Laser speckle contrast imaging

Abstract

Microcirculatory dysfunction often goes unnoticed because there are no apparent symptoms. However, when caused by septicaemia, it will precede macrocirculatory failure and result in early organ dysfunction. This gave rise to research in using laser speckle contrast imaging (LSCI) to evaluate blood flow and perfusion non-invasively.This project aims to study and understand the relationship between perfusion and speckle visibility as well as velocity distribution of blood flow at a certain camera exposure time. Speckle visibility is defined as the ratio between intensity standard deviation and average obtained from moving window method. Ex-vivo experiment was conducted using flow phantom and generation of different flow velocities using a motor pump. In-vivo experiment was performed on examination of speckle visibility on the lower arm during normal condition and blood occlusion period through cuffing of the upper arm.