Acoustic Immittance Measures for Hearing
DESCRIPTION
Audiometric studies are diagnostic tests that evaluate hearing loss. Among these studies are acoustic immittance measures. Acoustic immittance measures are a battery of tests including tympanometry, acoustic reflex test, and static acoustic impedance. These tests may be used to assess the hearing of neonates and other children too young to cooperate in the audiometric testing of functional hearing loss.
Tympanometry is used to detect conductive hearing loss in infants, children and adults, although a sensorineural loss may also be present. A probe that emits continuous sound is fitted into the entrance of the outer ear canal. Air pressure is introduced into the ear canal making the eardrum move back and forth. This test measures the mobility of the eardrum, thus the ability of the middle ear to conduct sound. It is useful in the identification of fluid in the middle ear, perforation of the eardrum, wax blocking the ear canal and in the anatomic localization of facial nerve paralysis.
Acoustic reflex test measures the ability of a tiny muscle in the middle ear to contract when a loud sound occurs. The loudness level, measured in decibels at which the acoustic reflex occurs and/ or the absence of the acoustic reflex, provides diagnostic information. This is used to identify the location of the auditory pathway defect. The absence of the acoustic reflex may indicate, among other things, lesions of the middle ear, acoustic tumors, otosclerosis, facial nerve involvement of the probe ear side, and surgical removal or congenital absence of the stapes.
A static acoustic test measures the physical volume of air in the ear canal. It is useful in identifying a perforated eardrum or the openness of ventilation tubes.
POLICY
Acoustic immittance measures used to screen for hearing impairment in infants (birth through 24 months) is considered medically necessary.
Acoustic immittance measures when used to test for hearing impairment in adults, children and infants is considered medically necessary if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
See also:
MEDICAL APPROPRIATENESS
Acoustic immittance measures are considered medically appropriate for, but not limited to, any of the following conditions:
Bacterial meningitis
Cochlear otosclerosis
Congenital anomalies
Exposure to intense noise
Facial nerve paralysis (Bell's Palsy)
Fractures of the temporal bone or trauma affecting the central auditory pathways
Hearing loss
Labyrinthitis
Ménière's disease
Neoplasms of the auditory or central nervous system
Otitis media
Ototoxic drugs
Surgery involving the auditory and/or central nervous system (e.g., skull-based tumors such as acoustic neuroma and meningioma)
Tinnitus
Vertigo (dizziness)
ADDITIONAL INFORMATION
The following screening program for infants is recommended by the American Academy of Pediatrics 2007 Position Statement:
Begin screening for hearing loss no later than one month of age
Include a comprehensive audiological evaluation before three months of age for infants who fail the initial screen
Refer infants with confirmed hearing loss for age-appropriate diagnostic testing before six months of age
Refer infants for effective intervention by qualified professionals with an expertise in hearing loss and deafness in infants and children
Well-child visits should Include ongoing surveillance of communicative development beginning at two months of age regardless of previous hearing-screening outcomes or the presence of risk factors
SOURCES
110th Congress: 1st Session: S. 1069: (2007, March). Early hearing detection and intervention act of 2007. Retrieved January 14, 2008 from http://thomas.loc.gov.
American Academy of Pediatrics. (2007). Year 2007 Position Statement: Principles and guidelines for early hearing detection and intervention programs. Retrieved January 14, 2008 from http://aappolicy.aappublications.org/cgi/reprint/pediatrics;120/4/898.pdf.
American Speech-Language-Hearing Association. (2004). Guidelines for audiologic assessment of children from birth to 5 years of age. Retrieved January 14, 2008 from http://www.asha.org/docs/pdf/GL2004-00002.pdf.
American Speech-Language-Hearing Association. (2007). Hearing assessment. Retrieved January 14, 2008 from http://www.asha.org/public/hearing/testing/assess.htm.
American Speech-Language-Hearing Association. (2007). Hearing screening. Retrieved January 14, 2008 from http://www.asha.org/public/hearing/testing.
Bagai, A., Thavendiranathan, P., & Detsky, A. S. (2006). Does this patient have hearing impairment? JAMA, 295 (4), 416-428. Abstract retrieved January 15, 2008 from PubMed database.
BlueCross BlueShield Association. Medical Policy Reference Manual. (4:2005). Evaluation of hearing impairment (9.01.02). Retrieved January 14, 2008 from BlueWeb. (6 articles and/or guidelines reviewed)
BlueCross BlueShield of Tennessee network physicians. February 2008.
Hayes. Medical Technology Directory. (2005, July). Neonatal hearing screening. Retrieved January 14, 2008 from www.Hayesinc.com/subscribers. (62 articles and/or guidelines reviewed)
National Guideline Clearinghouse. (2003, February). Hearing impairment in infants and children: Recommendations beyond neonatal screening. Retrieved January 14, 2008 from PubMed database.
Palmer, C. V., & Ortmann, A. (2005). Hearing loss and hearing aids. Neurologic Clinics, 23 (3), 901-98.
Probst, R. (2007). Audiological evaluation of patients with otosclerosis. Advances in Otorhinolaryngology, 65, 119-126. Abstract retrieved January 14, 2008 from PubMed database.
ORIGINAL EFFECTIVE DATE: 10/1998
MOST RECENT REVIEW DATE: 7/12/2008
ID_BT
Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.
This document has been classified as public information.