Farid, is a young parkinsonian who was diagnosed 6 years ago when he was 40 years old. He has severe tremors for which he is taking dopamine medication.
In Parkinson’s disease, there are 2 subthalamic nuclei which are located in the center of the brain and which are partly responsible for motor skills. Due to a lack of dopamine (a chemical messenger that ensures communication between neurons), the neurons in these nuclei are disrupted, they are overactive. It is this hyperactivity that causes the symptoms of the disease.
The disease with its tremors, but also stiffness, becomes more and more disabling in everyday life.
“That’s okay, that’s a lot more complicated if I want to take my drink, explains Farid. In my left leg, I also have delays in mobility. I have uncontrolled movements, tremors. at rest and I can’t control them. During the day I can go from the normal guy to the 82-year-old grandpa who has trouble walking “.
He returned to the hospital for a very impressive operation. His neurologist offered him deep brain stimulation which should help reduce his tremors.
This is a rare intervention, only 5 to 10% of Parkinson’s patients meet the criteria. This brain operation is heavy.
Farid : “Under stress, I have a bit of dyskinesia which is added to those which are already usual. Let’s say I’m a little impatient to sleep so I don’t think about it as much. It’s the first time I’ve had an operation for so long. I will be under general anesthesia, normally everything will be fine and it is true that he bumps on an organ which is sensitive so I hope he will take his time, I can not wait to see the result “.
Until recently, patients stayed awake to see live the effect of stimulation on their movements.
New operating technologies
The Rothschild Foundation Hospital relies solely on brain imaging without waking the patient, which is what reassured Farid.
As he falls asleep quietly on the operating table, the neurosurgeon studies the MRI of the brain which is a kind of mapping. He will implant electrodes in the subthalamic nuclei to stimulate them. It plunges into the heart of the brain, it is an extremely delicate operation.
Dr Vincent d’Hardemare, Adolphe de Rothschild Foundation Hospital: “To regulate this group of neurons, this subtalamic nucleus, the idea is to submit an electric current and from there the obligation to put a tool which is the electrode, the treatment being electricity. There, it is a representation of what we want to do. We aim for what is in green, the subtalamic nucleus. Once we have defined what were the interesting points, we will define the entry points. We will define them for, that all the way through the brain, avoiding fragile structures, we go through structures that do not have a major function.Classically we say that it is a grain of rice in the brain.A large grain of rice. “
Precision and thoroughness for this surgery
To reach the subtalamic nuclei and to avoid damaging the brain, everything is adjusted to the millimeter using tools that allow you to find the right angle and the right inclination. The surgeon will open the skull and insert guides through the brain to place electrodes there.
Before placing them, he will listen to the sound of neurons using microprobes. Each part of the brain emits very specific sounds thanks to a researcher who is the golden ear of the block and who locates the center of the subtalamic nucleus.
Laurent Goetz, electrophysiologist researcher, Adolphe de Rothschild Foundation hospital: “We hear these crackles of neurons. That’s typical of subthalamic. We hear the activity of the patient’s neurons. You see here there are 2 nice activities on the central electrode and the middle electrode so at the end, we are going to have a synthesis which will tell us that it is the best electrode. We decided that we would be on the central micro electrode. That is the final electrode, we measured so that we are at the right depth and we will descend quietly “.
Now that they have located the center of the subtalamic nucleus, the surgeon implants the 1st electrode, then the second using the same process.
After a scanner check to verify the correct positioning, the electrodes are connected to a box, a kind of pacemaker installed in the abdomen. It is he who will send the electric current for continuous stimulation. This stimulation will regulate and modulate the neurons of the subtalamic nuclei.
The operation took about 7 hours.
Farid is fine, he is slowly recovering. Its neurologist, Doctor Cécile Hubsch, makes the 1st adjustments of the electrodes to gradually lower his tremors.
Dr Cécile Hubsch, neurologist: “There is a little tremor happening so I increase the amplitude a little bit and we try. That’s very good, impeccable. For the moment we have a fairly standard setting and we increase very slowly.
It takes an average of 3 months to have the final result of the operation. Farid is already very happy with the 1st results.