Tremblement Essentiel

Le tremblement essentiel, aussi appelé tremblement familial, est un trouble du mouvement fréquent, caractérisé par un tremblement à l’action (posture et mouvement). Une anomalie à la sortie du cervelet vers le thalamus créé une hyperactivité du thalamus et du cortex moteurs qui conduisent à un tremblement.

Notre approche est centrée sur l’interruption de cette connexion fonctionnant anormalement, sans toucher au thalamus. Cette méthode permet le couplage de l’efficacité et l’épargne des fonctions cérébrales et aussi, si nécessaire, une réduction du tremblement des deux côtés.

Des années de recherche -dans notre cas plus de 20 ans- des mécanismes des tremblements et leur contrôle adéquat, grâce à la sélection conséquente de cibles dans le cerveau, ont été nécessaires afin de savoir exactement où aller afin de procurer un soulagement efficace et épargnant contre le tremblement essentiel. La bonne nouvelle est que l’on peut diminuer les tremblements sans réduire les fonctions motrices, sensitives et cognitives. Le traitement peut être effectué sur les deux côtés du cerveau si nécessaire. L’efficacité moyenne du traitement à long terme se situe aux alentours des 80 à 90% de diminution des tremblements. Le profil de risque est faible et comprend essentiellement un risque de saignement dans la cible, estimé à moins de 1%. Le risque de dommage collatéral aux structures à côté de la cible est réduit de manière significative grâce au contrôle en temps réel de la température dans la cible, l’absence de déplacement mécanique par pénétration d’électrode et la précision de ciblage du système. Les effets négatifs à long terme du procédé de lésions par ultrasons focalisés peut être exclu de par le fait qu’il s’agit de coagulations thermiques, l’inocuité de ces denières ayant été démontrée maintes fois durant plus de 60 ans d’activité de neurochirurgie fonctionnelle à l’aide de thermocoagulations par radiofréquence. Les résultats à long terme des ultrasons focalisés ne sont pas encore disponibles ; toutefois, ils peuvent être estimés comme étant les mêmes que ceux obtenus à l’aide de la technique de pénétration par électrodes et thermocoagulation par radio fréquence, étant donné que les cibles utilisées sont exactement les mêmes. Ce fait à déjà été confirmé avec les premiers résultats post-opératoires des ultrasons focalisés à une année.

Résultats de traitement

Durant les diagnostics pré- et post-opératoires, nous demandons à nos patients de dessiner des lignes et des spirales. L’oeuvre d’art dessinée en diagnostic pré-opératoire est affichée ci-dessous. Cliquez sur l’image pour voir le diagnostic post-opératoire.

  • Patient 1

    1. Before
    2. After
  • Patient 2

    1. Before
    2. After
  • Patient 3

    1. Before
    2. After
  • Patient 4

    1. Before
    2. After

Témoignages de patients

Lettre publiée sur le site de la Fondation Nationale des Tremblements (UK) :

MR-Guided Focussed Ultrasound (MRgFUS) – A patient’s experience

– Dr Peter Bain’s patient letter

I am a 68-year-old man. As a child I had a mild tremor, which did not bother me very much. I learned to adapt my handwriting and became good at art and later became an architect. I began my architectural career with a world renown practice and later started my own award winning practice which I ran until October 2014 when I gave it up mainly because I could not cope with the disability of essential tremor.

My difficulty with essential tremor really began about 12 years go. My tremor began to worsen without reason. The tremor was worse on my right hand, my dominant side. I noted during times of stress the tremor would worsen. For example social occasions, writing cheques in banks, meetings, presentations etc. I began to avoid stressful situations and sought help from Consultant Neurologists. My tremor was diagnosed as hereditary essential tremor. My late mother had disabling tremor.

During 2008 I began various courses of drug therapies, first Gabpentin followed by Propranolol, Primidone, Topiramate and Mirtazapine for restless leg. The anti-tremor drugs tended to initially reduce the amplitude of the tremor but tended to leave me lethargic. After a period I tended to become resistant to each of the drugs and the tremor increased. When the tremor became disabling. I could not write, I could not pick up food with a fork except by stabbing it or using a spoon with two hands. I drank holding a cup with two hands and invented strategies for coping with day to day tasks such as leaning forearms on the table to assist with steading my hands. At times I found it difficult to control a computer mouse, repeatedly clicking unintentionally or unable to move the arrow where I wanted it to go. Each day was different, some days so bad I felt helpless.

I began to seriously consider the alternatives and discussed this with the Consultant Neurologist treating me at the time. Dr. Bain. The option to drugs available in this country is deep brain stimulation. The National Institute for Health and Clinical Excellence gives advice on safety using deep brain stimulation. The report notes complications could result in further surgery, infections, oedema, hardware failure, haemorrhage, dysarthia, speech disturbance, cerebal oedema and death. Other complications might include stroke, speech impairment, cognitive impairment, depression, suicide, and risk of injury during subsequent magnetic resonance imaging. It is for these reasons that I felt a great reluctance to undergo treatment using conventional deep brain stimulation. The alternative to this which Dr Bain introduced me to is MR guided focussed ultrasound treatment which is available commercially in Switzerland under Professor Dr. Daniel Jeanmonod at the Center for Ultrasound Functional Neurosurgery, Solothurn.

On September 2nd 2015 I underwent incisionless transcranial MR-guided Functional Ultrasound Neurosurgery.

A local anaesthesia is applied to the head to allow the fixation of a metal ring. The ultrasound helmet is positioned around my head with a silicone membrane closing the space between my head and the helmet to allow cooled water to circulate. The head is then brought in position in the MR bore so that more that 1000 ultrasound waves are focused for the procedure. The target in the brain is first exposed to low temperatures to determine the precise centering and then progressively increased to the final temperature to perform a left cerebello-thalamic tractotomy (thalamotomy or burn within the thalamus) and a right-sided centrum medianum thalamotomy. I was awake during the procedure, which lasted 3-4 hours with minor discomfort from the heat from the procedure. I stayed overnight in the clinic under observation, but apart from that felt no pain or discomfort.

Immediately following treatment, the tremor in my right arm and hand was completely cured and remains so. I am now able to write again in my original (pre-tremor) style of handwriting and to draw. I still have tremor in my left hand and continue to take anti-tremor drug therapy. A slight instability in my right leg during walking and a feeling of heaviness in both legs that were present after surgery has since disappeared.

Overall I am very happy with my postoperative experience, Apart from the above I felt well and able to visit the local museums and explore the town of Solothurn.

MR-guided Functional Ultrasound Neurosurgery has frankly given me back my life; My only regret is that I did not have the treatment sooner.

*

Dr Peter Bain MBBS MA(Oxon) MD FRCP
Reader & Honorary Consultant in Clinical Neurology