Complete-angle projection diffuse optical tomography by use of early photons

Turner, Gordon M.; Zacharakis, Giannis; Soubret, Antoine; Ripoll, Jorge; Ntziachristos, Vasilis

doi:10.1364/ol.30.000409

Cited by 88 publications

(67 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 and is capable of collecting photon fields propagating through tissue over 360°projections in a time-gated mode. The resolution improvement of this implementation over approaches using light of constant intensity has been studied with absorbing phantoms embedded in diffusive media by using an earlier system prototype (15,16) operating in attenuation mode. Mice were placed into the imaging chamber inside a custom-made cylindrical holder consisting of 2 carbonfiber tubes that supported the upper and lower body, connected to each other with 2 carbon fiber rods to allow clear viewing of the animal's torso (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Early photons have been used previously in planar transillumination studies of breast tissue samples (9,10). The use of early photons in combination with theoretical models of early-photon propagation have also been considered in the past and yielded systems with the ability to localize relatively simple objects such as 1 or 2 absorbing or fluorescent spheres embedded in a homogenous scattering fluid (13,14) or, as in our previous work, complex shaped absorbing optical phantoms (15,16). These methods, however, were never extended to in vivo imaging and consequently they have not been shown to be biologically useful.…”

mentioning

confidence: 93%

“…To develop a next-generation optical tomographic method that can selectively reduce the effects of tissue scattering to improve imaging accuracy, we developed a system to use early arriving photons, that is, photons emitted from an ultrafast laser source (i.e., pulse width Ͻ1 ps) that propagate through tissue and are the first to arrive at a time-gated detector a distance away from the source (9)(10)(11)(12)(13)(14)(15)(16). The scattering of these early photons is strongly biased in the forward direction and correspondingly they experience a lower number of total scattering events.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Early photon tomography allows fluorescence detection of lung carcinomas and disease progression in mice in vivo

Niedre

Kleine

Aikawa

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

142

112

View full text Add to dashboard Cite

Imaging of targeted fluorescent probes offers significant advantages for investigating disease and tissue function in animal models in vivo. Conversely, macroscopic tomographic imaging is challenging because of the high scatter of light in biological tissue and the ill-posed nature of the reconstruction mathematics. In this work, we use the earliest-transmitted photons through Lewis Lung Carcinoma bearing mice, thereby dramatically reducing the effect of tissue scattering. By using a fluorescent probe sensitive to cysteine proteases, the method yielded outstanding imaging performance compared with conventional approaches. Accurate visualization of biochemical abnormalities was achieved, not only in the primary tumor, but also in the surrounding tissue related to cancer progression and inflammatory response at the organ level. These findings were confirmed histologically and with ex vivo fluorescence microscopy. The imaging fidelity demonstrated underscores a method that can use a wide range of fluorescent probes to accurately visualize cellular-and molecular-level events in whole animals in vivo. (5)] or identifying proteins and molecular pathways of development, function, and disease in vivo. Further enhanced by sensing of spectrally separated fluorescent molecules, fluorescence microscopy currently offers unparalleled insights in the study of cellular and protein interactions. In principle, fluorescence technology could be similarly used to study normal and diseased tissues at the whole-organ and live-animal level. However, there remain significant challenges in imaging beyond a few hundred micrometers in depth because of the high degree of light scatter in tissues, which arises from photon interactions with cellular membranes and organelles. Currently, fluorescence macroscopic imaging is largely performed by illuminating tissue at the fluorochrome's excitation wavelength and detecting the emission from within the animal's body by using appropriate spectral filters. Photographic and planar-fluorescence-imaging implementations of this approach offer only 2-dimensional views and largely qualitative data, because they do not consider the nonlinear relation of photon strength to lesion depth and tissue optical properties. In response, tomographic approaches have been developed to overcome the limitations of these methods (6-8). Optical tomography utilizes multiprojection measurements and physical models of photon propagation to quantitatively retrieve fluorochrome biodistribution in tissues. However, the physical limits of imaging performance of current tomographic implementations ultimately depend on the tissue optical properties-primarily scattering-which leads to a highly ill-posed (i.e., inaccurate) inverse problem that reduces the spatial resolution and yields images that are highly dependent on the particulars of the reconstruction algorithm used.To develop a next-generation optical tomographic method that can selectively reduce the effects of tissue scattering to improve imaging accuracy, we developed a sy...

