Abstract

A novel method (Sophia) is presented to track oxygen saturation changes in a controlled environment using an RGB camera placed approximately 1.5 m away from the subject. The method is evaluated on five healthy volunteers (Fitzpatrick skin phenotypes II, III, and IV) whose oxygen saturations were varied between 80% and 100% in a purpose-built chamber over 40 minutes each. The method carefully selects regions of interest (ROI) in the camera image by calculating signal-to-noise ratios for each ROI. This allows it to track changes in oxygen saturation accurately with respect to a conventional pulse oximeter (median coefficient of determination, 0.85).

© 2015 Optical Society of America

Full Article  |  PDF Article

Corrections

23 October 2015: A correction was made to Ref. 24.


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References

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2015 (3)

U. Bal, “Non-contact estimation of heart rate and oxygen saturation using ambient light,” Biomed. Opt. Express 6(10), 86–97 (2015)
[Crossref] [PubMed]

M. Kumar, A. Veeraraghavan, and A. Sabharwal, “DistancePPG: robust non-contact vital signs monitoring using a camera,” Biomed. Opt. Express 6(5) 1488–1565 (2015)
[Crossref] [PubMed]

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

2014 (3)

G. de Haan and A. van Leest, “Improved motion robustness of remote-PPG by using the blood volume pulse signature,” Physiol. Meas. 35(9), 1913–1926 (2014)
[Crossref] [PubMed]

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

2013 (2)

F. Bousefsaf, C. Maaoui, and A. Pruski, “Continuous wavelet filtering on webcam photoplethysmographic signals to remotely assess the instantaneous heart rate,” Biomed. Signal Proces. 8(6), 568–574 (2013)
[Crossref]

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

2012 (1)

Q. J. Milner and G. R. Matthews, “An assessment of the accuracy of pulse oximeters,” Anaesthesia 67(4), 396–401 (2012)
[Crossref] [PubMed]

2011 (1)

B. D. Kent, P. D. Mitchell, and W. T. McNicholas, “Hypoxemia in patients with COPD: cause, effects, and disease progression,” Int. J. Chron. Obstruct. Pulmon. Dis. 6, 199–208 (2011)
[PubMed]

2010 (1)

2008 (3)

2007 (2)

J. W. Severinghaus, “Discovery of pulse oximetry,” Anesth. Analg. 105(6), S1–S4 (2007)
[Crossref]

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1 (2007)
[Crossref] [PubMed]

2005 (1)

F. P. Wieringa, F. Mastik, and A. F. van der Steen, “Contactless multiple wavelength photoplethysmographic imaging: a first step twoard SpO2 camera technology,” Ann. Biomed. Eng. 33(8), 1034–1041 (2005)
[Crossref] [PubMed]

2004 (1)

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

2002 (1)

R. K. Pearson, “Outliers in process modeling and identification,” IEEE Trans. Control Syst. Technol. 10(1), 55–63 (2002)
[Crossref]

2001 (1)

G. Zonios, J. Bykowski, and N. Kollias, “Skin melanin, hemoglobin, and light scattering roperties can be quantitatively assessed in vivo using diffuse reflectance spectroscopy,” J. Invest. Dermatol. 117(6), 1452–1457 (2001)
[Crossref]

1995 (2)

I. Fine and A. Weinreb, “Multiple scattering effect in transmission pulse oximetry,” Med. Biol. Eng. Comput. 33(5), 709–712 (1995)
[Crossref] [PubMed]

C. D. Hanning and J. M. Alexander-Williams, “Pulse Oximetry: A Practical Review,” Brit. Med. J. 311(7001), 367–370 (1995)
[Crossref] [PubMed]

1993 (1)

M. C. Wilkins, “Residual bacterial contamination on reusable pulse oximetry sensors,” Respir. Care 38(11), 1155–1160 (1993)
[PubMed]

1989 (1)

Y. Mendelson and J. C Kent, “Variations in optical absorption spectra of adult and fetal haemoglobins and its effect on pulse oximetry,” IEEE Trans. Biomed. Eng. 36(8), 844–848 (1989)
[Crossref] [PubMed]

1985 (1)

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

1975 (1)

T. B. Fitzpatrick, “Soleil et peau,” J. de Medecine Esthetique 2, 33–34 (1975)

1974 (1)

Aizu, Y.

