gms | German Medical Science

Objectives: There are some indications from literature or personal experience that the tensor tympani muscle might play a role in some ear symptoms like “fullness”, certain cases of tinnitus, even slight hearing loss, or Menière-like findings. For proving such theories there must be tools to clinically diagnose the functional state of the muscle, particularly its tonic contraction. In an experimental study we looked for such indicators in terms of visual or functional (impedance audiometry) effects during simulated tensor contractions.

Methods: In 5 fresh temporal bones special preparations were performed for applying traction forces simulating tensor contractions. Points of application were either the isolated muscle itself, its tendon, or the malleus neck. Effects were observed visually via an endoscope or by impedance audiometry using multiple frequency tympanometry.

Results: During simulated tensor traction the aspect of the tympanic membrane changed slightly: there was some inward movement of the malleus handle. However, such effects were only identifiable during the pulling-action or in direct comparison between the “contracted” or “relaxed” state. Tympanometry revealed a decrease of the peak amplitudes and a shift of the middle ear resonance towards higher frequencies during simulated contractions.

Conclusions: Our results show that in clinical practice it should not be easy to diagnose tonic contractions of the tensor tympani muscle. On the other hand it seems worth searching for such indications. It seems almost forgotten that some years ago Klockhoff introduced the term “tensor tympani syndrome” which included most of the non-specific symptoms mentioned above. Based on our experimental results a clinical study will be started which should clarify the diagnostic relevance of indicators for tonic tensor muscle contractions.