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 93%

mentioning

confidence: 99%

See 1 more Smart Citation

Early photon tomography allows fluorescence detection of lung carcinomas and disease progression in mice in vivo

Niedre

Kleine

Aikawa

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

142

112

View full text Add to dashboard Cite

show abstract

“…23 Turner et al used a CCD camera to measure early photons in a DOT imaging system. 24 In this study, we used an electron multiplying CCD (EMCCD) camera to measure light intensity on the breast surface in a transmission mode.…”

Section: Introductionmentioning

confidence: 99%

Diffuse optical tomography for breast cancer imaging guided by computed tomography: A feasibility study

Baikejiang

Zhang

2017

XST

View full text Add to dashboard Cite

Abstract. Diffuse optical tomography (DOT) has attracted attentions in the last two decades due to its intrinsic sensitivity in imaging chromophores of tissues such as hemoglobin, water, and lipid. However, DOT has not been clinically accepted yet due to its low spatial resolution caused by strong optical scattering in tissues. Structural guidance provided by an anatomical imaging modality enhances the DOT imaging substantially. Here, we propose a computed tomography (CT) guided multispectral DOT imaging system for breast cancer imaging. To validate its feasibility, we have built a prototype DOT imaging system which consists of a laser at the wavelength of 650 nm and an electron multiplying charge coupled device (EMCCD) camera. We have validated the CT guided DOT reconstruction algorithms with numerical simulations and phantom experiments, in which different imaging setup parameters, such as projection number of measurements and width of measurement patch, have been investigated. Our results indicate that an air-cooling EMCCD camera is good enough for the transmission mode DOT imaging. We have also found that measurements at six angular projections are sufficient for DOT to reconstruct the optical targets with 2 and 4 times absorption contrast when the CT guidance is applied. Finally, we have described our future research plan on integration of a multispectral DOT imaging system into a breast CT scanner.

show abstract

“…[1][2][3][4] Broad efforts to develop these strategies for tissue diagnosis and characterization have included exploiting novel biochemical probes, engineering new detection techniques, improving image recovery methods, [5][6][7][8] and coupling luminescence detectors to standard imaging systems. 9,10 Extracting meaningful spectroscopic measurements or accurate images of the luminescent activity in tissue requires accurate light transport modeling, which, through substantial growth since the early 1990s, 11 has become fairly mature field of research.…”

Section: Introductionmentioning

confidence: 99%

Spectral distortion in diffuse molecular luminescence tomography in turbid media

Davis

Pogue

Tuttle

et al. 2009

Journal of Applied Physics

View full text Add to dashboard Cite

The influence of tissue optical properties on the shape of near-infrared ͑NIR͒ fluorescence emission spectra propagating through multiple centimeters of tissue-like media was investigated. Fluorescence emission spectra measured from 6 cm homogeneous tissue-simulating phantoms show dramatic spectral distortion which results in emission peak shifts of up to 60 nm in wavelength. Measured spectral shapes are highly dependent on the photon path length and the scattered photon field in the NIR amplifies the wavelength-dependent absorption of the fluorescence spectra. Simulations of the peak propagation using diffusion modeling describe the experimental observations and confirm the path length dependence of fluorescence emission spectra. Spectral changes are largest for long path length measurements and thus will be most important in human tomography studies in the NIR. Spectrally resolved detection strategies are required to detect and interpret these effects which may otherwise produce erroneous intensity measurements. This observed phenomenon is analogous to beam hardening in x-ray tomography, which can lead to image artifacts without appropriate compensation. The peak shift toward longer wavelengths, and therefore lower energy photons, observed for NIR luminescent signals propagating through tissue may readily be described as a beam softening phenomenon.

show abstract

Complete-angle projection diffuse optical tomography by use of early photons

Cited by 88 publications

References 15 publications

Early photon tomography allows fluorescence detection of lung carcinomas and disease progression in mice in vivo

Early photon tomography allows fluorescence detection of lung carcinomas and disease progression in mice in vivo

Diffuse optical tomography for breast cancer imaging guided by computed tomography: A feasibility study

Spectral distortion in diffuse molecular luminescence tomography in turbid media

Contact Info

Product

Resources

About