Results 51 to 60 of about 7,515 (209)

Spatiotemporal processing in photoplethysmography for skin microcirculatory perfusion imaging

Biomedical Optics Express, 2022
Technological advances in the real-time visualization of cutaneous microcirculation aim to realize benefits including high-resolution imaging, suppressed noise, and robust temporal coherence. Photoplethysmography (PPG), a noninvasive technique that measures single or multiple points of relative blood volume changes in blood vessels under the skin ...
Dongkai, Cheng, Jiabin, Wang, Tomoyuki, Yokota, Takao, Someya   +3 more
openaire   +2 more sources

Noncontact imaging photoplethysmography to effectively access pulse rate variability [PDF]

Journal of Biomedical Optics, 2012
Noncontact imaging photoplethysmography (PPG) can provide physiological assessment at various anatomical locations with no discomfort to the patient. However, most previous imaging PPG (iPPG) systems have been limited by a low sample frequency, which restricts their use clinically, for instance, in the assessment of pulse rate variability (PRV). In the
Yu, Sun, Sijung, Hu, Vicente, Azorin-Peris, Roy, Kalawsky, Stephen, Greenwald   +4 more
openaire   +2 more sources

Improvements in Remote Cardiopulmonary Measurement Using a Five Band Digital Camera [PDF]

, 2014
Remote measurement of the blood volume pulse via photoplethysmography (PPG) using digital cameras and ambient light has great potential for healthcare and affective computing. However, traditional RGB cameras have limited frequency resolution. We present
Gontarek, Sarah, McDuff, Daniel Jonathan, Picard, Rosalind W.   +2 more
core   +1 more source

Hybrid Optical Unobtrusive Blood Pressure Measurements

Sensors, 2017
Blood pressure (BP) is critical in diagnosing certain cardiovascular diseases such as hypertension. Some previous studies have proved that BP can be estimated by pulse transit time (PTT) calculated by a pair of photoplethysmography (PPG) signals at two ...
Guangfei Zhang, Caifeng Shan, Ihor Kirenko, Xi Long, Ronald M. Aarts   +4 more
doaj   +1 more source

Contact Surface Area: A Novel Signal for Heart Rate Estimation in Smartphone Videos

, 2019
We consider the problem of smartphone video-based heart rate estimation, which typically relies on measuring the green color intensity of the user's skin.
Fridovich-Keil, Sara, Ramadge, Peter J.
core   +1 more source

Monitoring of the central blood pressure waveform via a conformal ultrasonic device. [PDF]

, 2018
Continuous monitoring of the central-blood-pressure waveform from deeply embedded vessels, such as the carotid artery and jugular vein, has clinical value for the prediction of all-cause cardiovascular mortality. However, existing non-invasive approaches,
Bhaskaran, Shubha, Chen, Yimu, Chen, Zeyu, Gong, Hua, Gu, Yue, Guo, Yuxuan, Hu, Hongjie, Huang, Brady, Huang, Zhenlong, Lei, Yusheng, Li, Xiaoshi, Li, Yang, Lin, Muyang, Makihata, Mitsutoshi, Pisano, Albert P, Wang, Chonghe, Wang, Chunfeng, Xu, Sheng, Yin, Zhenan, Zhang, Liangfang, Zhang, Lin, Zhang, Tianjiao, Zhang, Zhuorui, Zhou, Qifa   +23 more
core   +1 more source

DistancePPG: Robust non-contact vital signs monitoring using a camera

, 2015
Vital signs such as pulse rate and breathing rate are currently measured using contact probes. But, non-contact methods for measuring vital signs are desirable both in hospital settings (e.g. in NICU) and for ubiquitous in-situ health tracking (e.g.
Kumar, Mayank, Sabharval, Ashutosh, Veeraraghavan, Ashok   +2 more
core   +1 more source

The effects of optical sensor-tissue separation in endocavitary photoplethysmography [PDF]

, 2018
Objective: Intestinal anastomotic failure that occurs mainly due to ischaemia is a serious risk in colorectal cancer patients undergoing surgery. Surgeons continue to rely on subjective methods such as visual inspection to assess intestinal viability ...
Kyriacou, P. A., Patel, Z., Thaha, M. A.
core   +3 more sources

Ultra‐Flexible Dual‐Band Organic Photodetectors for Visible and Near‐Infrared Sensing

Advanced Optical Materials, EarlyView.
An ultra‐flexible dual‐band organic photodetector with a total thickness of 5.6 µm for bio‐sensing is developed. It selectively detects visible and near‐infrared light with high sensitivity by switching the voltage. Peripheral oxygen saturation (SpO2) measurement is demonstrated using the device attached to a finger under a single light source by ...
Sachi Awakura, Hiroaki Jinno, Yusaku Tagawa, Ryota Fukuzawa, Masahito Takakuwa, Takao Someya, Tomoyuki Yokota   +6 more
wiley   +1 more source

A Reproducible Study on Remote Heart Rate Measurement [PDF]

, 2017
This paper studies the problem of reproducible research in remote photoplethysmography (rPPG). Most of the work published in this domain is assessed on privately-owned databases, making it difficult to evaluate proposed algorithms in a standard and ...
Anjos, André, Heusch, Guillaume, Marcel, Sébastien   +2 more
core   +1 more source