Contribution of 7 Tesla MRI of the Hypothalamus in the Diagnosis of Type 1 Narcolepsy

Inclusion Criteria for patients : 1. Diagnosis of narcolepsy type 1 according to the diagnostic criteria of the International Classification of sleep disorders version 3 (ICSD-3, American Academy of Sleep Medicine, 2014) including a mean sleep latency of less than 8 minutes on the iterative sleep latency test associated with at least two direct REM sleep onset and the presence of cataplexy, and a cerebrospinal fluid hypocretin assay of less than 110 pg/ml performed by the reference radioimmunology (RIA) technique. 2. Patient at least 18 years old 3. Patient followed at the Narcolepsy and Rare Hypersomnias Competence Center, Timone Hospital, Marseille 4. Patient having signed an informed consent 5. Patient who is a beneficiary of or affiliated to a social security system Exclusion Criteria for patient: 1. Diagnosis of type 1 narcolepsy according to ICSD-3 criteria but without hypocretin assay 2. Narcolepsy secondary to another neurological pathology or presence of a comorbid neurological pathology (multiple sclerosis, Steinert's myotonic dystrophy, head trauma, epilepsy) 3. Protected patient: pregnant or breastfeeding woman, adult under guardianship or curatorship 4. Contraindication to the realization of a 7T MRI: patient wearing a pacemaker, neurosurgical clips, artificial heart valve, surgical material or metal fragments in the body, dental or hearing prostheses, insulin pump, patient wearing an IUD, claustrophobic patient 5. Patient unable to maintain decubitus position for the duration of the MRI (= 50 minutes) Inclusion criteria for healthy volunteers: 1. Subject 18 years of age or older 2. Subject free of general illness, psychiatric disorders, and infectious, inflammatory, tumor, vascular, degenerative, or traumatic pathology of the central nervous system as determined during the medical interview. 3. Subject who has signed an informed consent ; 4. Subjects who are beneficiaries of or affiliated with a social security plan Exclusion criteria for healthy volunteers: 1. Protected subject: pregnant or breastfeeding woman, adult under guardianship or curatorship 2. Subjects presenting a contraindication to the realization of a 7T MRI: patient with a pacemaker, neurosurgical clips, artificial heart valve, surgical material or metal fragments in the body, dental or auditory prostheses, insulin pump, patient with an IUD, claustrophobic patient 3. Subject unable to maintain a decubitus position for the duration of the MRI (= 50 minutes)