A medical system includes a catheter having an elongated tubular member and an inner core slideably received within the elongated member. The inner core includes an imager on a distal end and is coupled with a control system and an imaging system. The inner core is configured to scan the interior of a lumen by radially rotating around a center axis and axially translating along the center axis while within the elongated member. The medical system is configured to dynamically image a body lumen at a high speed in order to allow for optical imaging in a safe manner without long durations of blood sequestration and displacement. The medical system is configured to obtain three dimensional images of the body lumen with as little as one dimensional scanning of the lumen. Images of the lumen can be stored and viewed at a desired rate after scanning.