Patent ID: 8147544

Claim:
A therapeutic appliance configured for implantation into a cylindrically-shaped fenestration that pierces a wall of a cochlea of a subject, the fenestration including an outer section and an inner section which is smaller in diameter than the outer section, the fenestration also including an annularly-shaped well floor that spans between one edge of the outer section of the fenestration and one edge of the inner section thereof, the therapeutic appliance comprising: an outer barrel configured to be inserted into and to be fixed firmly in the outer section of the fenestration at a distal end, the outer barrel having a outer barrel diameter dimension about a longitudinal axis; an annularly-shaped shelf configured to be within the wall of the cochlea, the annularly-shaped shelf coaxial with and adjacent to the outer barrel along the longitudinal axis, the shelf having an outer edge which abuts with an edge of said outer barrel and having a shelf diameter dimension about the longitudinal axis, wherein the shelf diameter dimension is smaller than the outer barrel diameter dimension, said shelf configured to be juxtaposed with the well floor of the fenestration upon insertion of the therapeutic appliance fully into the outer section of the fenestration; and an inner barrel configured to be at a proximal end closest to the scala tympani region and opposite to the distal end, the inner barrel coaxial with the shelf and the outer barrel along the longitudinal axis, the inner barrel having an inner barrel diameter dimension about the longitudinal axis, wherein the inner barrel diameter dimension is smaller than the shelf and outer barrel diameter dimensions, the inner barrel having an edge which abuts with an inner edge of said shelf and that projects away from said outer barrel of the therapeutic appliance, said inner barrel configured to be inserted into and to be fixed firmly into the inner section of the fenestration in communication with a scala tympani region.