Alexander-Williams, J. M.

C. D. Hanning and J. M. Alexander-Williams, “Pulse Oximetry: A Practical Review,” Brit. Med. J. 311(7001), 367–370 (1995)
[Crossref] [PubMed]

Allen, J.

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1 (2007)
[Crossref] [PubMed]

Ansermino, J. M.

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

Bal, U.

Balakrishnan, G.

G. Balakrishnan, F. Durand, and J. Guttag, “Detecting pulse from head motions in video,” in Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (IEEE, 2013), pp. 3430–3437

Barson, R. A.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

Benaron, A. D.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Bousefsaf, F.

F. Bousefsaf, C. Maaoui, and A. Pruski, “Continuous wavelet filtering on webcam photoplethysmographic signals to remotely assess the instantaneous heart rate,” Biomed. Signal Proces. 8(6), 568–574 (2013)
[Crossref]

Brock-Utne, J.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Bykowski, J.

G. Zonios, J. Bykowski, and N. Kollias, “Skin melanin, hemoglobin, and light scattering roperties can be quantitatively assessed in vivo using diffuse reflectance spectroscopy,” J. Invest. Dermatol. 117(6), 1452–1457 (2001)
[Crossref]

Cheong, W.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Cissel, M.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Clark, F. L.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Clifton, D. A.

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

Davis, S.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Davison, A.G.

B.R. O’Driscoll, L. S. Howard, and A.G. Davison, “BTS guideline for emergency oxygen use in adult patients,” Thorax 63(6 Suppl.), S1–S68 (2008)

de Haan, G.

G. de Haan and A. van Leest, “Improved motion robustness of remote-PPG by using the blood volume pulse signature,” Physiol. Meas. 35(9), 1913–1926 (2014)
[Crossref] [PubMed]

Dong, Y.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Duckworth, J. L.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Dumont, G.

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

Durand, F.

G. Balakrishnan, F. Durand, and J. Guttag, “Detecting pulse from head motions in video,” in Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (IEEE, 2013), pp. 3430–3437

Feng, Y.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Fincher, E. F.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Fine, I.

I. Fine and A. Weinreb, “Multiple scattering effect in transmission pulse oximetry,” Med. Biol. Eng. Comput. 33(5), 709–712 (1995)
[Crossref] [PubMed]

Fitzpatrick, T. B.

T. B. Fitzpatrick, “Soleil et peau,” J. de Medecine Esthetique 2, 33–34 (1975)

Friedland, S.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Green, G.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Guazzi, A.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

Guttag, J.

G. Balakrishnan, F. Durand, and J. Guttag, “Detecting pulse from head motions in video,” in Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (IEEE, 2013), pp. 3430–3437

Hanning, C. D.

C. D. Hanning and J. M. Alexander-Williams, “Pulse Oximetry: A Practical Review,” Brit. Med. J. 311(7001), 367–370 (1995)
[Crossref] [PubMed]

Howard, L. S.

B.R. O’Driscoll, L. S. Howard, and A.G. Davison, “BTS guideline for emergency oxygen use in adult patients,” Thorax 63(6 Suppl.), S1–S68 (2008)

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

Howse, N. P.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

Hsu, C. P.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Ikonomidou, V. N.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Jian, Y.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Jin, X.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Jorge, J.

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Karlen, W.

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

Kaur, B.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Kent, B. D.

B. D. Kent, P. D. Mitchell, and W. T. McNicholas, “Hypoxemia in patients with COPD: cause, effects, and disease progression,” Int. J. Chron. Obstruct. Pulmon. Dis. 6, 199–208 (2011)
[PubMed]

Kent, J. C

Y. Mendelson and J. C Kent, “Variations in optical absorption spectra of adult and fetal haemoglobins and its effect on pulse oximetry,” IEEE Trans. Biomed. Eng. 36(8), 844–848 (1989)
[Crossref] [PubMed]

Kollias, N.

