In vivo flow speed measurement of capillaries by photoacoustic correlation spectroscopy

Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, USA.
Optics Letters (Impact Factor: 3.29). 10/2011; 36(20):4017-9. DOI: 10.1364/OL.36.004017
Source: PubMed


We recently proposed photoacoustic correlation spectroscopy (PACS) and demonstrated a proof-of-concept experiment. Here we use the technique for in vivo flow speed measurement in capillaries in a chick embryo model. The photoacoustic microscopy system is used to render high spatial resolution and high sensitivity, enabling sufficient signals from single red blood cells. The probe beam size is calibrated by a blood-mimicking phantom. The results indicate the feasibility of using PACS to study flow speeds in capillaries.

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