Diffuse Speckle Contrast Analysis (DSCA) for Deep Tissue Blood Flow Monitoring

Abstract

Assessing blood ow, as well as blood volume and oxygen saturation, is of utmost importance for health monitoring. Assessing microcirculation, as opposed to macrocirculation, is especially important for assessing the local tissue viability. Many optics-based modalities have been developed recently such as laser speckle contrast imaging (LSCI), laser Doppler owmetry (LDF), diffuse correlation spectroscopy (DCS), and diffuse speckle contrast analysis (DSCA), which all share the advantage of non-invasive measurement of blood ow using non-ionizing radiation. This paper offers a review of these modalities centered around DSCA, which was developed most recently and is considered one of the fastest and most affordable deep tissue perfusion probes.

Non-Invasive Continuous Optical Monitoring of Cerebral Blood Flow after Traumatic Brain Injury in Mice Using Fiber Camera-Based Speckle Contrast Optical Spectroscopy

“…The movement of these particles causes changes in optical power and speckle pattern blurring, which can be used to estimate blood flow through speckle contrast 𝐾 𝑠 . The relationship between contrast and flow depends on the scattering framework, particle motion, and the presence of static scattering with the relationship of 1/𝐾 𝑠 2 = BFI [19][20][21][22][23][24][25][26][27][28][29], where BFI is the blood flow index, which can be described as an estimation of perfusion, according to the speckle contrast optical spectroscopy theory. This method is easy to use and allows for real-time data processing, which is why it is widely used in many SCOS applications.…”

“…We used fiber camera-based speckle contrast optical spectroscopy (SCOS) [19][20][21][22][23][24][25][26][27][28][29] to measure blood flow in deep tissue. The standard technology for this is continuous wave diffuse correlation spectroscopy (DCS), which has limitations in terms of cost, speed, and the number of detectors that can be used.…”

Recent Advances in Biomedical Photonic Sensors: A Focus on Optical-Fibre-Based Sensing

“…It is a simple and powerful method for 2D mapping of flow and vibration [ 16 ]. Indeed, extensive research has been performed on monitoring microvascular blood flow utilizing speckle imaging techniques [ 49 , 50 ]. Regarding optical fibres and laser-speckle techniques, Rodríguez-Cuevas et al presented a noncontact, continuous, patient monitoring using fibre speckelgram sensors based on polymer optical fibres [ 51 ].…”

Handheld versus mounted laser speckle contrast perfusion imaging demonstrated in psoriasis lesions

“…The microcirculation in the skin is responsible for delivering oxygen and nutrients to the tissue and evaluation of the microvasculature provides insights regarding tissue viability and health. Microcirculatory perfusion imaging has the potential to provide valuable information on the microvasculature and has gained attention in the past years 1 – 4 . Examples of medical applications of perfusion imaging include psoriasis 5 – 7 , burn wound depth assessment 8 and postoperative monitoring 9 .…”