An optical device includes an optical waveguide through which light propagates and a micro-resonator structure including an optical sensor. In one embodiment, the release member is connected for sliding movement between releasing and retaining positions, and the housing contains a reset access opening. The front gripper is configured to straighten an inner lumen of the balloon catheter. The bottom-forming part is configured and arranged to deform the bag in contact with the bag receiving part to form a bottom portion of the bag into a prescribed shape.