Optical fiber pressure sensor guidewire

In an example, this document discloses an apparatus for insertion into a body lumen, the apparatus comprising an optical fiber pressure sensor. The optical fiber pressure sensor comprises an optical fiber configured to transmit an optical sensing signal, a temperature compensated Fiber Bragg Grating (FBG) interferometer in optical communication with the optical fiber, the FBG interferometer configured to receive a pressure and modulate, in response to the received pressure, the optical sensing signal, and a sensor membrane in physical communication with the FBG interferometer, the membrane configured to transmit the received pressure to the FBG interferometer.