Method and system for positioning a sensor

A method for attachment of a bispectral index sensor to a patient, the method comprising:

• positioning a first electrode on a patient's temple;
• positioning a second electrode on a patient's forehead directly above a patient's eye;
• positioning a third electrode on a central portion of the patient's forehead;
• and
• positioning a fourth electrode on the patient's forehead between the second electrode and the third electrode, wherein the bispectral index sensor comprises a substrate supporting the electrodes and having a bridge disposed between the first and second electrodes, wherein the bridge is sufficiently rigid to prevent the first and the second electrodes from moving laterally relative to a longitudinal axis of the sensor.

A monitor comprising:

• a display unit configured to display at least one help screen to facilitate a correct placement of a sensor on a patient, wherein the sensor comprises an elongated substrate having a first end portion and a second end portion and having a first electrode disposed on the first end portion and a second electrode disposed on the second end portion, the first electrode and the second electrode being separated from one another by a distance substantially equal to a distance from a patient's temple to a central portion of a patient's forehead, such that the first electrode is adapted to be placed on the patient's temple and the second electrode is adapted to be placed on the central portion of the patient's forehead, and a third electrode positioned on the substrate to be placed on the patient's forehead directly above a patient's eye when the first electrode is placed on the patient's temple and the second electrode is placed on the central portion of the patient's forehead, and a fourth electrode being positioned on the substrate between the second electrode and the third electrode and being adapted to be placed on the patient's forehead between the second electrode and the third electrode, wherein the at least one help screen comprises at least one help screen illustrating a representation of a portion of the patient's head and proper placement of the sensor on the portion of the patient patient's head.