Dual-fiber laser doppler velocimeter and its application to the measurements of coronary blood velocity

Issue title: 25th Anniversary Volume. Perspectives in Biorheology II. Festschrift for Syoten Oka

Guest editors: Eiichi Fukada and Takehiko Azuma

Article type: Research Article

Authors: Kajiya, F. | Hiramatsu, O. | Ogasawara, Y. | Mito, K. | Tsujioka, K.

Affiliations: Dept. of Medical Engineering and Systems Cardiology, Kawasaki Medical School, Matsushima 577, Kurashiki, 701-01, Japan

Abstract: To obtain a smaller sample volume and a suitable sample position for the measurement of blood velocity, we fabricated a laser Doppler velocimeter (LDV) with a dual-fiber pickup. The two fibers (clad: 62.5 μm and core: 50 μm) were placed side by side. An He-Ne laser was introduced into the blood through one fiber and the backscattered light was collected by the other fiber. The Doppler signal was analyzed by a spectrum analyzer. The spectrum of the Doppler shift frequency showed a sharp peaked pattern for both forward and reverse flows and exhibited an excellent correlation with the known blood velocity. The blood velocity in the poststenotic portion of canine coronary artery was successfully measured by the dual-fiber LDV. These results indicate that the dual-fiber LDV is useful for measuring blood velocity accurately with a small sample volume even in disturbed flow fields.

Keywords: dual-optical fiber, laser Doppler velocimeter, coronary blood velocity, coronary artery stenosis, flow disturbance

DOI: 10.3233/BIR-1988-251-231

Journal: Biorheology, vol. 25, no. 1-2, pp. 227-235, 1988