A system for determining blood flow to and from the brain of a patient includes a plurality of magnetic elements configured to be positioned adjacent to the neck of the patient and apply at least one magnetic field to the neck of the patient. The system includes a plurality of electrodes configured to be in electrical contact with the neck of the patient, the electrodes configured to detect a voltage induced across the neck of the patient responsive to the applied magnetic field and blood flow through the neck of the patient. The system includes a support component for holding the plurality of magnetic elements and the plurality of electrodes at the neck of the patient.