Skip main navigation
Close Drawer MenuOpen Drawer Menu
×

Smartphone-Based Blood Pressure Measurement Using Transdermal Optical Imaging Technology

Originally published6 Aug 2019https://doi.org/10.1161/CIRCIMAGING.119.008857Circulation: Cardiovascular Imaging. 2019;12

    Abstract

    Background:

    Cuff-based blood pressure measurement lacks comfort and convenience. Here, we examined whether blood pressure can be determined in a contactless manner using a novel smartphone-based technology called transdermal optical imaging. This technology processes imperceptible facial blood flow changes from videos captured with a smartphone camera and uses advanced machine learning to determine blood pressure from the captured signal.

    Methods:

    We enrolled 1328 normotensive adults in our study. We used an advanced machine learning algorithm to create computational models that predict reference systolic, diastolic, and pulse pressure from facial blood flow data. We used 70% of our data set to train these models and 15% of our data set to test them. The remaining 15% of the sample was used to validate model performance.

    Results:

    We found that our models predicted blood pressure with a measurement bias±SD of 0.39±7.30 mm Hg for systolic pressure, −0.20±6.00 mm Hg for diastolic pressure, and 0.52±6.42 mm Hg for pulse pressure, respectively.

    Conclusions:

    Our results in normotensive adults fall within 5±8 mm Hg of reference measurements. Future work will determine whether these models meet the clinically accepted accuracy threshold of 5±8 mm Hg when tested on a full range of blood pressures according to international accuracy standards.

    Footnotes

    *Drs Luo, Yang, and Barszczyk are joint first authors.

    The Data Supplement is available at https://www.ahajournals.org/doi/suppl/10.1161/CIRCIMAGING.119.008857.

    Kang Lee, PhD, Dr Eric Jackman Institute of Child Study, University of Toronto, 45 Walmer Rd, Toronto, ON M5R 2X2, Canada, Email
    Zhong-Ping Feng, MD, PhD, Department of Physiology, University of Toronto, Medical Sciences Bldg, Room 3306, 1 King’s College Cir, Toronto, ON M5S 1A8, Canada, Email

