Reflection photoplethysmography of arterial-blood-volume pulses

Weinman, J.; Hayat, Abul; Raviv, Gil

doi:10.1007/bf02441571

Cited by 53 publications

(25 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This facilitates a more robust resistance to artifact or noise but shortening the duration of total time. 9,23,32,49,50 This was represented in the green and blue wavelengths producing significantly greater signal/noise ratios compared with that of red and infrared for the same and different skin types. Overall the green wavelength was significantly different across varying skin types compared to all other wavelengths.…”

Section: Discussionmentioning

confidence: 99%

“…44,50 The sensor then interprets the inverse of the absorption in relation to blood volume in the tissue. 49 By detecting the change in the fluctuation of hemoglobin in the radial artery, a PPG-based device is able to determine pulse rate. This is represented by the AC current change.…”

Section: Discussionmentioning

confidence: 99%

“…6,16,49,50 The main concern with PPG technology for detection of pulse rate is related to the melanin concentration of the skin and its related pigmenting of skin. 3,20,50 Melanin is known to be highly absorbent to light, and thereby attenuating the incident light wavelength.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Influence of skin type and wavelength on light wave reflectance

Fallow

Tarumi

Tanaka

2013

J Clin Monit Comput

129

View full text Add to dashboard Cite

DedicationIn dedication to my family, friends, and Jessie for whom I could of not done this without.Their constant support, faith and encouragement provided me with the strength and passion that allowed me to pursue my dreams. They are my foundation and worked just as hard as I did being here for me. Thank you with all my heart and love.v Acknowledgements A very special thanks to Dr. Tanaka my primary investigator and advisor, whom kept me on track and taught me that research, is more than just knowledge; it is a complete pursuit and dedication. His ability to drive and teach were great examples and helped me grow as a graduate student and researcher but also as a person. Thanks to Dr.Brothers for being my second reader and providing a second set of eyes to my ideas. Heart rate monitoring (HRM) is an essential tool for monitoring physical activity and as a diagnostic tool in the clinical setting. The ability to monitor heart rate gives users and clinicians vital information about the current condition of the cardiovascular system before, during, and after exercise. However, HRM requires a telemetric chest strap, and comfort, transmission and fit can become problems with the chest strap. New technology using photoplethysmography (PPG) has emerged recently to provide the possibility of HRM without a telemetric chest strap during exercise. The aim of this study was to determine if a new device could detect heart rate over a broad range of skin types (I-V), and whether what wavelength would be most suitable for detecting the signals. A light emitting diode (LED) based PPG system was used to determine heart rate by change in pulsatile blood flow on 22 apparently healthy individuals (11 male and 11 female, 20-59 years old) of varying skin type. Skin type was classified according to a questionnaire in combination with digital photographs with a skin type chart. Each subject was exposed to four different wavelengths (470 nm, 520 nm, 630 nm, and 880 nm) and multiple trials were conducted on each wavelength. Heart rate detection was vii represented by modulation of the incident light wave and normalized by saturation into a pulsatile waveform represented as modulation average. The 520nm wavelength classified as visible green light provided a significantly greater (p<0.001) ability to detect heart rate. Increasing levels of melanin, or darker skin type (Type V) showed decreased modulation however this trend was not significant (p<0.067). There was no significant interaction between the wavelength of light and the skin type. In conclusion, a PPG based device can detect heart rate across skin types and use of a green light wavelength provides an even greater resolution.viii

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of skin type and wavelength on light wave reflectance

Fallow

Tarumi

Tanaka

2013

J Clin Monit Comput

129

View full text Add to dashboard Cite

show abstract

“…As seen above, the changes in the modulation ratio reflect changes in oxygenation; however, it is more difficult to discern oxygenation differences at higher perfusion rates. This may be due to the dependence of the reflectance signal on the particular arrangement of vessels in the phantom [47]. In the case of low perfusion or occluded vessels, the modulation ratio has been reported to increase [13].…”

