Diagnostic Performance of the Resistance Index (RI) for the Assessment of Cerebral Vasoreactivity in Transcranial Doppler

Inclusion criteria

• The patient must have given their free and informed consent and signed the consent form
• The patient must be a member or beneficiary of a health insurance plan
• Stenosis ≥ 70% in diameter reduction in NASCET equivalent or occlusion of atheromatous origin of the cervical internal carotid artery, asymptomatic or symptomatic.
• Presence of a temporal window sufficient to record the homolateral and contralateral middle cerebral artery.
• Patient of legal age with free and informed consent.
• Patient who has signed the consent form.
• Patient affiliated or beneficiary of a health insurance plan.

Exclusion criteria

• The subject is participating in an interventional study, or is in a period of exclusion determined by a previous study
• The subject refuses to sign the consent
• It is impossible to give the subject informed information
• The patient is under safeguard of justice or state guardianship
• Contraindication to Acetazolamide Diamox® injection.
• Absence of temporal acoustic window (non visualization of the cerebral parenchyma, no recordable intracranial vessel).
• Insufficient temporal window (visualizable brain parenchyma, no recordable MCA)
• Internal or common carotid artery stenosis ≥70% or occlusion, contralateral to the primary lesion.
• Stenosis ≥50% of the middle cerebral artery homolateral or contralateral to the cervical lesion.
• Patient in exclusion period determined by another study.
• Patient under court protection, guardianship, or conservatorship.
• Patient refusing to sign the consent form.
• Patient unable to express his or her will (dementia, disturbed consciousness, etc.)
• Patient for whom it is impossible to give informed information for health reasons or because of a language barrier.
• Pregnant, parturient, or breastfeeding patient.