the epileptic region of the brain will not lead to any neurological deficit (apart from certain slightly incapacitating deficits which may be accepted by the patient before surgery, such as the amputation of a limited part of the visual field) or neuropsychological disorders (language, memory). This is sometimes a difficult stage, especially when the epileptic region is close to important functional areas.

Epilepsy may begin at any age. However, there are certain age groups which are at greater risk, particularly before the age of one and over 60 years old, the incidence increases proportionally with age.
How to behave when faced with an epileptic seizure

What to do :

  • Note down the exact time of the start and end of the seizure, as well as everything we observe,
  • Clear a space around the person so that he/she does not injure him/herself (in case of a convulsive seizure with a fall),
  • Protect his/her head (place a cushion or folded clothing under the person’s head),
  • Loosen his/her clothes, collar, belt,
  • Remove the person’s glasses if he/she is wearing any,
  • Put the person into lateral safety position (LSP) as soon as possible,
  • Stay with the person until the end of the seizure,
  • reassure the person during the period of confusion which may follow the return to consciousness.

What NOT to do :

  • impede the progress of the seizure,
  • intervene pointlessly when the person is having a seizure, as he/she might, in a state of semi-consciousness, perceive your actions as aggressiveness and react violently,
  • transport the person during the seizure except if he/she is in any immediate danger,
  • put something in the person’s mouth  (finger, spoon...),
  • give him/her something to drink or medication to swallow during the seizure.