In vivo dynamic light scattering microscopy of tumour blood vessels

Abstract

Summary We present a study investigating the use of dynamic light scattering microscopy based on the temporal laser speckle's contrast that is produced over time by red blood cells (RBCs) flowing inside tumour blood vessels. The proposed noninvasive methodology is capable of producing high‐resolution images of tumour vasculature. The technique is effective at producing images from tissue at a significant depth, as well as potentially having the ability to monitor tumour perfusion. An advantage of this methodology is that it has improved depth penetration compared with conventional imaging techniques (such as reflected‐light microscopy), and one can avoid the use of any fluorescent or artificial chemicals for labeling. This is advantageous since labeling materials can affect imaging and animal welfare with respect to experiments that require continuous and repetitive monitoring.

Transcranial optical vascular imaging (TOVI) of cortical hemodynamics in mouse brain

“…Laser speckle imaging (LS), also known as laser speckle contrast imaging8, is widely used to visualize the vasculature, blood flow and perfusion in various biomedical applications910, including transcranial imaging of major brain vessels11. LS, which is based on dynamic scattering of diffusively reflected laser light, is sensitive to the movement of red blood cells inside vessels and can therefore be applied for continuous imaging of blood flow dynamics.…”

Multiexposure laser speckle contrast imaging of the angiogenic microenvironment

“…Although LSCI with a temporal processing scheme for contrast calculation can distinguish microvessels, 13 the vessel contrast can only be improved at the expense of sensitivity to blood flow. Although LSCI has previously been used to image angiogenic events in tumors 3 and wounds, 14 no study has demonstrated or achieved robust flow measurements at a high spatial resolution, as may enable reliable longitudinal assessment of angiogenesis using LSCI. We hypothesized that acquiring and combining LSCI data at multiple exposure times will serve the dual purpose of making blood-flow estimates more robust, as well as improving the CNR over a wide range of physiological blood flows, thus enabling sequential monitoring of the angiogenic microenvironment.…”

“…Laser speckle contrast (LSC) imaging (LSCI) is a wide field blood-flow imaging technique that is gaining popularity in neuroscience research, 1, 2 imaging skin tumors, 3 and the retinal vasculature. 4 LSCI has traditionally been used to study shortterm (hours) blood-flow changes in animal models of cerebrovascular reactivity.…”

Multi-modal optical diagnostic approach for non-invasive imaging of blood and lymphatic vascular networks in vivo

“…The fluorescent light is passing through the set of microscope lens, dichroic mirror and emission band-pass filter 510 − 550 nm, and finally detected by same CCD camera. The analysis of acquired images has been performed by using custom made plug-in 18 for ImageJ (Wayne Rasband, NIH) public domain image processing software.…”