A method and system for imaging, diagnosing, and/or treating an area of interest in a patient's body is provided. More particularly, a manually steered “rapid exchange” type catheter for a system for imaging, diagnosing, and/or treating an area of interest in a patient's body is provided. The catheter comprises a catheter body configured to be introduced to an area of interest in a patient's body, a device for imaging, diagnosing, and/or treating the area of interest contained within the catheter body, and a manual steering device attached to the imaging, diagnosing, and/or treating device to allow an operator to manually steer the imaging, diagnosing, and/or treating device, wherein the catheter is configured to be mounted on a commercially available guidewire.