G. Zonios, J. Bykowski, and N. Kollias, “Skin melanin, hemoglobin, and light scattering roperties can be quantitatively assessed in vivo using diffuse reflectance spectroscopy,” J. Invest. Dermatol. 117(6), 1452–1457 (2001)
[Crossref]

Kong, L.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Kumar, M.

M. Kumar, A. Veeraraghavan, and A. Sabharwal, “DistancePPG: robust non-contact vital signs monitoring using a camera,” Biomed. Opt. Express 6(5) 1488–1565 (2015)
[Crossref] [PubMed]

Li, B.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Lim, J.

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

Liu, M.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Liu, X.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Luthra, M.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Maaoui, C.

F. Bousefsaf, C. Maaoui, and A. Pruski, “Continuous wavelet filtering on webcam photoplethysmographic signals to remotely assess the instantaneous heart rate,” Biomed. Signal Proces. 8(6), 568–574 (2013)
[Crossref]

Maeda, T.

Mastik, F.

F. P. Wieringa, F. Mastik, and A. F. van der Steen, “Contactless multiple wavelength photoplethysmographic imaging: a first step twoard SpO2 camera technology,” Ann. Biomed. Eng. 33(8), 1034–1041 (2005)
[Crossref] [PubMed]

Matthews, G. R.

Q. J. Milner and G. R. Matthews, “An assessment of the accuracy of pulse oximeters,” Anaesthesia 67(4), 396–401 (2012)
[Crossref] [PubMed]

McCormick, K.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

McDuff, D. J.

McGill, T. R.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

McIntyre, M. E.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

McNicholas, W. T.

B. D. Kent, P. D. Mitchell, and W. T. McNicholas, “Hypoxemia in patients with COPD: cause, effects, and disease progression,” Int. J. Chron. Obstruct. Pulmon. Dis. 6, 199–208 (2011)
[PubMed]

Mendelson, Y.

Y. Mendelson and J. C Kent, “Variations in optical absorption spectra of adult and fetal haemoglobins and its effect on pulse oximetry,” IEEE Trans. Biomed. Eng. 36(8), 844–848 (1989)
[Crossref] [PubMed]

Milner, Q. J.

Q. J. Milner and G. R. Matthews, “An assessment of the accuracy of pulse oximeters,” Anaesthesia 67(4), 396–401 (2012)
[Crossref] [PubMed]

Mitchell, P. D.

B. D. Kent, P. D. Mitchell, and W. T. McNicholas, “Hypoxemia in patients with COPD: cause, effects, and disease progression,” Int. J. Chron. Obstruct. Pulmon. Dis. 6, 199–208 (2011)
[PubMed]

Moses, S.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Nelson, J. S.

Nexhat, C.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Niizeki, J.

Nishidate, I.

O’Connor, D. F.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

O’Driscoll, B.R.

B.R. O’Driscoll, L. S. Howard, and A.G. Davison, “BTS guideline for emergency oxygen use in adult patients,” Thorax 63(6 Suppl.), S1–S68 (2008)

Palmer, K. F.

Parachikov, I. H.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Pearson, R. K.

R. K. Pearson, “Outliers in process modeling and identification,” IEEE Trans. Control Syst. Technol. 10(1), 55–63 (2002)
[Crossref]

Picard, R. W.

Poh, M. Z.

Pruski, A.

F. Bousefsaf, C. Maaoui, and A. Pruski, “Continuous wavelet filtering on webcam photoplethysmographic signals to remotely assess the instantaneous heart rate,” Biomed. Signal Proces. 8(6), 568–574 (2013)
[Crossref]

Pugh, C.

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

Robbins., P. A.

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

Sabharwal, A.

