Determination of cardiac frequency and blood pulse transit time mapping using video techniques

• Grant number: 17/01932-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2017
• End date: December 31, 2017
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: George Cunha Cardoso
• Grantee: Matheus Bigatão Martinelli
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Photyplethysmography (PPG) is a non-invasive optical method used for clinical measurements of blood volume, cardiac frequency and blood oxygenation. The PPG signal comes from light absorption intensity changes, measured by a photoreceptor, related blood volume variation due to heartbeats. However, despite being a non-invasive method, PPG requires contact to skin what is inconvenient for cases of sensitive skin such as burn patients, senior citizens and babies. Thus, alternatives have been searched and one of the most significant alternatives to PPG is image-PPG. Image PPG is a relatively recent technique that does not require contact to tissues and has been showing very promising results. However, image-PPG still requires further research and development before it can become a well stablished technique. In image-PPG, the circulatory system time-varying signals are contained in color shifts of video image acquired by a camera. The goal of this project is to measure blood pulse transit time using image-PPG and to test the method in a sample of volunteers with skin tones representative for the Brazilian population. Experiments will include acquisition and processing of images with algorithms we have been developing that are in the tests stage. We will use finger PPG's to validate the results. The results will be analyzed with chi-square statistical methods where the pulse transit times as measure by PPGs will be compared to the results obtained by the image-PPG methods under development. With sufficient signal to noise ratio, it is possible to create an image map of the phase of the blood pulse and overlay it to the image of the region of interest. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MARTINELLI, MATHEUS B.; DOMINGUEZ, CHRISTIAN T.; BACHMANN, LUCIANO; CARDOSO, GEORGE C.; TUCHIN, VV; LEAHY, MJ; WANG, RK. Heart-rate modulation of non-vascularized epidermis optical attenuation coefficient. DYNAMICS AND FLUCTUATIONS IN BIOMEDICAL PHOTONICS XVI, v. 10877, p. 7-pg., 2019-01-01. (17/01932-5, 13/07276-1)