Tensometrie – Konzept und erste Ergebnisse einer neuen Technik der Tubenfunktionsmessung über hochflexible Dehnungsmessstreifen

Summary

Background: So far there is no suitable method to record the function of the Eustachian tube (ET), because all available techniques either do not reflect physiological requirements or just record "snapshot" of single openings of the ET.

A new concept is introduced, by which the effect of tube function on the tympanic membrane (TM) can be measured. In- and outward movements of the TMs are recorded by means of highly flexible foil strain gauges ("Tensometry").

Methods: First prototypes of thin measuring foils were manufactured, which could be attached to the TM and fixed by water adhesion forces. The actual foil strain gauges were printed on thin PET-foils in a photo-chemical procedure. First practical tests were carried out on volunteers in pressure chambers.

Results: The prototypes were able to record deviations of the TM reproducibly and without causing pain to the test person. It was possible to detect slow deflections of the TM due to relative pressure differences between the middle ear and the environment, and also fast reset movements due to openings of the ET.

Discussion: After demonstrating the basic feasibility of the tensometry method, we now focus on improving the wearing comfort and the technique for picking up the measuring signals. A method of wireless recording of such signals is presently being developed, which will greatly facilitate the measuring procedure.

Literatur

• 01 Koch U . Pau HW . Tubenfunktionsstörungen. In: Naumann HH, Helms J, Herberhold C et al. (Hrsg). Oto-Rhino-Laryngologie in Klinik und Praxis.  Stuttgart: Thieme. 1994;  564-581
• 02 Pau HW . Trommelfellretraktionen – Entstehungsursachen, Bedeutung, klinische Konsequenzen.  Laryngo-Rhino-Otol. 2001;  80 1-2
• 03 Koch U . Opitz HJ . Pau HW . Tubenfunktion und Mittelohrdruck bei adhäsiven Trommelfellen.  Laryng Rhinol. 1977;  56 156-159
• 04 Pau HW . Koch U . Tympanometrische Untersuchungen an Mittelohrmodellen.  Arch Otorhinolaryngol. 1978;  221 261-267
• 05 Leuwer R . Koch U . Anatomie und Physiologie der Tuba auditiva.  HNO. 1999;  47 514-523
• 06 Bluestone CD . Hebda PA . Alper CM . et al . Recent advances in otitis media. 2. Eustachian tube, middle ear, and mastoid anatomy; physiology, pathophysiology, and pathogenesis.  Ann Otol Rhinol Laryngol Suppl. 2005;  194 16-30
• 07 Zehlicke T . Pau HW . Schmidt W . et al . Die Tensometrie – eine neue Technik zur Begutachtung der Tubenfunktion bei Tauchern und Piloten.  Biomedizinische Technik. 2006;  345-346
• 08 Di Martino E . Nath V . Telle A . et al . Examination of the Eustachian Tube Activity with Perfect Sequences.  Laryngo-Rhino-Otol. 2008;  Feb. 20 [Epub ahead of print]
• 09 Di Martino E . Thaden R . Krombach GA . et al . Funktionsuntersuchungen der Tuba Eustachii Aktueller Stand.  HNO. 2004;  52 1029-1040
• 10 Pau HW . Zehlicke T . Schmidt W . et al . Tensometry as a new technique for examining distensibility of tympanic membranes and functionality of the Eustachian tube.  Biomed Techn. 2005;  50 568-569
• 11 Weinrich N . Seide K . Wendlandt R . et al . A System for Wireless Monitoring of Loads Acting on Internal Fixators In Vivo.  Biomed. Technik. 2005;  50 1535-1536
• 12 Koch U . Middendorf F . Direkte kontinuierliche Bestimmung des Mittelohrdruckes.  Laryngo-Rhinol-Otol. 1979;  58 424-434
• 13 Koch U . Die Bedeutung der Tubenmanometrie zur Beurteilung der Tubenfunktion.  Arch Otorhinolaryngol. 1983;  237 263-271