The voice is a very important part of human communication. It is usually used on a daily basis and any alteration in the voice usually makes communication more difficult. It is desirable to be able to readily detect any pathologies, because, as in all diseases, the cure is easiest when the problem is detected in an early stage.
Alterations in the voice can be caused by many different things, including overuse (by teachers, singers, salespersons, announcers, etc.), problems in the vocal tract, and neurodegenerative diseases.
It used to be that the voice doctor would listen to the patients voice and decide if there was any reason for concern. If need be, the patient was examined using invasive means. In the beginning a small dentist mirror was used. Today voice doctors still listen to patient's voices, and if needed, video endoscopy of the larynx is used, quite often with a stroboscope.
Acoustic Analysis is beginning to find its place as a non-invasive technique to help the voice doctor identify if a pathology is present or not in the patient's voice. Several studies have shown that it is possible to separate normal voices from pathological ones with a high accuracy rate, usually well above 90%.