سامانه همایش های دانشگاه آزاد اسلامی واحد نجف آباد

صفحه اصلی / اولین همایش بین المللی تحول خدمات سلامت: تلفیق مراقبت، درمان، بازتوانی و امیدبخشی

Effect of Arterial Depth in Skin Tissue on Photoplethysmographic Signal Characteristics: An Bio- Optical Study

نویسندگان :

Amirhossein Rezaei Latifi¹ Ali Rezaei -Latifi²

1- Hormozgan University of Medical Science, 2- University of Hormozgan

کلمات کلیدی :

Photoplethysmography (PPG،Arterial depth،Monte Carlo Simulation،Light scattering،Skin optics

چکیده :

Background: Arterial depth is an important factor affecting light-tissue interaction and Photoplethysmography (PPG) signal formation. This study investigated the effect of arterial depth on reflective PPG signal characteristics using a bio-optical simulation model. Method: A computational simulation study was performed using a nine-layer skin model. Photon transport was simulated by the Monte Carlo method in Zemax OpticStudio, while tissue scattering was modeled using the Henyey-Greenstein phase function. Pulsatile blood-volume variations during one cardiac cycle were generated in Python and integrated into the optical model. To isolate the effect of arterial depth, optical and physiological parameters were kept constant while the pulsatile arterial compartment was assigned to different skin layers. Findings: The simulated signals showed good agreement with measured waveforms in terms of systolic and diastolic peaks, dicrotic notch, and waveform periodicity. Signal amplitude and power varied nonlinearly with arterial depth. Superficial arterial locations produced lower amplitudes, intermediate depths generated the highest signal power, and deeper layers showed signal attenuation due to increased absorption and scattering losses. The AC/DC ratio also changed with arterial position, indicating depth-dependent pulsatile detectability. Conclusion: Arterial depth significantly influences reflective PPG signals through its interaction with photon transport and blood-volume distribution. The findings may contribute to improved sensor placement, optical design, and interpretation of non-invasive PPG measurements.