Abstract
Improved Laser Speckle Contrast Imaging (LSCI) blood flow analyses that incorporate inverse models of the underlying laser-tissue interaction have been used to develop more quantitative implementations of speckle flowmetry such as Multi-Exposure Speckle Imaging (MESI). In this paper, we determine the optimal camera exposure durations required for obtaining flow information with comparable accuracy with the prevailing MESI implementation utilized in recent in vivo rodent studies. A looping leave-one-out (LOO) algorithm was used to identify exposure subsets which were analyzed for accuracy against flows obtained from analysis with the original full exposure set over 9 animals comprising n = 314 regional flow measurements. From the 15 original exposures, 6 exposures were found using the LOO process to provide comparable accuracy, defined as being no more than 10% deviant, with the original flow measurements. The optimal subset of exposures provides a basis set of camera durations for speckle flowmetry studies of the microcirculation and confers a two-fold faster acquisition rate and a 28% reduction in processing time without sacrificing accuracy. Additionally, the optimization process can be used to identify further reductions in the exposure subsets for tailoring imaging over less expansive flow distributions to enable even faster imaging.
Highlights
Laser speckle contrast imaging (LSCI) is rapidly being adopted by circulation studies for functional information from microvascular beds in exposed or optically accessed tissues
Overall, the optimal set of 6 exposures comprise those presented in Fig. 9 given by the lowest computational complexity while retaining an approximate deviation of 4.2 ± 3.5% with the flow indices computed from all 15 exposures, which more than doubles the measurement acquisition rate
This deviation is within the cross-modality accuracy or uncertainty of the Multi-Exposure Speckle Imaging (MESI) flow dynamics with all 15 exposures against RBC tracking, which can be treated as a calibration or gold standard
Summary
Laser speckle contrast imaging (LSCI) is rapidly being adopted by circulation studies for functional information from microvascular beds in exposed or optically accessed tissues. Given technical and inversemodeling improvements the technique has increased its quantitative accuracy in observing functional hemodynamics beyond just qualitative angiography. An extension to LSCI, called Multi Exposure Speckle Imaging (MESI), further improves the quantitative accuracy of blood flow changes by enabling better separation of non-flow related contributions to the measured speckle contrast [6,7]. The MESI technique uses an improved mathematical model and instrumentation to more precisely extract the flow related contributions. Beyond bench-side physiological research, there are direct implications for prognostic, diagnostic, and intraoperative imaging applications, as speckle imaging of microcirculatory flows is increasingly becoming applied for gauging local and systemic tissue health [8,9]. Laser speckle flowmetry studies are expanding in dermatological [10,11,12,13,14], ophthalmological [15,16,17], and neurosurgical settings [18,19,20]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
