Catheters and methods for removing material from (or “debulking”) a body lumen while imaging the region comprised of the material are provided. The catheters can be used in body lumens, including but not limited to intravascular lumens such as coronary or peripheral arteries. The catheters include housings or other structures to mount or protect an imaging transducer. Generally, debulking catheters include a proximal portion, a distal portion having an opening, a cutting element which may be exposed through the opening to contact material in a body lumen and an imaging transducer with associated circuitry and display. The catheter debulks a body lumen when it is moved while the cutting element is in contact with the material in the lumen and the region comprised of the material is imaged before, after, or during catheter movement.