Συμβολή της τυμπανομετρίας πολλαπλών συχνοτήτων στη διάγνωση και πρόγνωση της εκκριτικής ωτίτιδας των ενηλίκων
Authors: Ριζά Φωτεινή 
Published: January 2014

Otitis media is characterized by the presence of effusion in the middle ear. It is one of the most common ear diseases in adults and it needs to be early diagnozed and treated, because of its possible adverse effects in middle ear function. Diagnosis of otitis media is based on history, otoscopy and conventional tympanometry. The later, although very popular, does not always identify the presence of middle ear effusion, which is thought to be almost certain in cases of type B tympanograms, whereas it can be quite reliably excluded in cases of type A tympanograms. However, in cases of transitional tympanograms (type As and C), any tympanometry-based predictions seem to be rather uncertain. On the other hand, Multiple Frequency Tympanometry is an extension of coventional tympanometry, which theoritically may provide more precise assessment of middle ear status. However, its clinical importance in the evaluation of otitis media remains to be explored. The aim of this study was: n to investigate the way that middle ear acts in adults, both under physiological conditions and under the presence of otitis media with effusion n to compare between the findings of simple tympanometry at 226 Hz and tympanometry at higher frequencies (678, 1000 ΠZ) and multiple tympanometry n to investigate the prognostic value of Multiple Frequency Tympanometry in diagnosis and prognosis of otitis media with effusion in adults. In the present study participated 165 adults (165 ears), divided in two groups: first group consisted of 83 normal hearing adults (83 ears) and served as control group, and second group consisted of 82 adults (82 ears) with otitis media with effusion. All subjects underwent both Conventional Tympanometry and Multiple Frequency Tympanometry measurements.All impedance measurements were performed by using Grason Stadle Middle Ear Analyzer GSI-33, version 2 and resulted to the following: 1) All ears with middle ear effusion in the myringotomy showed statistically significant lower absolute values, compared to the ears of the control group. (Values are resonance frequency (RF), phase angle ??, gradient of simple tympanogram at 226Hz and tympanometric height of tympanogram at RF) 2) Type B simple tympanogram represent the standard tympanometric expression of otitis media with effusion, whereas type C simple tympanogram resemble to normal ones and type As simple tympanogram shows intermediate behaviour between the type B and C tympanograms. 3) Presence of middle ear effusion in ears with transitional simple tympanograms (type C and As) ranged between 50% and 71,4%. 4) Underlying middle ear pathology seems to be highly related to the morphology of tympanograms recorded at resonance frequency (RF). In a percentage more than 95%, flat RF tympanograms derived from ears with effusion, whereas notched RF tympanograms derived from ears without effusion in a percentage more than 73%. 5) Using Multiple Frequency Tympanometry we studied the morphology of simple tymanograms type B for the Admittance (Y), the Susceptance (B) and the Conductance (G) as the frequency is getting higher from 226Hz to 678Hz and to 1000Hz. The result for the three parameters is that for all of them, their tympanograms tend to present notch as the frequency is getting higher. 6) Discriminal Statistical Analysis resulted to a specific arithmetic relation between resonance frequency (RF) and phase angle (??) values, with a cut-off point of -0.65, which enabled us, with high accuracy, to predict the presence of effusion in pathological ears (83% versus 67% of simple tympanometry). In conclusion, Multiple Frequency Tympanometry (MFT) seems promising for the diagnosis and investigation of several middle ear disorders. According to our results, MFT appears to evaluate quite accurately the presence of middle ear effusion. Therefore, we suggest the use of MFT in the evaluation of otitis media with effusion in adults, enriching the clinician’s diagnostic options, without replacing or underestimating the traditional methods and especially clinical examination, that has always been irreplaceable.