Otoscopic Investigations by Holographic Interferometry: A Fiber Endoscopic Approach Using a Pulsed Ruby Laser System

Otoscopy, as the name implies, deals with the visual inspection of the ear, especially the middle ear. Our research group is involved in this field, since we are interested in a holographic analysis of the vibration patterns of the eardrum in man. Our interest in such an analysis is caused by its cabability to investigate the sound transfer function of the middle ear, as well as to follow up healing processes after tympanoplastic surgery, and to provide the possibility of a differential diagnosis of disorders in the middle ear mechanics without the necessity to open the tympanic cavity surgically. The latter can be accomplished by comparison of “regular” and “pathological” patterns of tympanic membrane vibrations as could be proved by inestigations in man in vitro [1] as well as in vivo [2].