M. Kumar, A. Veeraraghavan, and A. Sabharwal, “DistancePPG: robust non-contact vital signs monitoring using a camera,” Biomed. Opt. Express 6(5) 1488–1565 (2015)
[Crossref] [PubMed]

Sasaoka, K.

Scheffer, C.

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

Severinghaus, J. W.

J. W. Severinghaus, “Discovery of pulse oximetry,” Anesth. Analg. 105(6), S1–S4 (2007)
[Crossref]

Shenvi, A.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Soetniko, R.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Stevenson, D. K.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Svaasand, L. O.

Tarassenko, L.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

Tarbox, E.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Terris, M. K.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Tran, N.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Vaidya, M.

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

van der Starre, P. J. A.

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

van der Steen, A. F.

F. P. Wieringa, F. Mastik, and A. F. van der Steen, “Contactless multiple wavelength photoplethysmographic imaging: a first step twoard SpO2 camera technology,” Ann. Biomed. Eng. 33(8), 1034–1041 (2005)
[Crossref] [PubMed]

van Leest, A.

G. de Haan and A. van Leest, “Improved motion robustness of remote-PPG by using the blood volume pulse signature,” Physiol. Meas. 35(9), 1913–1926 (2014)
[Crossref] [PubMed]

Veeraraghavan, A.

M. Kumar, A. Veeraraghavan, and A. Sabharwal, “DistancePPG: robust non-contact vital signs monitoring using a camera,” Biomed. Opt. Express 6(5) 1488–1565 (2015)
[Crossref] [PubMed]

Verkruysse, W.

Villarroel, M.

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Watkinson, P.

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

Webster, J. G.

J. G. Webster, Design of Pulse Oximeters (CRC Press, 1997)
[Crossref]

Weinreb, A.

I. Fine and A. Weinreb, “Multiple scattering effect in transmission pulse oximetry,” Med. Biol. Eng. Comput. 33(5), 709–712 (1995)
[Crossref] [PubMed]

Wieringa, F. P.

F. P. Wieringa, F. Mastik, and A. F. van der Steen, “Contactless multiple wavelength photoplethysmographic imaging: a first step twoard SpO2 camera technology,” Ann. Biomed. Eng. 33(8), 1034–1041 (2005)
[Crossref] [PubMed]

Wilkins, M. C.

M. C. Wilkins, “Residual bacterial contamination on reusable pulse oximetry sensors,” Respir. Care 38(11), 1155–1160 (1993)
[PubMed]

Williams, D.

Wu, H.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Yuasa, T.

Zhao, Y.

L. Kong, Y. Zhao, Y. Dong, Y. Jian, X. Jin, B. Li, Y. Feng, M. Liu, X. Liu, and H. Wu, “Non-contact detection of oxygen saturation based on visible light imaging device using ambient light,” Opt. Express 21(15), 1764–1771 (2013)
[Crossref]

Zonios, G.

G. Zonios, J. Bykowski, and N. Kollias, “Skin melanin, hemoglobin, and light scattering roperties can be quantitatively assessed in vivo using diffuse reflectance spectroscopy,” J. Invest. Dermatol. 117(6), 1452–1457 (2001)
[Crossref]

Anaesthesia (1)

Q. J. Milner and G. R. Matthews, “An assessment of the accuracy of pulse oximeters,” Anaesthesia 67(4), 396–401 (2012)
[Crossref] [PubMed]

Anaesthesiology (1)

A. D. Benaron, I. H. Parachikov, S. Friedland, R. Soetniko, J. Brock-Utne, P. J. A. van der Starre, C. Nexhat, M. K. Terris, E. F. Fincher, C. P. Hsu, F. L. Clark, W. Cheong, J. L. Duckworth, and D. K. Stevenson, “Continuous, noninvasive and localised microvascular tissue oximetry using visible light spectroscopy,” Anaesthesiology 100(6), 1469–1475 (2004)
[Crossref]

Anesth. Analg. (1)

J. W. Severinghaus, “Discovery of pulse oximetry,” Anesth. Analg. 105(6), S1–S4 (2007)
[Crossref]

Ann. Biomed. Eng. (1)

