Changes in the MRI Signal in Patients With Benign Tumors of the Brain and Meninges Treated With Proton Therapy: Impact of TEL and the Biological Dose Received

Inclusion Criteria: * Histologically proven or highly probable grade I meningiomas, histologically proven grade II meningiomas. * Only meningiomas of the anterior and middle floors of the base of the skull are included. * Indication of proton therapy retained in RCP and / or proton therapy technical staff (Caen site) * Patient aged 18 or over * Patient affiliated to a social security scheme * Signature of informed consent before any specific procedure related to the study Exclusion Criteria: * History of brain or face irradiation. * Implant or foreign body that can alter MRI imaging. * Contraindication to MRI (pace maker, claustrophobia ...) - Hypersensitivity to gadoteric acid, to meglumine or to any medicine containing gadolinium * Genetic radio sensitizing syndrome * Known neurological comorbidities (stroke, Parkinson's, etc.) that may impact MRI data. * Simultaneous participation in a therapeutic clinical trial * Patient unable to undergo the trial follow-up for geographic, social or psychopathological reasons * Pregnant or breastfeeding women * Persons deprived of their liberty (see article L 1121-6 CSP), * Adults who are the subject of a legal protection measure or unable to express their consent (see article L 1121-8)