ABSTRACT
This chapter reviews the various methods used to achieve the registration for the echocardiography imaging modality. X-ray fluoroscopy is a live imaging modality with frame rates of up to 30 frames per second. X-ray fluoroscopy provides excellent visualization of the interventional devices and is used in almost all minimally invasive interventions. X-ray fluoroscopy systems for use during cardiac surgery comprise a rotatable gantry containing an x-ray source and detector on opposite sides of the patient. Cardiac echocardiographic systems are currently available in three varieties depending on the positioning of the ultrasound probe: transthoracic echo (TTE), transesophageal echo (TEE), and intracardiac echo (ICE). Fiducial-based tracking is an image-based registration technique that bypasses the need for physical sensors and x-ray calibration by directly tracking the ultrasound probe in the x-ray images. The key feature of fiducial-based approaches is to add an external attachment to the TEE probe that contains point markers that are easily identified in x-ray.
