1. A system for ultrasound (US) interrogation comprising: a memory storing a three dimensional (3D) model of a luminal network and a pathway plan for navigating a luminal network; an electromagnetic (EM) board configured to generate an EM field; an extended working channel (EWC) configured to navigate the luminal network toward a target in accordance with a pathway plan; an EM sensor extending distally from a distal end of the EWC and configured to sense the EM field; a US transducer configured to generate US waves and receive US waves reflected from the luminal network; and a processor configured to process the sensed EM field to synchronize a location of the EM sensor in the 3D model, to process the reflected US waves to generate US images, or to integrate the generated images with the 3D model.