Dr. Adam Santorelli Profile

Dr. Adam Santorelli

at University of Texas

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

SPIE Journal Paper | 11 March 2023 Open Access

Using pressure-driven flow systems to evaluate laser speckle contrast imaging

Colin T. Sullender, Adam Santorelli, Lisa M. Richards, Pawan K. Mannava, Christopher Smith, Andrew K. Dunn

JBO, Vol. 28, Issue 03, 036003, (March 2023) https://doi.org/10.1117/12.10.1117/1.JBO.28.3.036003

KEYWORDS: Laser speckle contrast imaging, Microfluidics, Sensors, Imaging systems, Laser systems engineering, Equipment, Control systems, Speckle, Cameras, Reproducibility

Read Abstract +

SignificanceMicrofluidic flow phantom studies are commonly used for characterizing the performance of laser speckle contrast imaging (LSCI) instruments. The selection of the flow control system is critical for the reliable generation of flow during testing. The majority of recent LSCI studies using microfluidics used syringe pumps for flow control.AimWe quantified the uncertainty in flow generation for a syringe pump and a pressure-regulated flow system. We then assessed the performance of both LSCI and multi-exposure speckle imaging (MESI) using the pressure-regulated flow system across a range of flow speeds.ApproachThe syringe pump and pressure-regulated flow systems were evaluated during stepped flow profile experiments in a microfluidic device using an inline flow sensor. The uncertainty associated with each flow system was calculated and used to determine the reliability for instrument testing. The pressure-regulated flow system was then used to characterize the relative performance of LSCI and MESI during stepped flow profile experiments while using the inline flow sensor as reference.ResultsThe pressure-regulated flow system produced much more stable and reproducible flow outputs compared to the syringe pump. The expanded uncertainty for the syringe pump was 8 to 20 × higher than that of the pressure-regulated flow system across the tested flow speeds. Using the pressure-regulated flow system, MESI outperformed single-exposure LSCI at all flow speeds and closely mirrored the flow sensor measurements, with average errors of 4.6 % ± 2.6 % and 15.7 % ± 4.6 % , respectively.ConclusionsPressure-regulated flow systems should be used instead of syringe pumps when assessing the performance of flow measurement techniques with microfluidic studies. MESI offers more accurate relative flow measurements than traditional LSCI across a wide range of flow speeds.

DOWNLOAD PAPER

Proceedings Article | 7 March 2023 Presentation + Paper

Impact of logarithmic and linear spaced camera exposure durations for multi-exposure speckle imaging

Adam Santorelli, Christopher Smith, Andrew Dunn

Proceedings Volume 12378, 1237803 (2023) https://doi.org/10.1117/12.2648443

KEYWORDS: Cameras, Speckle, Microfluidics, Laser speckle contrast imaging, Speckle imaging, Imaging systems, Sensors, Time metrology, Dynamic light scattering

Read Abstract +

Neurosurgical interventions benefit greatly from monitoring of cerebral blood flow (CBF). Laser speckle contrast imaging (LSCI) is a label-free optical imaging technique that can provide continuous, high spatiotemporal maps of flow dynamics, allowing clinicians to monitor changes in CBF without any interruption to the surgical workflow. Multi-exposure speckle imaging (MESI) is an extension of LSCI that collects speckle images at numerous camera exposure times to create reproducible and quantifiable measurements of flow, through a more robust calculation of the correlation time constant. This work is focused on investigating whether the chosen spacing of the camera exposure times can impact the resulting computation of the inverse correlation time (ICT). A microfluidic phantom using a pressure-regulated flow control system is used to generate a 5-step and 7-step flow profile. MESI data is collected with three different exposure time spacings; logarithmic-spaced, linear-spaced, and the ad hoc exposure times from previous research. Using a nonlinear least squares fitting algorithm we fit the measured data to solve for the speckle correlation time constant at each MESI frame. We compare the quantified flow, based on the computed ICT for each exposure time collection method. These results suggest that future research and clinical adaptations should consider implementing logarithmic -spaced exposure times for MESI as it may provide more reliable and accurate estimates of flow, as well as faster acquisition times, without the need for specially chosen exposure times.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years