PT  - JOURNAL ARTICLE
AU  - Qingwei Fang
AU  - Chakameh Z. Jafari
AU  - Shaun Engelmann
AU  - Alankrit Tomar
AU  - Andrew K. Dunn
TI  - Interpreting Inverse Correlation Time: from Blood flow to Vascular Network
AID  - 10.1101/2022.07.15.500238
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.07.15.500238
4099  - http://biorxiv.org/content/early/2022/11/22/2022.07.15.500238.short
4100  - http://biorxiv.org/content/early/2022/11/22/2022.07.15.500238.full
AB  - The inverse correlation time (ICT) is a key quantity in laser speckle contrast imaging (LSCI) measurements. Traditionally, ICT is regarded as a metric of blood flow, such as speed or perfusion. However, we highlight that ICT not only contains important information about blood flow, but also reflects the underlying structure of the vascular network. In the past, ICT has been found to be correlated with vessel diameter. Here, we further report that ICT exhibits a different sensitivity to blood flow depending on vessel orientation. Specifically, ICT is more sensitive to blood flow speed changes in vessels descending from or arising to the tissue surface, compared with those laying parallel to the surface. Those findings shift our understanding of ICT from purely blood flow to a combination of blood flow and vascular network structure. We also develop theories to facilitate the study of vascular network’s impact on ICT.Competing Interest StatementThe authors have declared no competing interest.