CPT® Code 92570

Acoustic immittance testing, includes tympanometry (impedance testing), acoustic reflex threshold testing, and acoustic reflex decay testing

Acoustic immittance testing is a comprehensive evaluation process designed to assess the functionality of the middle ear, as well as to investigate potential disorders related to cranial nerve (CN) VIII, which is responsible for hearing and balance. This testing encompasses a series of specific procedures, including tympanometry, acoustic reflex threshold testing, and acoustic reflex decay testing. Each of these components plays a crucial role in diagnosing various conditions affecting the ear. Tympanometry, for instance, is a pivotal test that measures the compliance or flexibility of the tympanic membrane (eardrum). This measurement is essential for identifying issues such as fluid accumulation in the middle ear, negative pressure within the ear, perforations in the tympanic membrane, disruptions in the ossicular chain, and conditions like otosclerosis. During tympanometry, a device is inserted into the ear canal, and air pressure is varied to observe the eardrum's movement, which is graphically represented as a tympanogram. Acoustic reflex threshold testing evaluates the response of the stapedius muscle and tensor tympani to loud sounds, determining the softest sound that can trigger a reflex contraction of the stapedius muscle. This testing is crucial for understanding the middle ear's response to sound and can indicate potential dysfunction. Lastly, the acoustic reflex decay test assesses the integrity of CN VIII by measuring the response of the stapedius muscle to a sustained sound stimulus. A significant decrease in the muscle's response may suggest the presence of a retrocochlear lesion. Overall, acoustic immittance testing provides valuable insights into ear health and auditory function, enabling healthcare professionals to make informed decisions regarding diagnosis and treatment.