Intraluminal fiber-optic Doppler imaging catheter for structural and functional optical coherence tomography

Abstract

A miniature fiber Doppler imaging catheter for integrated functional and structural optical coherence tomography (OCT) imaging has been developed. The Doppler catheter can be used to map blood flow profile within a vessel as well as image vessel wall structures. The prototype Doppler catheter was demonstrated in measuring the intraluminal velocity profile in a vessel phantom (conduit). A simple mathematical model can be used to estimate the flow profile outside of normal OCT beam penetration. By extending the spatial range of the flow measurements to approximately two times the normal OCT image penetration depth, the total flow rate can then be calculated from the estimated velocity profiles. The measured total flow rate in the vessel phantom obtained from the Doppler imaging catheter correlates well with the calibrated flow values. The Doppler OCT catheter's ability to simultaneously obtain both structural and functional information makes it a potentially powerful device of cardiovascular imaging.