[Objective Audiological Test Procedures: Indications and Differential Diagnostics].

Diagnostics of hearing loss comprises subjective and objective methods and is successfully applied since many decades. This article introduces into the methods of impedance audiometry, otoacoustic emissions, auditory evoked potentials and electrically evoked potentials and describes the respective methodologies. Using an exemplary case, in this article we guide through all stages of objective audiological diagnostics and introduce the scientific and technical background, the application and evaluation of the findings of the objective test procedures. An application pathway for objective audiometric diagnostic tools is also described, including newborn hearing screening, differential diagnostics of hearing loss, auditory neuropathy, sudden sensorineural hearing loss, vestibular schwannoma and pediatrics patients. Finally, the application to patients with active middle-ear implants and cochlear implants is described.