Abstract

Functional performance of handheld laser speckle contrast imaging (LSCI) is compromised by movement artefacts. Here we quantify the movements of a handheld LSCI system employing electromagnetic (EM) tracking and measure the applied translational, tilt and on-surface laser beam speeds. By observing speckle contrast on static objects, the magnitudes of translation and tilt of wavefronts are explored for various scattering levels of the objects. We conclude that for tissue mimicking static phantoms, on-surface speeds play a dominant role to wavefront tilt speed in creation of movement artefacts. The ratio depends on the optical properties of the phantom. Furthermore, with the same applied speed, the drop in the speckle contrast increases with decreasing reduced scattering coefficient, and hence the related movement artefact increases.

© 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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References

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  1. D. A. Boas and A. K. Dunn, “Laser speckle contrast imaging in biomedical optics,” J. Biomed. Opt. 15(1), 011109 (2010).
    [Crossref]
  2. W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
    [Crossref]
  3. D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).
  4. D. Jakovels, I. Saknite, and J. Spigulis, “Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow,” in Biophotonics: Photonic Solutions for Better Health Care IV, J. Popp, V. V. Tuchin, D. L. Matthews, F. S. Pavone, and P. Garside, eds. (SPIE, 2014).
  5. A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
    [Crossref]
  6. A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.
  7. I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
    [Crossref]
  8. R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
    [Crossref]
  9. G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
    [Crossref]
  10. G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
    [Crossref]
  11. L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
    [Crossref]
  12. B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
    [Crossref]
  13. B. Lertsakdadet, C. Dunn, A. Bahani, C. Crouzet, and B. Choi, “Handheld motion stabilized laser speckle imaging,” Biomed. Opt. Express 10(10), 5149 (2019).
    [Crossref]
  14. S. J. Kirkpatrick, D. D. Duncan, and E. M. Wells-Gray, “Detrimental effects of speckle-pixel size matching in laser speckle contrast imaging,” Opt. Lett. 33(24), 2886 (2008).
    [Crossref]
  15. Aurora, “Electromagnetic tracking system specifications,” Tech. rep., NDI (2013).
  16. J. W. Goodman, Speckle Phenomena in Optics: Theory and Applications (Roberts and Company Publishers, 2007).
  17. Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).
  18. R. Michels, F. Foschum, and A. Kienle, “Optical properties of fat emulsions,” Opt. Express 16(8), 5907 (2008).
    [Crossref]
  19. T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
    [Crossref]
  20. L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
    [Crossref]
  21. S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
    [Crossref]
  22. J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
    [Crossref]
  23. S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
    [Crossref]
  24. J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
    [Crossref]

2019 (3)

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

B. Lertsakdadet, C. Dunn, A. Bahani, C. Crouzet, and B. Choi, “Handheld motion stabilized laser speckle imaging,” Biomed. Opt. Express 10(10), 5149 (2019).
[Crossref]

2018 (2)

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

2017 (3)

S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
[Crossref]

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

2016 (1)

R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
[Crossref]

2015 (1)

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

2014 (1)

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

2013 (1)

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

2012 (1)

T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
[Crossref]

2011 (1)

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

2010 (1)

D. A. Boas and A. K. Dunn, “Laser speckle contrast imaging in biomedical optics,” J. Biomed. Opt. 15(1), 011109 (2010).
[Crossref]

2008 (2)

1974 (1)

J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
[Crossref]

Abbiss, J.

J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
[Crossref]

Abraham, P.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Bahadori, S.

S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
[Crossref]

Bahani, A.

Bernal, N.

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Bilenca, A.

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

Blum, K.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Boas, D. A.

D. A. Boas and A. K. Dunn, “Laser speckle contrast imaging in biomedical optics,” J. Biomed. Opt. 15(1), 011109 (2010).
[Crossref]

Boerma, E. C.

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

Bricq, S.

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Brooke, M. J.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.

Bruneau, A.

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

Chappell, P. H.

T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
[Crossref]

Choi, B.

