In vivo flow speed measurement of capillaries by photoacoustic correlation spectroscopy

Article (PDF Available)inOptics Letters 36(20):4017-9 · October 2011with42 Reads
DOI: 10.1364/OL.36.004017 · Source: PubMed
Abstract
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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    • "The axial andFig. 8. Transit-time principle for particle ensembles69707172. As cells transit the focus with a greater speed, features of the density distribution will show up with sharper peaks.Fig. "
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