Brain Tissue Imprint

Study Overview
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Brief Summary
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This exploratory study aims to validate the collection and analysis of brain tissue imprints during the DBS by using a CE marked Medical Device in patients presenting one of the following five disorders: Parkinson's disease (PD), essential tremor (ET), dystonia (DYS), Obsessive compulsive disorder (OCD) and Tourette Syndrome (TS). The Brain Tissue Imprint project is focused on the DBS surgical procedure, which constitutes an appropriate method to collect brain tissue imprints by taking advantage of the direct and transitory contact at the extremity of the dilator with adjacent brain tissue. Indeed, during this step, micro-fragments of brain material spontaneously adhere to the dilator tip. It is this imprinting process that allows to collect what is defined as brain tissue imprints. This approach is part of the standard surgical procedure of the SCP without major change or complications.

Detailed Description
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Deep brain stimulation (DBS) has become the standard functional neurosurgery treatment for drug resistant Parkinson's disease (PD) patients. It has also demonstrated its efficacy to treat various movement disorders as well as neurological and psychiatric disorders. The subthalamic nucleus (STN), the globus pallidus internal (GPi) or the ventral intermediate nucleus of the thalamus (VIM) are the major targets of DBS. Access to pathological brain tissue in living PD patients or other neurological diseases is a key issue for the discovery of new therapeutic targets and the development of potential curative therapies. In this context, DBS offers a unique access to the pathological brain. In the standard surgical procedure, to prepare the way for the final electrode, the surgeon uses a dilator that is lowered gently through the cerebral parenchyma up to the target. It has been shown that during this step, brain tissue fragments adhere to the extremity of the dilator. However, the major drawback of the standard dilator lies in the fact that its end is in contact with several brain regions before reaching the targeted nucleus. Therefore, it is difficult to guarantee the origin of the collected tissue micro-fragments. In order to optimize the specificity of the harvested imprints, the investgator will use a dedicated CE marked medical device that consists of a guide tube and a stylet instead of the dilator used in DBS surgical procedure. The objective of this study is to validate brain tissue imprints collection in PD, ET, DYS, OCD and TS. The BTI will be specifically collected from the targeted implantation site corresponding to the STN, the GPi and the VIM. Moreover, the tip of the electrode (and therefore the BTI) often reaches the substantia negra pars compacta (SNpc) because of its proximity with the STN. The ability to perform BTI in the SNpc is of highly interest since it is the structure containing the neurons that degenerate gradually and massively throughout the pathological process of Parkinson's disease.

Official Title
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Stimulation cérébrale Profonde et Empreinte Tissulaire : Une Nouvelle stratégie Pour la Recherche Biologique in Vivo Dans la Maladie de Parkinson, Les TOC, la Dystonie, le Tremblement Essentiel et le Syndrome Gilles de la Tourette.

Conditions
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Parkinson Disease, Neurologic Disorder

Intervention / Treatment
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* Device: Brain Tissue Imprint


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Eligible patients for deep brain stimulation surgery Patients affiliated to social security or benefiting of a similar insurance scheme Patients having signed a consent to participate to the study Exclusion Criteria: Patient not eligible for deep brain stimulation surgery Pregnant women or nursing mothers Persons deprived of liberty by judicial or administrative decision Persons unable to express their consent or legally protected Persons in period of disqualification for another interventional research

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Brain Tissue Imprint<br>Evaluation and validation of the samples collected during the brain tissue imprint procedure using a CE marked Medical Device in patients presenting one of the following five disorders: Parkinson's disease (PD), essential tremor (ET), dystonia (DYS), Obsessive compulsive disorder (OCD) and Tourette Syndrome (TS). | Device: Brain Tissue Imprint<br>* Brain Tissue Imprint procedure (BTI) is performed during DBS surgery. Before the implantation of the electrode, the surgeon uses a dilator. It is a rigid stylet with a blunt end, intended to prepare the way for the final electrode. This dilator is lowered gently through the cerebral parenchyma up to the target then removed to be replaced by the electrode. In our BTI study, the standard dilator used in DBS surgery will be replaced by a CE marked Medical Device. This brain imprint kit will be used for each hemisphere. The procedure is the following: The guide tube with the first stylet is set up to the target Withdrawal of the first stylet and insertion of the second stylet for one minute to have a spontaneous and adequate tissue adhesion Withdrawal of the guide tube containing the stylet. This last step will prevent contamination of the harvested material on the stylet during the removal.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Validation of the collection of brain tissue fragments on the BTI device during the DBS surgical procedure | Visual assessment of the presence or the absence of a tissue micro-fragment. The presence or absence of blood contamination will also be notified | The evaluation of the collection of brain tissue fragments will be performed in the surgery room when the BTI device is removed from the patient and inserted in the collection tube | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Deep Brain Stimulation, Tissue harvesting, Molecular analysis - Proteomics