Implantation and antenna orientation of an implantable sensor

Abstract

A sensor system including an implantable sensor and an external transceiver. Aspects of the sensor system may provide improved implantation and antenna orientation of the implanted sensor. The sensor may include a sensor antenna, the transceiver may include a transceiver antenna. In some embodiments, the sensor antenna and/or transceiver antenna may include a first set of coils oriented in a first plane and a second set of coils oriented in a second plane that is different than the first plane. In some embodiments, the sensor may have a geometry that will prevent or reduce movement and/or rotation of the implanted sensor. For instance, in some embodiments, the sensor may be enclosed in silicon that contains antenna coils and/or include wings, a fluid filled sack, a swelling material, an expansion material, and/or arms.

We claim: 
     
         1 . A sensor system, comprising:
 a transceiver including at least one transceiver antenna; and   a sensor including at least one sensor antenna and a body, wherein said body is configured to expand after implantation to immobilize the sensor.   
     
     
         2 . The sensor system of  claim 1 , wherein the body of the sensor is composed of memory metal configured to transform from a first shape to a second shape. 
     
     
         3 . The sensor system of  claim 2 , wherein the first shape includes an approximately circular cross section and the second shape includes an approximately flat cross section. 
     
     
         4 . The sensor system of  claim 1 , wherein the body includes a substance configured to expand in response to a stimulus. 
     
     
         5 . The sensor system of  claim 4 , wherein the stimulus is water. 
     
     
         6 . The sensor system of  claim 4 , wherein the substance is acrylic acid. 
     
     
         7 . The sensor system of  claim 4 , wherein the stimulus is temperature. 
     
     
         8 . The sensor system of  claim 4 , wherein the substance is a liquid at room temperature and a gas at body temperature. 
     
     
         9 . The sensor system of  claim 4 , wherein the substance is 1,1,1,4,4,4 hexafluorobutane. 
     
     
         10 . The sensor system of  claim 1 , wherein the sensor includes a first substance and a second substance that expand when mixed together. 
     
     
         11 . The sensor system of  claim 10 , wherein the sensor includes a removable barrier separating the first and second substances. 
     
     
         12 . The sensor system of  claim 1 , wherein the body includes a first wing, a second wing and a removable seal coupled to an end of the first wing and an end of the second wing in a first orientation with an approximately circular cross section, and, upon removal of the removable seal, the first wing and second wing transform to a second orientation with an approximately flat cross section. 
     
     
         13 . A sensor comprising:
 a body including indicator molecules,   an antenna outside the body, and   a casing surrounding the body and antenna.   
     
     
         14 . The sensor of  claim 13 , wherein the casing has an oblong shape. 
     
     
         15 . The sensor of  claim 13 , wherein the casing has a flat, round shape. 
     
     
         16 . The sensor of  claim 13 , wherein the casing comprises a polymer material.