• 
  

  • Tympanometry directly measures the compliance of the tympanic membrane and ossicular chain, estimating middle ear pressure.

  
  

  • Tympanometry is primarily used to detect the presence of middle ear fluid, enhancing the diagnosis of acute otitis media and otitis media with effusion.

  
  

  • The procedure is also useful for detecting tympanic membrane perforation, ossicular chain disruption, and the patency of eustachian tubes.

  
  

  • Tympanometry is commonly performed as part of the early evaluation of hearing loss.

Absolute

• 
  

  • Age younger than 7 months. Studies have shown that tympanometry in infants 0–7 months of age is inaccurate due to the high compliance of the ear canal in these patients.

  
  

  • Recent ear surgery, such as stapedectomy, myringoplasty, or tympanoplasty.

Relative

• 
  

  • Blocked ear canal.

  
  

  • Ear canal with copious drainage.

  
  

  • Uncooperative or screaming patient.

• 
  

  • Otoscope.

  
  

  • Ear curettes.

  
  

  • Tympanometer with probe tips.

  
  
  
  
  • 
    

    • All instruments use acoustic energy to measure the combined admittance (compliance) of the ear canal and middle ear.

    
    

    • The most commonly used instruments deliver a probe tone of 225 Hz.

    
    

    • High-frequency instruments, sometimes used in infants, deliver a tone of 678 Hz.

• 
  

  • Before beginning the procedure, make sure that the probe assembly is securely fastened together; leaks will obscure the test results.

  
  

  • Also, ensure that the probe tube and tips are dry; wet equipment may clog, making it impossible to continue the test.

• 
  

  • Describe the procedure to the parents and patient and answer any questions.

  
  

  • Be sure to inform the patient that he or she will be hearing some brief, but potentially loud, sounds.

• 
  

  • The child needs to sit still during the procedure; if necessary, have the child sit on a parent’s lap for reassurance.