Tympanometry and acoustic reflectometry in ears with chronic retraction without effusion

Area of Science:

• Otolaryngology
• Diagnostic Imaging
• Audiology

Background:

• Accurate diagnosis of middle ear effusion (MEE) is crucial for appropriate treatment.
• Tympanometry (TYMP) and acoustic reflectometry (AR) are common tools for MEE assessment.
• Distinguishing MEE from conditions like chronic retraction without effusion can be challenging.

Purpose of the Study:

• To evaluate the test accuracy and predictivity of TYMP and AR parameters (reflectivity, curve angle) in identifying MEE.
• To compare diagnostic performance in ears with suspected effusion but no effusion confirmed by myringotomy, against normal ears and ears with confirmed effusion.

Main Methods:

• Study included 31 ears with chronic retraction (no effusion by myringotomy), 150 normal ears, and 150 ears with effusion.
• Effusion indicators: TYMP B tracings, AR reflectivity > 5, AR curve angle < 75 degrees.
• Combined test criteria for no effusion: non-B tracings with AR curve angle > 75 degrees.

Main Results:

• False positivity was significantly higher in chronic retraction ears compared to normal ears (P < 0.001) and effusion ears (P < 0.0001).
• Negative predictivity was lower for TYMP and AR alone compared to normal ears (P < 0.01), but perfect with the combined test.
• Positive predictivity decreased only with AR reflectivity in chronic retraction ears.

Conclusions:

• TYMP and AR alone have limitations in identifying ears without effusion among those suspected of otitis media.
• These methods exhibit higher false positivity and lower specificity/negative predictivity in clinical settings.
• The combined test improves negative predictivity but does not fully resolve the issue of high false positivity (low specificity).