A medical system (50, 100) comprising: at least one processor (32, 62, 120) programmed to: receive patient-specific data of a patient, the patient-specific data including image and/or map data; visually display at least some of the patient-specific data to a user of the medical system (50, 100) on a monitor (70, 128); and frequency modulate an aural signal to convey quantitative data to the user using the sense of sound, the signal being modulated based on the quantitative data, the frequency modulating including modulating a pitch of the aural signal by increasing or decreasing the pitch to convey the quantitative data as additional information regarding displayed images and/or maps that is not visually available to the user in order to facilitate navigation of a needle or shaft through displayed images and/or maps and/or intervention using displayed images and/or maps, and an aural device for conveying the aural signal to indicate, while navigating the needle or shaft, one of - a navigation property or a change in a navigation property, - potential obstacles in the path of the needle or shaft - proximity to adjacent anatomical structures. at least one processor (32, 62, 120) programmed to: receive patient-specific data of a patient, the patient-specific data including image and/or map data; visually display at least some of the patient-specific data to a user of the medical system (50, 100) on a monitor (70, 128); and frequency modulate an aural signal to convey quantitative data to the user using the sense of sound, the signal being modulated based on the quantitative data, the frequency modulating including modulating a pitch of the aural signal by increasing or decreasing the pitch to convey the quantitative data as additional information regarding displayed images and/or maps that is not visually available to the user in order to facilitate navigation of a needle or shaft through displayed images and/or maps and/or intervention using displayed images and/or maps, and receive patient-specific data of a patient, the patient-specific data including image and/or map data; visually display at least some of the patient-specific data to a user of the medical system (50, 100) on a monitor (70, 128); and frequency modulate an aural signal to convey quantitative data to the user using the sense of sound, the signal being modulated based on the quantitative data, the frequency modulating including modulating a pitch of the aural signal by increasing or decreasing the pitch to convey the quantitative data as additional information regarding displayed images and/or maps that is not visually available to the user in order to facilitate navigation of a needle or shaft through displayed images and/or maps and/or intervention using displayed images and/or maps, and an aural device for conveying the aural signal to indicate, while navigating the needle or shaft, one of - a navigation property or a change in a navigation property, - potential obstacles in the path of the needle or shaft - proximity to adjacent anatomical structures. - a navigation property or a change in a navigation property, - potential obstacles in the path of the needle or shaft - proximity to adjacent anatomical structures.