Autor: |
Colombo L; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy., Pagliazzi M; ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain., Sekar SKV; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy., Contini D; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy., Mora AD; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy., Spinelli L; Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milano, Italy., Torricelli A; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy.; Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milano, Italy., Durduran T; ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain.; Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain., Pifferi A; Politecnico di Milano, Dipartimento di Fisica, Milano, Italy.; Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milano, Italy. |
Abstrakt: |
Time-domain diffuse correlation spectroscopy (TD-DCS) is an emerging noninvasive optical technique with the potential to resolve blood flow (BF) and optical coefficients (reduced scattering and absorption) in depth. Here, we study the effects of finite temporal resolution and gate width in a realistic TD-DCS experiment. We provide a model for retrieving the BF from gated intensity autocorrelations based on the instrument response function, which allows for the use of broad time gates. This, in turn, enables a higher signal-to-noise ratio that is critical for in vivo applications. In numerical simulations, the use of the proposed model reduces the error in the estimated late gate BF from 34% to 3%. Simulations are also performed for a wide set of optical properties and source-detector separations. In a homogeneous phantom experiment, the discrepancy between later gates BF index and ungated BF index is reduced from 37% to 2%. This work not only provides a tool for data analysis but also physical insights, which can be useful for studying and optimizing the system performance. |