Medical & Biological Engineering & Computing

, Volume 50, Issue 12, pp 1239–1247 | Cite as

Novel non-invasive method of measurement of endothelial function: enclosed-zone flow-mediated dilatation (ezFMD)

  • Teiji Ukawa
  • Tsuneo Takayanagi
  • Haruka Morimoto
  • Yukihito Higashi
  • Naomi Idei
  • Masao Yoshizumi
  • Toshio Tsuji
Original Article


Measurement of flow-mediated dilatation (FMD) is the conventional non-invasive method for assessment of endothelial function; however, it requires an expensive ultrasound system and high levels of technical skill. Therefore, we developed a novel method for measurement of endothelial function, namely, measurement of ezFMD. ezFMD estimates the degree of vasodilatation from the oscillation signals transmitted to a sphygmomanometer cuff attached to the upper arm. The objective of this study was to validate the principle underlying the measurement of ezFMD, and to evaluate the repeatability of the ezFMD measurements. We observed the blood vessel behavior and oscillometric pattern in ten subjects. When the cuff was inflated to the level of the mean blood pressure, the oscillation amplitude increased with increasing degree of vasodilatation. In experiment to evaluate the repeatability of the ezFMD measurement, the average difference between the paired measurements was 3.7 %, the standard deviation was 11.5 %, and the average coefficient of variation value for the 11 paired measurements was 23.7 %. These results suggest the validity of the principle underlying the measurement of the ezFMD for the assessment of endothelial function. And, this study suggests that the repeatability of the ezFMD measurements is superior to that of the conventional measurement of FMD.


Atherosclerosis Endothelial function FMD Oscillometric sphygmomanometer ezFMD 


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Copyright information

© International Federation for Medical and Biological Engineering 2012

Authors and Affiliations

  • Teiji Ukawa
    • 1
    • 5
  • Tsuneo Takayanagi
    • 1
  • Haruka Morimoto
    • 1
  • Yukihito Higashi
    • 2
  • Naomi Idei
    • 3
  • Masao Yoshizumi
    • 4
  • Toshio Tsuji
    • 5
  1. 1.Nihon Kohden CorporationTokyoJapan
  2. 2.Department of Regeneration and Medicine, Research Institute for Radiation Biology and Medicine, Research Center for Radiation Genome MedicineHiroshima UniversityHiroshimaJapan
  3. 3.Department of Cardiovascular Physiology and MedicineHiroshima University Graduate School of Biomedical SciencesHiroshimaJapan
  4. 4.Department of Cardiovascular MedicineHiroshima University Graduate School of Biomedical SciencesHiroshimaJapan
  5. 5.Hiroshima University Graduate School of EngineeringHigashi-HiroshimaJapan

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