F. P. Wieringa, F. Mastik, and A. F. van der Steen, “Contactless multiple wavelength photoplethysmographic imaging: a first step twoard SpO2 camera technology,” Ann. Biomed. Eng. 33(8), 1034–1041 (2005)
[Crossref] [PubMed]

Biomed. Opt. Express (2)

M. Kumar, A. Veeraraghavan, and A. Sabharwal, “DistancePPG: robust non-contact vital signs monitoring using a camera,” Biomed. Opt. Express 6(5) 1488–1565 (2015)
[Crossref] [PubMed]

U. Bal, “Non-contact estimation of heart rate and oxygen saturation using ambient light,” Biomed. Opt. Express 6(10), 86–97 (2015)
[Crossref] [PubMed]

Biomed. Signal Proces. (1)

F. Bousefsaf, C. Maaoui, and A. Pruski, “Continuous wavelet filtering on webcam photoplethysmographic signals to remotely assess the instantaneous heart rate,” Biomed. Signal Proces. 8(6), 568–574 (2013)
[Crossref]

Brit. Med. J. (1)

C. D. Hanning and J. M. Alexander-Williams, “Pulse Oximetry: A Practical Review,” Brit. Med. J. 311(7001), 367–370 (1995)
[Crossref] [PubMed]

Healthc. Technol. Lett. (1)

M. Villarroel, A. Guazzi, J. Jorge, S. Davis, P. Watkinson, G. Green, A. Shenvi, K. McCormick, and L. Tarassenko, “Continuous non-contact vital sign monitoring in the neonatal intensive care unit,” Healthc. Technol. Lett. 1(3), 87–91 (2014)
[Crossref]

IEEE Trans. Biomed. Eng. (1)

Y. Mendelson and J. C Kent, “Variations in optical absorption spectra of adult and fetal haemoglobins and its effect on pulse oximetry,” IEEE Trans. Biomed. Eng. 36(8), 844–848 (1989)
[Crossref] [PubMed]

IEEE Trans. Control Syst. Technol. (1)

R. K. Pearson, “Outliers in process modeling and identification,” IEEE Trans. Control Syst. Technol. 10(1), 55–63 (2002)
[Crossref]

Int. J. Chron. Obstruct. Pulmon. Dis. (1)

B. D. Kent, P. D. Mitchell, and W. T. McNicholas, “Hypoxemia in patients with COPD: cause, effects, and disease progression,” Int. J. Chron. Obstruct. Pulmon. Dis. 6, 199–208 (2011)
[PubMed]

J. Appl. Physiol. (1)

L. S. Howard, R. A. Barson, N. P. Howse, T. R. McGill, M. E. McIntyre, D. F. O’Connor, and P. A. Robbins., “Chamber for controlling end-tidal gas tensions over sustained periods in humans,” J. Appl. Physiol. 78(3), 1088–1091 (1985)

J. de Medecine Esthetique (1)

T. B. Fitzpatrick, “Soleil et peau,” J. de Medecine Esthetique 2, 33–34 (1975)

J. Invest. Dermatol. (1)

G. Zonios, J. Bykowski, and N. Kollias, “Skin melanin, hemoglobin, and light scattering roperties can be quantitatively assessed in vivo using diffuse reflectance spectroscopy,” J. Invest. Dermatol. 117(6), 1452–1457 (2001)
[Crossref]

J. Opt. Soc. Am. (1)

Med. Biol. Eng. Comput. (1)

I. Fine and A. Weinreb, “Multiple scattering effect in transmission pulse oximetry,” Med. Biol. Eng. Comput. 33(5), 709–712 (1995)
[Crossref] [PubMed]

Opt. Express (3)

Opt. Lett. (1)

Physiol. Meas. (3)

L. Tarassenko, M. Villarroel, A. Guazzi, J. Jorge, D. A. Clifton, and C. Pugh, “Non-contact video-based vital sign monitoring using ambient light and auto-regressive models,” Physiol. Meas. 35(5), 805–831 (2014)
[Crossref]