B. Lertsakdadet, C. Dunn, A. Bahani, C. Crouzet, and B. Choi, “Handheld motion stabilized laser speckle imaging,” Biomed. Opt. Express 10(10), 5149 (2019).
[Crossref]

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
[Crossref]

Chubb, T.

J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
[Crossref]

Crouzet, C.

B. Lertsakdadet, C. Dunn, A. Bahani, C. Crouzet, and B. Choi, “Handheld motion stabilized laser speckle imaging,” Biomed. Opt. Express 10(10), 5149 (2019).
[Crossref]

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Cunningham, S. I.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Duncan, D. D.

Dunn, A. K.

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

D. A. Boas and A. K. Dunn, “Laser speckle contrast imaging in biomedical optics,” J. Biomed. Opt. 15(1), 011109 (2010).
[Crossref]

Dunn, C.

Dunn, C. E.

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Durand, S.

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Durkin, A. J.

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Farnebo, S.

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Farraro, R.

R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
[Crossref]

Fathi, O.

R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
[Crossref]

Faucheur, A. L.

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

Fong, Y.

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Foschum, F.

Fox, D. J.

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

Ghatak, S.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Giulianotti, P. C.

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Gnyawali, S. C.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Golightly, L. M.

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

Goodman, J. W.

J. W. Goodman, Speckle Phenomena in Optics: Theory and Applications (Roberts and Company Publishers, 2007).

Heeman, W.

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

Henrion, D.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

Horsten, S.

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Humeau-Heurtier, A.

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

Humeau-Heutier, A.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

Immins, T.

S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
[Crossref]

Jakovels, D.

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

D. Jakovels, I. Saknite, and J. Spigulis, “Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow,” in Biophotonics: Photonic Solutions for Better Health Care IV, J. Popp, V. V. Tuchin, D. L. Matthews, F. S. Pavone, and P. Garside, eds. (SPIE, 2014).

Kalarn, S.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Khanna, S.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Kienle, A.

Kirkpatrick, S. J.

Koerkamp, B. G.

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Krievina, G.

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

Leftheriotis, G.

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Lertsakdadet, B.

B. Lertsakdadet, C. Dunn, A. Bahani, C. Crouzet, and B. Choi, “Handheld motion stabilized laser speckle imaging,” Biomed. Opt. Express 10(10), 5149 (2019).
[Crossref]

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Lewis, J.

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Lister, T.

T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
[Crossref]

Liu, Y.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.

Mahé, G.

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Martin, L.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

Michels, R.

Mirdell, R.

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Murari, K.

A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.

Omarjee, L.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

Pal, D.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Pierre-Destine, L. F.

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

Pike, E.

J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
[Crossref]

Ponticorvo, A.

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Raje, K.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Rege, A.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.

Reiner, T.

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Remer, I.

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

Richards, L. M.

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

Rousseau, P.

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Roy, S.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Saeedi, O. J.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Saknite, I.

D. Jakovels, I. Saknite, and J. Spigulis, “Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow,” in Biophotonics: Photonic Solutions for Better Health Care IV, J. Popp, V. V. Tuchin, D. L. Matthews, F. S. Pavone, and P. Garside, eds. (SPIE, 2014).

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

Schocket, L.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Scott, S.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Sen, C. K.

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Shafi, A.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Signolet, I.

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

Spigulis, J.

D. Jakovels, I. Saknite, and J. Spigulis, “Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow,” in Biophotonics: Photonic Solutions for Better Health Care IV, J. Popp, V. V. Tuchin, D. L. Matthews, F. S. Pavone, and P. Garside, eds. (SPIE, 2014).

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

Steenbergen, W.

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

Tay, D.

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

Tesselaar, E.

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Toledo, L.

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Towle, E. L.

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

van Dam, G. M.

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

Wainwright, T. W.

S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
[Crossref]

Wells-Gray, E. M.

Wright, P. A.

T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
[Crossref]

Yang, B. Y.

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

Zaharans, J.

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

Zotterman, J.

