Advances in Optical Imaging and Photon Migration最新文献_第4页

Images of Inhomogeneous Turbid Media Using Diffuse Photon Density Waves 利用漫射光子密度波成像非均匀浑浊介质

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1994.apmpdwi.106

M. A. O'Leary, D. Boas, B. Chance, A. Yodh

{"title":"Images of Inhomogeneous Turbid Media Using Diffuse Photon Density Waves","authors":"M. A. O'Leary, D. Boas, B. Chance, A. Yodh","doi":"10.1364/aoipm.1994.apmpdwi.106","DOIUrl":"https://doi.org/10.1364/aoipm.1994.apmpdwi.106","url":null,"abstract":"In this paper we present images derived from measurements of diffuse photon density waves in turbid media. After a brief introduction and description of the experimental set-up, this document is divided into two sections.\u0000 In the first, we present an analytic solution for the scattering of diffuse photon density waves by spherical and cylindrical inhomogeneities within turbid media and discuss the application of this solution to systems containing multiple objects and multiple sources. This exact solution is a useful tool for simulating the distortion of a diffuse photon density wave due to simple inhomogeneities. Until recently, simulations of heterogeneous media were achieved by Monte-Carlo methods, finite element analysis, or other time consuming techniques. More recently, Feng et al. [1] presented a perturbative solution for a single, point-like heterogeneity. The exact calculation we present is not limited to small objects, and numerical calculations using this solution are fast compared to Monte Carlo simulations[2]. Finally, we experimentally demonstrate that this analytic solution enables us to fit for the optical and geometric properties of arbitrary spherical and cylindrical objects, and we discuss the detector sensitivity required to characterize such objects.\u0000 In the second section we derive images of more general inhomogeneous scattering media. Our method is based on the diffusion approximation, but is not an iterative approach; it is a direct inversion that is exact to first order in variations of the sample absorption. An increase in sensitivity is achieved through the use of multiple-source/single-detector units placed around the turbid medium. In our particular case, each unit consisted of a set of two modulated diffuse light sources phased 180° out of phase with respect to one another, and a single detector located at positions equidistant from each source. In this report we will describe the general theoretical approach, provide experimental evidence of its utility, and discuss potential applications.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124930752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A System for Solving the Forward and Inverse Problems in Optical Spectroscopy and Imaging 光学光谱与成像正逆问题求解系统

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.ria264

M. Schweiger, S. Arridge

引用次数: 9

Analytic Solution to the Inverse Problem in Diffusion Tomography 扩散层析成像反问题的解析解

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.pmst32

J. Schotland

引用次数: 0

Fluorescence and Phosphorescence Lifetime-Based Sensing in Tissues 组织中基于寿命的荧光和磷光传感

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1994.trbsdi.156

E. Sevick-Muraca, C. Burch

引用次数: 0

Experimental Evidence for Loop-Type Photon Trajectories in Random Media with Strong Disorder 强无序随机介质中环型光子轨迹的实验证据

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1994.wpl.25

D. Wiersma, M. P. V. Albada, A. Lagendijk

引用次数: 0

Optical detection of abnormally absorbing regions in tissue 组织中异常吸收区的光学检测

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.mt183

A. Gandjbakhche, V. Chernomordik, R. Bonner, R. Nossal, G. Weiss, J. Hebden

引用次数: 1

Influence of Clear Cerebrospinal Fluid on NIR Brain Imaging and Cerebral Oxygenation Monitoring 清脑脊液对近红外脑成像和脑氧监测的影响

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.opc372

Hanli Liu, D. Boas, A. Yodh, B. Chance

引用次数: 2

Failure of radiative transport theory in homogeneous scattering media to predict the Point Spread Function (PSF) of transillumination images through some biologic tissues 均匀散射介质中的辐射输运理论无法预测穿透某些生物组织的透照图像的点扩散函数

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.pmst35

C. Depeursinge, F. Bevilacqua, P. Marquet

{"title":"Failure of radiative transport theory in homogeneous scattering media to predict the Point Spread Function (PSF) of transillumination images through some biologic tissues","authors":"C. Depeursinge, F. Bevilacqua, P. Marquet","doi":"10.1364/aoipm.1996.pmst35","DOIUrl":"https://doi.org/10.1364/aoipm.1996.pmst35","url":null,"abstract":"Monte Carlo simulations or, to a lesser degree of accuracy, the resolution of the diffusion are generally considered as giving reasonable evaluations of the photon irradiance in tissues, globally described by the radiative transport theory. They are frequently used to calculate the Point Spread Function (PSF) describing the sharpness of transillumination images, resolved either in time or in frequency domain. The PSF is itself completely determined, for an homogenous slab of tissue and in the approximation of the diffusion equation, by the reduced scattering and absorption coefficients: µs' and µa respectively. For some tissue preparations, precise measurements of the PSF show, however, significant discrepancies between the predictions from µs′ and µa and the measured PSF. The propagation of light in biological tissues has been studied both theoretically by Monte Carlo simulations and experimentally in vitro on bovine and porcine liver, fat emulsions, human breast and brain tissues. Absorption and reduced scattering coefficients have been obtained and assessed by matching both the spatial and temporal profiles of a pulsed, collimated light beam to the experimental data. Measurements on fat emulsions and liver exhibit an excellent agreement between the predictions of the radiative transport theory for both spatial and temporal profiles. On the contrary, the spatial profile measured on adipose, breast and brain tissues are systematically too large to be predicted by the radiative transport theory in homogenous tissues. The tissue structure, in particular, the tissue micro and macroheterogeneities and possible site percolation in the model of light transport, not yet evidenced experimentally, could explain the unexpected broadening of the PSF in transillumination images through some tissues like adipose and brain .","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123962248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Finite Volumes on Noninvasive Frequency-Domain Measurements of Tissue Optical Properties 有限体积对组织光学特性无创频域测量的影响

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1994.apmpdwi.96

M. Patterson, B. Pogue

引用次数: 0

Image Reconstruction of Phantom with plural Absorbing Rods in Optical CT 光学CT中多重吸收棒对幻影图像重建的影响

Advances in Optical Imaging and Photon Migration Pub Date : 1900-01-01 DOI: 10.1364/aoipm.1996.ria290

H. Eda, I. Oda, Yasunobu Ito, Y. Wada

引用次数: 2