A medical imaging system comprises a teleoperated assembly including a medical instrument, a first imaging instrument, a second imaging instrument, a tracking fixture, and a processor. The first imaging instrument generates a first image of a field of view of the first imaging instrument and the second imaging instrument generates a second image. The tracking fixture is engageable along at least a portion of the second imaging instrument. The tracking fixture includes one or more features. The medical instrument is attachable to an attachment feature of the tracking fixture to maintain a known configuration of the medical instrument relative to the second imaging instrument. The processor is configured to determine a pose of the tracking fixture based on the one or more features of the tracking fixture and the first image.