Neuromodulation in Patients With Neuropathic Pain and Depression.

Neuromodulation in Patients With Neuropathic Pain and Depression: a Cross-over Study Between Two Targets in Transcranial Magnetic Stimulation, the Primary Motor Cortex and the Dorsolateral Prefrontal Cortex.

High-frequency repetitive transcranial magnetic stimulation of the primary motor cortex has shown its effect on refractory neuropathic pain, and rTMS of the dorsolateral prefrontal cortex is commonly used for treatment-resistant depression.

The treatment for patients suffering from neuropathic pain and depression, concomitantly, still needs to be studied, as there are some specificities in both symptoms and brain functional MRI.

This project is a cross-over study for these patients, including 4 sessions of either M1 or DLPFC rTMS, a wash-out period, followed by 4 sessions of the other stimulation site, to assess the efficiency of a DLPFC rTMS for neuropathic pain with a comorbid depression. Besides pain intensity and quality, patient's mood, quality of life, and catastrophizing will be assessed.

Inclusion Criteria:

• Central or peripheral neuropathic pain
• Chronic pain (present for more than 6 months) with intensity greater than or equal to 4/10 on the numerical scale
• Pain present on a daily or near-daily basis (at least 4 days a week)
• Patient not completely relieved by recommended drug treatments for first- and second-line neuropathic pain
• Stable analgesic treatment (no new treatment or dosage adjustment) for at least one month, and will not need to be modified for the duration of the study.
• Patient with a depressive episode characterized according to DSM V criteria
• Indication for motor cortex rTMS by a neurologist
• Patient can be followed for the entire duration of the study
• Patient having received informed consent to participate in the study, and having co-signed a consent form with the investigator
• Member or beneficiary of a social security scheme

Exclusion Criteria:

• Industrial accident or litigation
• Contraindication to rTMS or MRI (seismotherapy treatment since the previous month; epilepsy and/or history of epilepsy; history of head trauma; neurosurgical lesion; intracranial hypertension; intracerebral metal clip; piercing; pacemaker; insulin pump; metal prosthesis; pregnant or breast-feeding woman; claustrophobia)
• Drug or psychoactive substance abuse
• Neuropathic pain in the context of a progressive pathology (HIV, cancer, systemic disease disease)
• Presence of other pain more severe than that justifying inclusion
• Patient unable to understand informed consent
• Patient unwilling or unable to stop treatments prohibited during the study
• Patient participating in another research protocol involving a drug within the 30 days prior to inclusion
• Patient deprived of liberty or under legal protection (guardianship, curatorship, safeguard of justice safeguard, family safeguard)
• Minor patient