Signal strength indicator for adjusting communication in a medical implant
It is critical in an inductively link medical implant, such as a visual prosthesis or other neural stimulator, to adjust the external coil to a location to maximize communication between the external coil and internal coil. Converting the signal strength between the coils to a signal easily discernible by a clinician, preferably an audible tone, facilitates the adjustment of the external coil to a preferred location.
1. A method of fitting a medical device comprising:
providing medical device having
an implantable portion including an internal coil; and
an external portion including an
external coil,
an adjustable mounting system supporting the external coil, and
a real time indicia of a inductive coupling strength between the internal coil and
the external coil;
adjusting the position of the external coil to the point greatest signal strength guided by the real time indicia; and
fixing the mounting system to prevent movement of the external coil.
2. The method according to claim 1 , wherein the real time indicia is an indicia of signal strength of a signal transmitted from the internal coil to the external coil.
3. The method according to claim 1 , wherein the real time indicia is an audible tone.
4. The method according to claim 3 , wherein the audible tone is higher in pitch to indicate a stronger inductive coupling strength and lower in pitch to indicate a weaker inductive coupling strength.
5. The method according to claim 1 , wherein the adjustable mounting system includes means for fixing the adjustable mounting system at a location of maximum inductive coupling strength.
6. The method according to claim 1 , wherein the medical device is a visual prosthesis.
7. The method according to claim 6 , wherein the mounting system mounts the external coil to a glasses frame.