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Biomed. Opt. Express (1)

J. Biomed. Opt. (5)

D. A. Boas and A. K. Dunn, “Laser speckle contrast imaging in biomedical optics,” J. Biomed. Opt. 15(1), 011109 (2010).
[Crossref]

W. Heeman, W. Steenbergen, G. M. van Dam, and E. C. Boerma, “Clinical applications of laser speckle contrast imaging: a review,” J. Biomed. Opt. 24(08), 1 (2019).
[Crossref]

R. Farraro, O. Fathi, and B. Choi, “Handheld, point-of-care laser speckle imaging,” J. Biomed. Opt. 21(9), 094001 (2016).
[Crossref]

B. Lertsakdadet, B. Y. Yang, C. E. Dunn, A. Ponticorvo, C. Crouzet, N. Bernal, A. J. Durkin, and B. Choi, “Correcting for motion artefact in handheld laser speckle images,” J. Biomed. Opt. 23(3), 036006 (2018).
[Crossref]

T. Lister, P. A. Wright, and P. H. Chappell, “Optical properties of human skin,” J. Biomed. Opt. 17(9), 0909011 (2012).
[Crossref]

J. Biophotonics (1)

I. Remer, L. F. Pierre-Destine, D. Tay, L. M. Golightly, and A. Bilenca, “In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging,” J. Biophotonics 12(1), e201800098 (2019).
[Crossref]

J. Visualized Exp. (1)

S. Bahadori, T. Immins, and T. W. Wainwright, “A novel approach to overcome movement artefact when using a laser speckle contrast imaging system for alternating speeds of blood microcirculation,” J. Visualized Exp. 1(126), 56415 (2017).
[Crossref]

Microvasc. Res. (2)

L. Omarjee, I. Signolet, A. Humeau-Heutier, L. Martin, D. Henrion, and P. Abraham, “Optimisation of movement detection and artefact removal during laser speckle contrast imaging,” Microvasc. Res. 97, 75–80 (2015).
[Crossref]

G. Mahé, P. Rousseau, S. Durand, S. Bricq, G. Leftheriotis, and P. Abraham, “Laser speckle contrast imaging accurately measures blood flow over moving skin surfaces,” Microvasc. Res. 81(2), 183–188 (2011).
[Crossref]

Neurophotonics (1)

L. M. Richards, E. L. Towle, D. J. Fox, and A. K. Dunn, “Intraoperative laser speckle contrast imaging with retrospective motion correction for quantitative assessment of cerebral blood flow,” Neurophotonics 1(1), 015006 (2014).
[Crossref]

Opt. Express (1)

Opt. Laser Technol. (1)

J. Abbiss, T. Chubb, and E. Pike, “Laser doppler anemometry,” Opt. Laser Technol. 6(6), 249–261 (1974).
[Crossref]

Opt. Lett. (1)

Pfluegers Arch. (1)

G. Mahé, P. Abraham, A. L. Faucheur, A. Bruneau, A. Humeau-Heurtier, and S. Durand, “Cutaneous microvascular functional assessment during exercise: a novel approach using laser speckle contrast imaging,” Pfluegers Arch. 465(4), 451–458 (2013).
[Crossref]

PLoS One (1)

J. Zotterman, R. Mirdell, S. Horsten, S. Farnebo, and E. Tesselaar, “Methodological concerns with laser speckle contrast imaging in clinical evaluation of microcirculation,” PLoS One 12(3), e0174703 (2017).
[Crossref]

Sci. Rep. (1)

S. C. Gnyawali, K. Blum, D. Pal, S. Ghatak, S. Khanna, S. Roy, and C. K. Sen, “Retooling laser speckle contrast analysis algorithm to enhance non-invasive high resolution laser speckle functional imaging of cutaneous microcirculation,” Sci. Rep. 7(1), 41048 (2017).
[Crossref]

Trans. Vis. Sci. Tech. (1)

A. Rege, S. I. Cunningham, Y. Liu, K. Raje, S. Kalarn, M. J. Brooke, L. Schocket, S. Scott, A. Shafi, L. Toledo, and O. J. Saeedi, “Noninvasive assessment of retinal blood flow using a novel handheld laser speckle contrast imager,” Trans. Vis. Sci. Tech. 7(6), 7 (2018).
[Crossref]

Other (6)

A. Rege, M. J. Brooke, K. Murari, and Y. Liu, “System and method for rapid examination of vasculature and particulate flow using laser speckle contrast imaging,” (2018). US Patent App. 15/767,057.

