Advances in Optical Imaging and Photon Migration最新文献

{"title":"Perturbation Calculations of Photon Density Waves Interfering in an Inhomogeneous Tissue-Simulating Medium","authors":"B. Pogue, M. Patterson","doi":"10.1364/aoipm.1994.apmpdwi.74","DOIUrl":"https://doi.org/10.1364/aoipm.1994.apmpdwi.74","url":null,"abstract":"Analytic calculations have been used to simulate photon density wave interference images of objects within a tissue medium. Various source-detector geometries are examined.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"10 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":"117148202","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}

{"title":"Photoacoustic Imaging of Objects Hidden in Random Scattering Media","authors":"S. Gayen, R. Alfano, C. Penney","doi":"10.1364/aoipm.1996.pi322","DOIUrl":"https://doi.org/10.1364/aoipm.1996.pi322","url":null,"abstract":"Absorption of amplitude-modulated, continuous-wave 800-nm light by a black silicon-rubber ball located inside a highly-scattering medium, such as Intralipid suspensions and chicken breast tissue, generated ultrasound at the modulation frequency. The characteristics of this photoacoustic signal was studied with a focused ultrasound transducer. A one-dimensional image of the object was obtained by scanning it across the irradiating laser beam and monitoring the resulting photoacoustic signal.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"14 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":"133823307","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}

{"title":"Coregistration of Images From Diffusive Wave with Other Imaging Modalities to Enhance Optical Specificity","authors":"V. Ntziachristos, M. A. O'Leary, B. Chance, A. Yodh","doi":"10.1364/aoipm.1996.mt164","DOIUrl":"https://doi.org/10.1364/aoipm.1996.mt164","url":null,"abstract":"We propose an algorithm that combines the spatial resolution available from other imaging modalities, such as MRI, X-ray CT or ultrasound, with the specificity of optical tomography. The algorithm reduces the complexity of the inverse problem, and thus the number of measurements necessary for an accurate reconstruction. We describe the underlying theory and present simulation and experimental results.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"25 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":"123445422","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}

{"title":"Early Arriving Transmitted Photon Intensity through Tissues","authors":"Feng Liu, K. Yoo, R. Alfano","doi":"10.1364/aoipm.1994.trbsdi.170","DOIUrl":"https://doi.org/10.1364/aoipm.1994.trbsdi.170","url":null,"abstract":"The intensity of transmitted ultrashort laser pulses through thick biological tissue within various arriving time windows were studied. It was found that intensity of the early arriving photons decay exponentially with a factor ≈z/l\u0000 t\u0000 , which decay much slower than the first arriving ballistic photons (z/l\u0000 s\u0000 ), where z, l\u0000 t\u0000 , and l\u0000 s\u0000 is thickness, transport mean free path, and scattering mean length of the medium, respectively. This results show that by using near infrared ultrashort laser pulses there may be enough early arriving photons to be used to image through a thick tissue.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"1 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":"123817323","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}

{"title":"Electro-Optical Scanner Using Phased Array Optical Systems","authors":"Shuoming Zhou, Chunhua Xie, Shiyin Zhao, Hanli Liu, Libo He, S. Nioka, B. Chance","doi":"10.1364/aoipm.1996.mt130","DOIUrl":"https://doi.org/10.1364/aoipm.1996.mt130","url":null,"abstract":"The problem of obtaining the precise localization of a hidden absorber in a highly scattering medium of large dimension has confronted the scientific community for a number of years. Optical methods can also use contrast agents and can identify a line from the tissue surface, including the localized contrast agent and hence the tumor. Localization of absorbers/fluorochromes deep within a highly scattering large body of tissue such as the human breast can be effected most precisely by photon diffusive waves (Yodh, physical Review) that are not only amplitude modulated in the MHz region. If they consist of paired sources or detector, in-phase and anti-phase signal can be obtained to establish a null plane (Ref 1,2,3). Such a null plane is highly sensitive to perturbations by extremely small objects, of the order of the size of 70 microliters volume and containing as little as 20 picamole of an absorber. The null plane afforded by the in phase and out of phase cancellation diffusive wave is extremely narrow, and displacements of the array with respect to the hidden absorber of a fraction of a millimeter can be detected. Previous work has shown that the multiple source array consisting of portion of laser diode modulated at 200Mhz (50Mhz) RF signal 180 degree out of phase with the rest of the array gives a sharp phase transition and amplitude null plane. This plane provides a sensitive way for the detection of heterogeneity, and thereby may be used for the localization of small tumors within the human tissue. In order to enlarge the search field for phased array, the amplitude of the RF(200Mhz or 50 MHz) is modulated' by a second lower frequency signal(60 Hz),the phase transition plane moves back and forth in the certain region at the lower frequency. That is the principle of electronic scanning of the phased array. With this technology, we can make a real-time display of the line sight, which can goide the needle to the tumor in the surgeon's biopsy operation. In this paper, we will present the work for the localization of object in media using the phased array scanning.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"269 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":"126962046","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}

