Determination of Reflectance Optical Sensor Array Configuration Using 3-Layer Tissue Model and Monte Carlo Simulation

Abstract

A new reflectance optical sensor array for locating fetal signal transabdominally has been determined in this study. The selection of optical sensor array is based on the highest Irradiance (μW/m 2 ) value estimated on respected detectors. A three-layer semi-infinite tissue model which consists of maternal, amniotic fluid sac and fetal tissues is employed to study the optical sensor array configuration. By using statistical error approach, the number of rays injected to the system can be set to 1 million rays with ±3.2% of simulation error. The simulation results obtained from Monte Carlo technique reveal that diamond configuration is the most suitable configuration of reflectance optical sensor array with 40mm of emitter-detector separation. The selected configuration will be useful in detecting fetal signal independently of probe position.

Development of physical 3D model of maternal-fetal to study light interaction through tissue

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“…To authors knowledge, Jacques et.al (2000) modelling the pregnant woman abdominal surface as an arc of 10cm while the fetal brain is treated as an overlapping small spheres with the overall diameter of 8cm. Meanwhile, [7] and [8] used a semi-infinite tissue model which comprise of three different layers (maternal, amniotic fluid and fetal) to represent the pregnant woman model. For that reason, a model resembles physical 3D pregnant woman curvature is being proposed in this paper.…”

Investigating the Effect of Total Radiated Power on Fetus Using Optical Simulation Approach Based on Exposure Safety Limit for Eye and Tissue Injury

“…To avoid such invasive interference, a transabdominal fetal pulse oximetry system has been introduced [2]- [5]. Regarding the transabdominal fetal pulse oximetry, there are several studies that have been conducted to maximize the output received by the fetal detectors such as case studies involving the determination of the suitable emitterdetector spacing [6], the arrangement of optical array for fetal reflectance probes [7] as well as the best selection for wavelength pairs to be applied as the light source in the fetus pulse oximetry system [2], [8].…”