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1 (2007)
[Crossref] [PubMed]

G. de Haan and A. van Leest, “Improved motion robustness of remote-PPG by using the blood volume pulse signature,” Physiol. Meas. 35(9), 1913–1926 (2014)
[Crossref] [PubMed]

Proc. SPIE (1)

B. Kaur, E. Tarbox, M. Cissel, S. Moses, M. Luthra, M. Vaidya, N. Tran, and V. N. Ikonomidou, “Remotely detected differential pulse transit time as a stress indicator,” Proc. SPIE 9496, 949604 (2015)
[Crossref]

Respir. Care (1)

M. C. Wilkins, “Residual bacterial contamination on reusable pulse oximetry sensors,” Respir. Care 38(11), 1155–1160 (1993)
[PubMed]

Thorax (1)

B.R. O’Driscoll, L. S. Howard, and A.G. Davison, “BTS guideline for emergency oxygen use in adult patients,” Thorax 63(6 Suppl.), S1–S68 (2008)

Other (4)

J. G. Webster, Design of Pulse Oximeters (CRC Press, 1997)
[Crossref]

G. Balakrishnan, F. Durand, and J. Guttag, “Detecting pulse from head motions in video,” in Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (IEEE, 2013), pp. 3430–3437

A. R. Guazzi, “Sophia Dataset,” (2015), 10.5287/bodleian:dr26xx537 .

W. Karlen, J. Lim, J. M. Ansermino, G. Dumont, and C. Scheffer, “Design challenges for camera oximetry on a mobile phone,” in Proceedings of IEEE Engineering in Medicine and Biology Society Annual Conference (IEEE, 2012), pp. 2448–2451

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Figures (7)

Fig. 1
Fig. 1 Schematic illustration of Sophia. Steps that are the same for all ROIs i are drawn in dashed lines. HR = Heart Rate; BR = Breathing Rate; SNR = Signal-to-Noise-Ratio.
Fig. 2
Fig. 2 Bland-Altman plot of all results for oxygen saturation. The estimated oxygen saturations (obtained by fitting a linear model to the data) are compared with the mean reference oxygen saturation. The red line and green lines either side of it show μ±1.96σ = 0.00 ± 5.51.
Fig. 3
Fig. 3 Oxygen saturation results for Subject 3. Top-left: results with the camera using the method described. Bottom-left: reference oxygen saturation from the pulse oximeter. Right Scatter plot showing the relationship between the logarithm of the ratio of ratios using the red and blue channels of the camera and the oxygen saturation from the pulse oximeter.
Fig. 4
Fig. 4 Oxygen saturation results for Subject 4. Top-left: results with the camera using the method described. Bottom-left: reference oxygen saturation from the pulse oximeter. Right Scatter plot showing the relationship between the logarithm of the ratio of ratios using the red and blue channels of the camera and the oxygen saturation from the pulse oximeter.
Fig. 5
Fig. 5 A comparison of different ROI selection methods and of the effect of the inclusion criteria on the ROI selection in Sophia, carried out on all subjects considered. From left to right: the method introduced by [14], using a fixed region manually set onto the lower part of the face; the method introduced by [15], using a fixed region placed on the cheek of the subject; the method introduced by [17], using the entirety of the skin as segmented by a segmentation in YCbCr space; Sophia with none of the thresholds introduced in Equation 13; Sophia using only the heart rate SNR threshold; Sophia using the heart rate and the breathing SNR rate thresholds; Sophia using all thresholds as described in this paper. The line between the points does not indicate any continuity between reported measures: it has been added to aid the reader.
Fig. 6
Fig. 6 Bland-Altman plot of all results for oxygen saturation. The estimated oxygen saturations (obtained by fitting a linear model via the leave-one-out procedure to the data for each subject) are compared to the mean reference oxygen saturation. The red line and green lines either side of it show μ ± 1.96σ = 0.19 ± 5.81.
Fig. 7
Fig. 7 Effect of varying the minimum number of regions of interest on the results for Subject 3. Top: mean absolute error between the reference and camera oxygen saturations for varying the minimum number of ROIs in each window. Middle: effect of varying the minimum number of ROIs on the coefficient of determination. Bottom: percentage of windows rejected as a result of varying the minimum number of ROIs.

