Obtaining optical and dynamic properties of biological tissues with diffuse optical spectroscopy

• Grant number: 19/25281-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: April 01, 2020
• End date: November 19, 2023
• Field of knowledge: Physical Sciences and Mathematics - Physics - General Physics
• Principal Investigator: Rickson Coelho Mesquita
• Grantee: Giovani Grisotti Martins
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 13/07559-3 - BRAINN - The Brazilian Institute of Neuroscience and Neurotechnology, AP.CEPID

Abstract

Material media in which incident radiation is highly scattered are known as turbid media. Such media can be characterized by their optical and dynamic properties, related to the concentration and the mean square displacement of their constituents that interact with the radiation. Diffuse optical spectroscopy techniques are capable of obtaining the properties of turbid media noninvasively and with high temporal resolution. Particularly, biological tissue behaves as a turbid medium for near-infrared radiation. Thus, optical diffusion techniques are able to measure the concentration of hemoglobin molecules, quantifying tissue oxygenation, as well as the mean square displacement of red blood cells, which can be associated with blood flow. Such properties make diffuse optical spectroscopy widely desired for in vivo applications. However, the accuracy in determining optical parameters has limitations, which may lead to misinterpretation based on unreliable results with high uncertainty. The goal of this research project is to develop methodologies capable of increasing the accuracy of optical and dynamic parameters estimated by diffuse optical spectroscopy techniques. The methodological development will be accompanied by different applications that aim to illustrate the power of quantifying biological tissue. In particular, we propose to create reference standard values of optical properties of several tissues in a group of subjects who are representative of the population of the state of São Paulo, and to correlate brain function with the absolute optical parameters. Finally, the propose to investigate the use of the absolute optical properties as a diagnostic biomarker in patients with Carotid Stenosis. (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)

FORTI, RODRIGO MENEZES; MARTINS, GIOVANI GRISOTTI; BAKER, WESLEY BOEHS; MESQUITA, RICKSON C.. Optimizing a two-layer method for hybrid diffuse correlation spectroscopy and frequency-domain diffuse optical spectroscopy cerebral measurements in adults. NEUROPHOTONICS, v. 10, n. 2, p. 26-pg., 2023-04-01. (19/25281-9, 13/07559-3)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MARTINS, Giovani Grisotti. Obtenção das propriedades ópticas e dinâmicas do tecido biológico com técnicas de espectroscopia óptica de difusão. 2024. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin Campinas, SP.