D. Jakovels, I. Saknite, G. Krievina, J. Zaharans, and J. Spigulis, “Mobile phone based laser speckle contrast imager for assessment of skin blood flow,” in Eighth International Conference on Advanced Optical Materials and Devices (AOMD-8), J. Spigulis, ed. (SPIE, 2014).

D. Jakovels, I. Saknite, and J. Spigulis, “Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow,” in Biophotonics: Photonic Solutions for Better Health Care IV, J. Popp, V. V. Tuchin, D. L. Matthews, F. S. Pavone, and P. Garside, eds. (SPIE, 2014).

Aurora, “Electromagnetic tracking system specifications,” Tech. rep., NDI (2013).

J. W. Goodman, Speckle Phenomena in Optics: Theory and Applications (Roberts and Company Publishers, 2007).

Y. Fong, P. C. Giulianotti, J. Lewis, B. G. Koerkamp, and T. Reiner, Imaging and Visualization in the Modern Operating Room, vol. 112 (Springer, 2015).

Supplementary Material (8)

NameDescription
» Visualization 1       Motorized translation of LSCI system facing on a static matte surface. Speckle frames are shown as speed increases. A progressive profile of spatial speckle contrast versus applied speed is also illustrated.
» Visualization 2       Motorized translation of LSCI system facing on a Delrin plate. Speckle frames are shown as speed increases. A progressive profile of spatial speckle contrast versus applied speed is also illustrated.
» Visualization 3       Motorized translation of LSCI system facing on a static phantom of reduced scattering coefficient of 1 1/mm. Speckle frames are shown as speed increases. A progressive profile of spatial speckle contrast versus applied speed is also illustrated.
» Visualization 4       Realization of tilt of wavefronts on a static matte surface by rotating the object. Speckle frames are shown as rotational speed increases. A progressive profile of spatial speckle contrast versus applied tilt speed is also illustrated.
» Visualization 5       Realization of tilt of wavefronts on a Delrin plate by rotating the object. Speckle frames are shown as rotational speed increases. A progressive profile of spatial speckle contrast versus applied tilt speed is also illustrated.
» Visualization 6       Realization of tilt of wavefronts on a static phantom of reduced scattering coefficient of 1 1/mm by rotating the object. Speckle frames are shown as rotational speed increases. A progressive profile of spatial speckle contrast versus applied tilt sp
» Visualization 7       Progressive demonstration of handheld measurement with laser speckle contrast imaging system. The on-surface beam speed the plotted versus time as well as on xy plane. The associated speckle contrast is demonstrated versus time and also versus the ab
» Visualization 8       Measurement of movements of handheld LSCI using EM-tracker and recording the speckle contrast on a Delrin plate.

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Figures (7)

