abstract |
An improved structure for an implantable medical device, such as an implantable pulse generator, is disclosed. The improved device includes a charging coil for wirelessly receiving energy via induction from an external charger. The charging coil in the device is located substantially equidistantly from the two planar sides of the device case. Because the coil is substantially equidistant within the thickness of the case of the device, the device's orientation within the patient is irrelevant, at least from the standpoint of the efficiency of charging the device using the external charger. Accordingly, charging is not adversely affected if the device is implanted in the patient with the wrong orientation, or if the device flips within the patient after implantation. Moreover, because the central portion of the device naturally corresponds to the largest lateral extent within the case due to the case's curved edges, the charging coil can be made larger in area, which improves its gain vis-à-vis the external charger. |