    References

    • 1. Kearney PM, Whelton M, Reynolds K, Muntner P, Whelton PK, He J. Global burden of hypertension: analysis of worldwide data.Lancet. 2005; 365:217–223. doi: 10.1016/S0140-6736(05)17741-1Google Scholar
    • 2. D’Agostino RB, Vasan RS, Pencina MJ, Wolf PA, Cobain M, Massaro JM, Kannel WB. General cardiovascular risk profile for use in primary care: the Framingham Heart Study.Circulation. 2008; 117:743–753. doi: 10.1161/CIRCULATIONAHA.107.699579Google Scholar
    • 3. Whelton PK, Carey RM, Aronow WS, Casey DE, Collins KJ, Dennison Himmelfarb C, DePalma SM, Gidding S, Jamerson KA, Jones DW, MacLaughlin EJ, Muntner P, Ovbiagele B, Smith SC, Spencer CC, Stafford RS, Taler SJ, Thomas RJ, Williams KA, Williamson JD, Wright JT. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.Hypertension. 2018; 71:e13–e115. doi: 10.1161/HYP.0000000000000065Google Scholar
    • 4. Kikuya M, Hansen TW, Thijs L, Björklund-Bodegård K, Kuznetsova T, Ohkubo T, Richart T, Torp-Pedersen C, Lind L, Ibsen H, Imai Y, Staessen JA; International Database on Ambulatory blood pressure monitoring in relation to Cardiovascular Outcomes Investigators. Diagnostic thresholds for ambulatory blood pressure monitoring based on 10-year cardiovascular risk.Circulation. 2007; 115:2145–2152. doi: 10.1161/CIRCULATIONAHA.106.662254Google Scholar
    • 5. Stephens MB, deGruy F. Clinical inquiries. Does ambulatory blood pressure monitoring aid in the management of patients with hypertension?J Fam Pract. 2002; 51:15.Google Scholar
    • 6. Scakacs J, Ackers I, Rodriguez J, Ojong-Egbe O, Casapulla S. Effectiveness of home blood pressure monitoring among low-income adults in rural appalachia.J Am Osteopath Assoc. 2016; 116:288–294. doi: 10.7556/jaoa.2016.058Google Scholar
    • 7. Parati G, Ochoa JE. Chapter 2: home (Self) monitoring of blood pressure.White WB, ed. In: Blood Pressure Monitoring in Cardiovascular Medicine and Therapeutics. Cham: Springer International Publishing; 2015:15–43.Google Scholar
    • 8. Viera AJ, Tuttle L, Zeng J. Dollars and discomfort: what will people be willing to give for better blood pressure assessment?J Clin Hypertens (Greenwich). 2016; 18:422–423. doi: 10.1111/jch.12680Google Scholar
    • 9. Westhoff TH, Straub-Hohenbleicher H, Schmidt S, Tölle M, Zidek W, van der Giet M. Convenience of ambulatory blood pressure monitoring: comparison of different devices.Blood Press Monit. 2005; 10:239–242.Google Scholar
    • 10. Liu J, Luo H, Zheng PP, Wu SJ, Lee K. Transdermal optical imaging revealed different spatiotemporal patterns of facial cardiovascular activities.Sci Rep. 2018; 8:10588. doi: 10.1038/s41598-018-28804-0Google Scholar
    • 11. Wei J, Luo H, Wu SJ, Zheng PP, Fu G, Lee K. Transdermal optical imaging reveal basal stress via heart rate variability analysis: a novel methodology comparable to electrocardiography.Front Psychol. 2018; 9:98. doi: 10.3389/fpsyg.2018.00098Google Scholar
    • 12. Verkruysse W, Svaasand LO, Nelson JS. Remote plethysmographic imaging using ambient light.Opt Express. 2008; 16:21434–21445. doi: 10.1364/oe.16.021434Google Scholar
    • 13. Chandrasekhar A, Kim CS, Naji M, Natarajan K, Hahn JO, Mukkamala R. Smartphone-based blood pressure monitoring via the oscillometric finger-pressing method.Sci Transl Med. 2018; 10:eaap8674. doi:10.1126/scitranslmed.aap8674Google Scholar
    • 14. Rouast PV, Adam MTP, Chiong R, Cornforth D, Lux E. Remote heart rate measurement using low-cost RGB face video: a technical literature review.Front Comput Sci. 2018; 12:858–872.Google Scholar
    • 15. Lee K, Zheng P, inventors. System and method for detecting invisible human emotion.Google Patent WO2016049757A1. March 7, 2016.Google Scholar
    • 16. Yamakoshi KI, Shimazu H, Togawa T. Indirect measurement of instantaneous arterial blood pressure in the human finger by the vascular unloading technique.IEEE Trans Biomed Eng. 1980; 27:150–155. doi: 10.1109/TBME.1980.326616Google Scholar
    • 17. Sawada Y, Yamakoshi K, Shimazu H. Vascular unloading method for noninvasive measurement of instantaneous arterial pressure: applicability in psychophysiological research.Psychophysiology. 1983; 20:709–714.Google Scholar
    • 18. Fox RH, Goldsmith R, Kidd DJ. Cutaneous vasomotor control in the human head, neck and upper chest.J Physiol. 1962; 161:298–312. doi: 10.1113/jphysiol.1962.sp006887Google Scholar
    • 19. Armstrong C; Joint National Committee. JNC8 guidelines for the management of hypertension in adults.Am Fam Physician. 2014; 90:503–504.Google Scholar
    • 20. Provost F. Machine learning from imbalanced data sets 101.AAAI Technical Report WS-00-05;2000.Google Scholar
    • 21. Kamshilin AA, Margaryants NB. Origin of photoplethysmographic waveform at green light.Phys Procedia. 2017; 86:72–80.Google Scholar
    • 22. Gorban AN, Kégl B, Wunsch DC, Zinovyev A. Principal Manifolds for Data Visualization and Dimension Reduction. Berlin, Heidelberg: Springer Science & Business Media; 2007.Google Scholar
    • 23. Avolio AP, Butlin M, Walsh A. Arterial blood pressure measurement and pulse wave analysis–their role in enhancing cardiovascular assessment.Physiol Meas. 2010; 31:R1–47. doi: 10.1088/0967-3334/31/1/R01Google Scholar
    • 24. Association for the Advancement of Medical Instrumentation.ANSI/AAMI/ISO 81060–1:2007/(R)2013.Google Scholar
    • 25. Zhang Y, Tai C, Chi C, Protogerou AD, Blacher J, Safar ME. Pulse pressure and pulse pressure amplification as biomarkers in cardiovascular disease.Patel VB, Preedy VR, eds. In: Biomarkers in Cardiovascular Disease. Dordrecht: Springer Netherlands; 2016:917–933.Google Scholar

    Or Purchase

    Purchase Save for later
    Restore content access
    This functionality works only for purchases made as a guest