Section: In-vitro Phantom Experiments Resultsmentioning

confidence: 99%

“…This signal is relatively independent of perfusion, although with increased blood flow the path length of a photon will most likely encounter more blood than in the case where the perfusion is lower [47]. This results in an average decrease in light signal intensity consistent with higher blood volume.…”

Section: In-vitro Measurement Systemmentioning

confidence: 97%

In-silico and in-vitro investigation of a photonic monitor for intestinal perfusion and oxygenation

Robinson

Butcher

Wilson

et al. 2017

Biomed. Opt. Express

View full text Add to dashboard Cite

Abstract:The quantification of visceral organ oxygenation after trauma-related systemic hypovolemia and shock is critical to enable effective resuscitation. In this work, a photoplethysmography-based (PPG) sensor was specifically designed for probing the perfusion and oxygenation condition of intestinal tissue with the ultimate goal to monitor patients post trauma to guide resuscitation. Through Monte Carlo modeling, suitable optofluidic phantoms were determined, the wavelength and separation distance for the sensor was optimized, and sensor performance for the quantification of tissue perfusion and oxygenation was tested on the in-vitro phantom. In particular, the Monte Carlo simulated both a standard block three-layer model and a more realistic model including villi. Measurements were collected on the designed three layer optofluidic phantom and the results taken with the small form factor PPG device showed a marked improvement when using shorter visible wavelengths over the more conventional longer visible wavelengths. Overall, in this work a Monte Carlo model was developed, an optofluidic phantom was built, and a small form factor PPG sensor was developed and characterized using the phantom for perfusion and oxygenation over the visible wavelength range. The results show promise that this small form factor PPG sensor could be used as a future guide to shock-related resuscitation.

show abstract

A microminiature photoplethysmograph probe for microvascular surgery

Doyle

Eng

1984

Microsurgery

View full text Add to dashboard Cite

The technique of reflection photoplethysmography has proven to be a useful tool in plastic and reconstructive surgery, especially in monitoring the circulation of pedicle flaps' and free-flap transfer^.^ At the microvascular service at Toronto General Hospital, we recently began using this technique as an adjunct to the clinical and temperature assessment of digital replantations and toe-to-thumb transfers, but were faced with the problem that commercially available photoplethysmograph probes were simply too large and difficult to reliably mount on most digits, especially when a temperature probe was also attached to the digit to obtain simultaneous temperature measurements. The problem was exacerbated by the requirement that the probe could not be mounted by use of circumferential taping for fear of compromising blood flow in the replanted part. In response to this problem we have developed a new microminiature photoplethysmograph probe suitable for monitoring replanted digits. Figure 1 shows the new photoplethysmograph probe compared to the larger commercially available Medasonics Photopulse probe. Figure 2 shows the unit mounted. The probe consists of an inexpensive ($3 .OO), microminiature lightemitting diode (LED) and phototransistor assembly (Litronix model SFH900) usually used for data processing applications. This device is connected up as follows. The LED cathode and phototransistor emitter are connected to ground. The LED anode is connected to 5 V through a 100-62 resistor. The phototransistor collector is connected to 5 V through a 1,OOO-Q resisitor. Finally, the collector signal is high-pass filtered, amplified, and displayed on a chart recorder. We have found that a simple R-C high-pass filter with a time-constant in the range of 1-5 s works well. We used an amplifier gain of 100, using a simple operational amplifier design. Where 60-Hz electrical interference is a problem, a simple R-C low-pass filter may be connected between the amplifier output and the chart recorder. Figure 3 shows a recording obtained using the new probe. PROBE DESIGNIt is hoped that this new photoplethysmograph design will prove to be useful to others, as it has been to us, in the postoperative assessment of replanted digits. Figure 1. New, smaller, photoplethysrnograph probe compared to a popular commercially available probe (Medasonics).

show abstract

Reflection photoplethysmography of arterial-blood-volume pulses

Cited by 53 publications

References 9 publications

Influence of skin type and wavelength on light wave reflectance

Influence of skin type and wavelength on light wave reflectance

In-silico and in-vitro investigation of a photonic monitor for intestinal perfusion and oxygenation

A microminiature photoplethysmograph probe for microvascular surgery

Contact Info

Product

Resources

About