Optical Methods for Data Processing in Heat and Fluid Flow

6

Digital Speckle Photography Applied to in Vivo Blood Micro-circulation Monitoring

N Fomin, C Fuentes, J-B Saulnier, and J-L Tuhault

Synopsis

This Chapter deals with blood micro-circulation monitoring using CCD recording of the sequences of the dynamic bio-speckle patterns produced when a tissue under study is illuminated by a laser beam with subsequent cross-correlation analysis of these patterns. The time-space cross-correlation analysis of the temporal evaluation of bio-speckle patterns is shown to be a means of tissue blood micro-circulation monitoring. Digital processing of bio-speckle patterns records yields two-dimensional maps exhibiting the blood flow's temporal and spatial variations. This might be used for bio-medical diagnostic purposes for detecting, for example, microscale deviation from the normal case.

6.1 Introduction

A map of the blood micro-circulation activity in living tissues is of considerable importance for many diagnostic purposes. The skin micro-circulation fulfils the function of thermal and biochemical exchanges and is important, for example, from the point of view of thermal regulation of the body (1). Optical monitoring of the blood flux has an obvious advantage due to its non-intrusive character. Various methods have been studied for measuring this blood micro-circulation by analysis of the light scattered from moving blood using such optical phenomena as the Doppler effect and the dynamic behavior of laser speckles (2). The application of these ...