Methods and systems for navigating medical devices are provided. A patient
is imaged while a medical device is moved within the patient. A position
(e.g., a location and/or orientation) of the moving medical device is
detected within a coordinate system (e.g., a three-dimensional coordinate
system), a position of the imaging field of view relative to the patient
is adjusted based on the detected medical device position, such that the
relevant tissue region of the patient is within the field of view. For
example, the field of view can be centered over the medical device or
centered just distal to the medical device portion. The direction of view
may be oriented at an angle perpendicular to the axis of the medical
device, e.g., for more accurately measuring the length of objects within
the field of view, or oriented at an angle parallel to the axis of the
medical device portion, e.g., for more accurately measuring the diameter
of the channel (e.g., blood vessel) in which the medical device is
disposed.