A dual-mode imaging catheter for intravascular ultrasound application.

Both the morphological anatomy and functional parameters such as flow speed of the artery provide valuable information for the evaluation of cardiovascular diseases. Direct measurement of the arterial wall can be achieved by intravascular optical/ultrasound imaging methods, however no functional data are acquired with these methods. Fractional flow reserve (FFR) and Doppler wire have been used to assess the blood flow information, but do not provide cross-sectional images of the artery. This study is the first to design and fabricate a dual mode imaging catheter that contains a forward-looking ultrasonic transducer and a side-looking ultrasonic transducer together in one catheter. This dual-mode catheter not only provides morphological information about the artery, but also a precise measurement of functional flow. The data indicate that the proposed catheter can be used to acquire multiple parameters of the artery with a one-time procedure. This novel one-catheter approach could be used for the functional diagnosis of atherosclerotic arteries.