Passive sensors and related structures for implantable biomedical devices

A biomedical implant for implantation inside a patient comprising:

• a wall enclosing at least a portion of the implant, the wall including:
• a first stratum;
• a second stratum conformal with the first stratum;
• an interlayer between the first and the second strata, the interlayer including a structure that produces capillary pressure in an infiltrating fluid in response to rupture of at least one of the first stratum and the second stratum resulting in entry of the infiltrating fluid into the interlayer;
• and
• a sensor system that includes:
• a first device including a detector and a first communication circuit, the detector being exposed to the interlayer, and including fluid-sensing circuitry to detect a presence, if any, of the infiltrating fluid, and the first communication circuit being operative to initiate a first wireless transmission containing a detection state indicator of the detector;
• and
• a second device physically isolated from the first device, and including a second communication circuit interactive with the first device to receive the first wireless transmission, and to initiate a second wireless transmission to communicate the detection state indicator to a reader external to the patient.