Fig. 1.
Fig. 1. Experimental setup. (a) Handheld LSCI system. (b) Handheld LSCI measurement and positioning. 1: optical fiber; 2: monochromatic camera; 3: color camera; 4: engineered diffuser; 5 and 6: camera objectives; 7: bandpass filter and linear polarizer; 8: panel and grip; 9: handheld LSCI system including the EM-tracker positioning sensor; 10: table-field generator EM-tracker; 11: Delrin plate.
Fig. 2.
Fig. 2. Mapping three-dimensional (3D) movements of probe to the laser beam displacement on the surface. Schematic diagram of data analysis for six degrees of freedom motion sensor has been shown. (a) 3D coordination system defined as a set of translational and rotational vectors. Solid arrows: translational vectors; dashed curved arrows: rotational vectors; $t_x$: surge; $t_y$: sway; $t_z$: heave; $r_x$: roll; $r_y$: pitch; $r_z$: yaw. Movement of positioning probe during two consecutive data points ($P_1$ and $P_2$) and the corresponding displacement of laser beam on $x$-direction (b) and $y$-direction (c). The pair of ($\Delta T_x$, $\Delta T_y$) indicates the total displacement on the $xy$ plane.
Fig. 3.
Fig. 3. Dependence of speckle contrast on the applied translations and tilts for various levels of scattering. (a) Speckle contrast vs. applied translational speeds. (b) Speckle contrast vs. applied tilt speeds. $\mu '_s$: reduced scattering coefficient. Solid curves: second order exponential fit functions.
Fig. 4.
Fig. 4. Analysis of movement and speed of handheld LSCI system. Representative data of a handheld operation is shown. (a) Lissajous plot indicating the locations of the light beam on a scattering surface. Red circle: baseline measurement while the system is mounted; Red arrow: the episode during which the system is lifted; Black square: the effective handheld measurement. (b) Temporal fluctuations of on-surface locations. (c) Absolute Fourier transform of on-surface locations. Signal: effective handheld measurement; Noise: baseline measurement. (d) Lissajous plot of rotations along $x$ and $y$ axes shown as $\theta$ and $\phi$, respectively. (e) Temporal fluctuations of tilt angle. (f) Absolute Fourier transform of tilt angle. Temporal profiles of absolute on-surface and tilt speeds. $v$: on-surface speed; $\dot \gamma$: tilt speed. (i) Observed speckle contrast on a Delrin plate as a function of on-surface and tilt speeds. $C$: spatial speckle contrast. (g) and (h) are still images of Visualization 7. (i) is still image of Visualization 8.
Fig. 5.
Fig. 5. Overview of averaged speeds estimated from handheld measurements per test subject representing the translational, tilt and on-surface speeds of the light beam. Data are mean$\pm$standard deviation.
Fig. 6.
Fig. 6. In-vivo measurements of speckle contrast. (a) Temporal fluctuation of speckle contrast driven by heartbeat pattern. Red open circles indicate manually chosen sudden drops. During the first ${\rm 4}.8~s$, the LSCI system is still. The vertical dashed line indicates the moment the system starts to move. (b-c) Speckle contrast vs translational speeds for test subjects 1 and 2, respectively. ‘Normal’ refers to the skin area with normal perfusion level. ‘Midalgan’ refers to same skin area after 15 minutes application of Midalgan. Solid curves in (b-c): second order exponential fit functions.
Fig. 7.
Fig. 7. Schematic diagram of wave vectors in a reflection geometry. (a) Translational displacement. (b) Object rotation. $1$: Diffuse distribution of light eventually imaged in a single point on the image plane, for medium of higher scattering level; $2$: Idem, medium of lower scattering level; $\vec {k_{i_1}}$ and $\vec {k_{i_2}}$ illustrate wave vectors of incoming beams in $1$ and $2$, respectively. $\vec {k_s}$: wave vectors of light to be imaged on a single point of the image plane. The curved solid lines in the fluence distributions show random photon paths. The dashed arrows show the movement directions.

Tables (1)

Tables Icon

Table 1. Contribution of translation and tilt of wavefronts in speckle contrast drop for various static phantoms. μ s , reduced scattering coefficient; % Δ C x , speckle contrast drop percentage; on-surf., on-surface speed; tilt., tilt speed.

Equations (8)

Equations on this page are rendered with MathJax. Learn more.

C = σ s I s ¯ ,
{ Δ x ϕ 1 = | z 1 | tan ϕ 1 Δ x ϕ 2 = | z 2 | tan ϕ 2 ,
Δ T x = x 2 + Δ x ϕ 2 ( x 1 + Δ x ϕ 1 ) .
{ Δ y θ 1 = | z 1 | tan θ 1 Δ y θ 2 = | z 2 | tan θ 2 ,
Δ T y = y 2 Δ y θ 2 ( y 1 Δ y θ 1 ) .
( x 2 x 1 ) 2 + ( y 2 y 1 ) 2 Δ t .
γ = tan 1 tan 2 θ + tan 2 ϕ .
ω = v . ( k s k i ) ,

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