gms | German Medical Science

Achievements/questions: The ‘Admittance Response’ based method is an innovative technology based upon propriety patents and as such merits the closest clinical investigation. It enables the evaluation of the functional conditions of the middle ear through graphic and numerical representation of the response characteristics of the tympanic membrane without applying variations in air pressure to the ear canal.

The method adds further evolution to audiological diagnostics in the near future that goes beyond classic tympanometric screening.

Methods: The med·wave^® device is based on PLAI^® methodology, an acronym for ‘Pressure Less Acoustic Immittance’, primarily characterized by taking measurements without exerting pressure in the ear canal. It acquires the ear admittance response as a frequency of a sound varies between 100 and 3 kHz. The module & phase of the admittance response recorded in the ears of subjects belongs to one of the 3 groups shown in Figure 1 [Fig. 1] for children.

It presents a clear peak at a particular frequency (‘resonance frequency’). A frequency above 1 kHz indicates measurement error due to the incorrect probe positioning or the ear canal being occluded.

Several clinical trials have been carried out on pediatric & adult subjects and trials with children aged 0–24 months are currently ongoing.

One Italian hospital deemed most appropriate for clinical investigation with a pediatric focus was the Burlo-Garofolo IRCCS/Trieste, where data on a pediatric population aged 2–17 years old was collected.

The primary and first objective of study was to evaluate the capacity of the method to classify an ear in one of the following conditions or groups:

1.

Healthy ear;

2.

presence of Otitis MEdia;

3.

flacid ear or presence of perforated eardrum.

Results: The graphs of healthy subjects (children) showed that the measured admittance curves have low variability & being very compact. The mean resonance frequency was of 463 Hz (standard deviation -69 Hz). The Otitis Media (OME) admittance graphs show that the measurements have low variability and are very compact. Mean resonance frequency of OME subjects was of 617 Hz (Standard deviation -85 Hz).Finally, the graphs of ears presenting flacid tymp. or tympanic perforation report low variability, despite the small number of subjects until how have been available.

Summary: The clinical investigation demonstrated that the objectives posed were met and that the method supports significantly a distinction of healthy subjects from those with pathology in both: paediatric & adult groups. Among the parameters proposed and calculated, the best seems to be resonance frequency, which make it possible to significantly distinguish both the healthy group from the two groups of pathologies considered.