Optimization of VIM Targeting in Essential Tremor Surgery

NCT ID: NCT03760406

Last Updated: 2025-02-25

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 22 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2019-03-18
• Study Completion Date: 2023-08-29

Brief Summary

Deep brain stimulation (DBS) for essential tremor is based on the intermedius ventralis nucleus of the thalamus (VIM) stimulation. This structure is however very difficult to target, as it remains invisible on imaging. The current procedure based on awake surgery with clinical and electrophysiological testings has several limitations that lead us to develop a probabilistic model to locate precisely the target. This study aims to show that asleep DBS surgery based on this new targeting method leads to at least the same clinical results than the classical procedure.

Detailed Description

The intermedius ventralis nucleus of the thalamus (VIM), which represents the target for deep brain stimulation (DBS) in essential tremor, still remains invisible on 1,5 tesla MRI (the only magnetic field available for stereotactic surgery). The target coordinates currently used are based on stereotactic atlases or mean coordinates from retrospective series. They are so imprecise that intra-operative clinical testing and micro-electrode recordings are mandatory to locate the exact position of the VIM. This procedure is long lasting, requires that the patient is awake, and increases the risk of intracerebral haemorrhage and nosocomial infections. Furthermore, some patients are not improved despite a DBS lead implanted in the electrophysiologically and clinically defined target. To overcome these limitations, investigators developed a probabilistic model based on data extracted from imaging of patients with particularly good outcomes after DBS surgery. This machine-learning model allows calculating to coordinates of the VIM according to the position of radio-anatomical landmarks with a mean precision of 1,65mm.

The aim of this study is to validate this new targeting method on a prospective cohort of patients. DBS surgery will be performed under general anaesthesia, without intra-operative clinical and electrophysiological testing, with a surgical robot and under CT-scan guidance (O-Arm ©).

Neurostimulation device programming will be performed as usual. Patients' tremor and quality of life will be evaluated pre and post-operatively at 3 months, according to the Fahn-Tolosa-Marin (FTM) scale and with an accelerometry recording (for tremor) and with the mPDQ-39 scale for quality of life. Surgical complications and side effects related to neurostimulation will be gathered all along the follow-up.

Conditions

Essential Tremor

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Severe essential tremor treated by DBS

Group Type: EXPERIMENTAL

Opti-VIM targeting in DBS surgery

Intervention Type: PROCEDURE

DBS surgery will be performed under general anaesthesia, without intra-operative clinical and electrophysiological testing, with a surgical robot and under CT-scan guidance (O-Arm ©). The VIM coordinates will be calculated with the probabilistic model that have been developed.

Interventions

Opti-VIM targeting in DBS surgery

DBS surgery will be performed under general anaesthesia, without intra-operative clinical and electrophysiological testing, with a surgical robot and under CT-scan guidance (O-Arm ©). The VIM coordinates will be calculated with the probabilistic model that have been developed.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Severe essential tremor despite the optimal medical management
• Age between 18 and 75 years
• Normal MRI scan
• Mattis Dementia Rating Scale (MDRS) score ≥ 130
• Affiliation to the social security
• Signed informed consent

Exclusion Criteria

• Depression (Beck Depression Inventory scale > 20)
• Contra-indication to surgery or general anesthesia
• Cerebral atrophy on MRI scan
• Pregnant or breastfeeding women

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University Hospital, Bordeaux

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Antoine BENARD, MD

Role: STUDY_CHAIR

USMR CHU de Bordeaux

Locations

CHU de Bordeaux

Bordeaux, , France

Hospices Civils de Lyon

Bron, , France

Countries

France

Other Identifiers

CHUBX 2018/32

Identifier Type: -

Identifier Source: org_study_id