Recent advancements in miniaturization of ultrasound technology has enabled the commercialization of catheters including phased array ultrasound imaging transducers small enough to be positioned within a patient's body via intravenous cannulation. By imaging vessels and organs, including the heart, from the inside, such miniature ultrasound transducers have enabled physicians to obtain diagnostic images available by no other means.
The diameter of catheters, particularly intracardiac catheters, are necessarily restricted to about 10 French or smaller by the diameter and profile of blood vessels through which the catheter may be advanced. Consequently, catheter-born ultrasound transducers have been restricted to single transducer elements (providing only distance information) and linear phased-array transducer assemblies which provide a two-dimensional image.