Tables (3)

Tables Icon

Table 1 Skin colour type (Fitzpatrick scale I through to VI), and proportion of data used per subject. Both the algorithm (Sophia) and post-processing techniques applied to the results reject data that are detected as noise or outliers.

Tables Icon

Table 2 Oxygen saturation results for the non-contact (Camera) estimates versus the mean of the two reference pulse oximeters (Ref μ ), reported as the gradient between the two, the coefficient of determination, and the mean absolute error (MAE) and the mean error (ME). The MAE and ME between the right reference pulse oximeter (Ref R ) and the left reference pulse oximeter (Ref L ) are also reported, as is the spread of the mean reference data in the form of mean and standard deviation (μ ± σ).

Tables Icon

Table 3 Oxygen saturation results through leave-one-out. For each subject, the mean of the gradients of the lines of best fit to the data from all other subjects is used as the gradient β of the linear relationship between the data and the oxygen saturation. The intercept c is instead found by using the first minute of data from the subject. The results indicate that the method can not only be used to track oxygen saturation changes, but effectively measure it based on a training data across similar skin colours and under ideal conditions.

Equations (15)

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

R c = λ c L ( λ , x , t ) s ( λ , x , t ) r c ( λ , t )
L ( λ , t ) = l ( x , t ) L ^ ( λ )
r c ( λ , t ) = r c ( λ )
s ( λ , t ) = m ( λ , x ) b ( λ , x , t )
b ( λ , x , t ) = v ( x , t ) b DC ( λ , t ) + Δ v ( x , t ) b AC ( λ , t )
R c ( t ) = l ( x , t ) λ c L ^ ( λ ) r c ( λ ) m ( λ , x ) [ v ( x , t ) b DC ( λ , t ) + Δ v ( x , t ) b AC ( λ , t ) ]
R ^ c ( t ) = l ( x , t ) λ c L ^ ( λ ) r c ( λ ) m ( λ , x ) Δ v ( x , t ) b AC ( λ , t ) l ( x , t ) λ c L ^ ( λ ) r c ( λ ) m ( λ , x ) v ( x , t ) b DC ( λ , t ) = Δ v ( x , t ) λ c L ^ ( λ ) r c ( λ ) m ( λ , x ) b AC ( λ , t ) v ( x , t ) λ c L ^ ( λ ) r c ( λ ) m ( λ , x ) b DC ( λ , t )
S ( t ) = R ^ 1 R ^ 2 = λ 1 L ^ ( λ ) r c ( λ ) m ( λ , x ) b AC ( λ , t ) λ 1 L ^ ( λ ) r c ( λ ) m ( λ , x ) b DC ( λ , t ) λ 2 L ^ ( λ ) r c ( λ ) m ( λ , x ) b DC ( λ , t ) λ 2 L ^ ( λ ) r c ( λ ) m ( λ , x ) b AC ( λ , t ) = A C 1 / D C 1 A C 2 / D C 2
m ( λ , x ) = m ( λ )
SNR = SNR { x ( t ) } a b = 10 log ( 𝒱 | { x ( t ) } | 2 d f ( 1 𝒱 ) | { x ( t ) } | 2 d f )
𝒱 ( f ) = [ δ ( f f ^ ) + δ ( f 2 f ^ ) ] * Π ( ± f h ) )
P i = { 1 , if | ϕ g i ( f ^ HR ) ϕ G ( f ^ HR ) | < π 2 0 , otherwise
L i = L HR i L BR i L PH i = ( SNR HR i > SNR HR thresh ) ( SNR BR i < SNR BR thresh ) P i
ω i = SNR HR i M ( SNR HR i ) , { i : L i = 1 }
E = β log ( S ) + c

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