Systems and methods for registration of a medical device using a reduced search space

A method of registering a medical instrument to stored images of a patient anatomy, the method comprising:

• identifying, by a processor, connected anatomical structures in stored images of interior structures of the patient anatomy;
• generating, by the processor, a first three-dimensional model of anatomic passageways included in the connected anatomical structures, the first three-dimensional model including a set of anatomical centerlines of the anatomic passageways;
• generating, by the processor, a second three-dimensional model of the anatomic passageways, the second three-dimensional model including a plurality of linkage elements with each linkage element including two base points disposed on a first anatomical centerline of the set of anatomical centerlines, the two base points defining a linkage element centerline spanning a shortest distance between the two base points;
• receiving tracking data from a tracking system, the tracking data corresponding to a point on the medical instrument while positioned within the connected anatomical structures, the medical instrument being sized for insertion within the connected anatomical structures;
• matching, by the processor, the point on the medical instrument to one of the plurality of linkage elements representing one of the connected anatomical structures to locate the medical instrument relative to the connected anatomical structures in the stored images of the patient anatomy, wherein the matching includes:
• determining, from the second three-dimensional model, a subset of the plurality of linkage elements closer to the point on the medical instrument than each linkage element in a remainder of the plurality of linkage elements based on a plurality of vectors between the point on the medical instrument and one of the two base points of each of the plurality of linkage elements;
• and
• for each linkage element of the subset, determining a distance between the point on the medical instrument and the respective anatomical centerline extending through the linkage element;
• and
• updating the matching of the point on the medical instrument to one of the plurality of linkage elements as the medical instrument is moved within the anatomic passageways.