{"title":"Sensitivity of Boundary Walls in Photon Migration and Optical Imaging","authors":"B. Das, Feng Liu, R. Alfano","doi":"10.1364/aoipm.1996.pmst41","DOIUrl":"https://doi.org/10.1364/aoipm.1996.pmst41","url":null,"abstract":"Time-resolved light scattering measurements around a cell containing intrahpid suspension were performed with transparent, absorbing, reflecting and water boundaries. In case of the reflecting boundary walls the collection of early light as well as diffuse signal was highly enhanced. When an absorber was introduced into the scattering medium the relative change in intensity profiles was found to be maximum for the reflecting walls suggesting that such a choice of boundary may be used to improve time-resolved shadowgrams as well inverse image reconstruction.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"46 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":"115937647","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}

{"title":"Source Estimation in Inverse Radiative Transfer Problems","authors":"N. Mccormick","doi":"10.1364/aoipm.1994.ncpdir.207","DOIUrl":"https://doi.org/10.1364/aoipm.1994.ncpdir.207","url":null,"abstract":"An inverse diffusion algorithm is proposed for estimating the spatial dependence of a fluorescent source from time-independent, directionally-integrated radiance measurements outside a medium.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"90 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":"115665238","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}

{"title":"Spatial and temporal analysis of human motor activity using noninvasive optical topography","authors":"A. Maki, Y. Yamashita, Yoshitoshi Ito, E. Watanabe, H. Koizumi","doi":"10.1364/aoipm.1996.di357","DOIUrl":"https://doi.org/10.1364/aoipm.1996.di357","url":null,"abstract":"To noninvasively observe the spatiotemporal hemodynamic changes in the cortex that are associated with human cortical activity, we have recently proposed a novel cortical imaging method: noninvasive optical topography (OT). Using OT, which is based on spectroscopic reflection measurement of near-infrared light, we can visualize the changes in the oxygenation states of the cortex. By simulating regional absorption changes in a highly scattering medium using Monte Carlo method, we have determined that linear-signal processing can be used for OT. Furthermore, we have developed a 12-channel OT system and measured the hemodynamic changes around the central sulcus induced by finger movement. The changes caused by contralateral (right) finger movement were found to be significantly different than those due to ipsilateral (left) finger movement.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"3 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":"125518199","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}

{"title":"Statistical Properties of Waves Propagating in a Random Environment","authors":"G. Cwilich","doi":"10.1364/aoipm.1994.wpl.7","DOIUrl":"https://doi.org/10.1364/aoipm.1994.wpl.7","url":null,"abstract":"A diagrammatic approach to evaluate the statistics of the wave intensity in the coherent propagation of light in a random medium is considered; I describe a technique to investigate the underlying random walks by mapping them into spin systems.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"100 6 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":"122883541","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}

{"title":"Angular Dependence of The Intensity Temporal Profiles of Scattered Pulses in Diffusive Regime","authors":"M. Zevallos, F. Liu, B. Das, A. Y. Polishchuck, R. Alfano","doi":"10.1364/aoipm.1996.pmst21","DOIUrl":"https://doi.org/10.1364/aoipm.1996.pmst21","url":null,"abstract":"In this paper, the angular dependence of intensity temporal profiles for three sample media of different scatterer size are described. Detection angles around a fixed point are varied. Similar detection points in each media have been chosen along two directions: forward - along the light source launching direction, x-axis; and lateral or perpendicular direction, y-axis, for comparison. Measurements show the existence of a strong angular dependence of light traveling in a highly scattering media even for distances as large as 20 transport mean free path. More light is observed in the forward direction than in the lateral direction. The strong angular and spatial dependence indicates the existence of an anisotropic behavior of photons from the source directionality. To describe the high degree of anisotropy of photon migration in the medium, two new anisotropy parameters are introduced.","PeriodicalId":368664,"journal":{"name":"Advances in Optical Imaging and Photon Migration","volume":"157 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":"115156294","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}