Devices and methods for treating obesity are provided, including intragastric devices and methods of fabricating, deploying, inflating, locating, tracking, monitoring, deflating, and retrieving the same. In one embodiment, a device includes a balloon capsule having a distal end, a catheter having a proximal end and a distal end, a connector, a light sensor, and a balloon valve. At least one optical fiber extends along the length of the interior of the catheter and through the valve such that a distal end of the optical fiber is positioned at a distal end of the balloon capsule when the catheter is placed within the balloon capsule, and such that a proximal end of the optical fiber can be received by the light sensor.