Instrument with multiple sensing channels for automated ventilation tube insertion on tympanic membrane

Otitis media with effusion (OME) is a common ear disease occurring in adults and children when the middle ear is infected, resulting in accumulation of fluid in the middle ear space and leading to complications. The current treatment is to surgically insert a ventilation tube into the tympanic membrane (TM) to bypass the Eustachian tube in draining fluid. An office-based robotic instrument allowing fast tube insertion has been designed in an earlier work of the authors. However, as the malleus bone is attached to the inner surface of the TM, this part of the membrane is to be avoided during the insertion process and the previous instrument relies on manual manipulation to locate the suitable insertion spot. In this paper, an instrument equipped with multiple sensing channels is developed to accomplish the procedure automatically. Leveraging on the machine vision and tactile sensing, the new instrument is able to manipulate the insertion channel to move effectively in the ear canal, without hitting the malleus bone to the desirable insertion spot accurately. A switching control mechanism is proposed to integrate the sensing channels and working stage. Pre-clinical tests on the harvested pig ears are carried out to verify the feasibility and efficacy of the proposed approach.