Deep-tissue focal fluorescence imaging with digitally time-reversed ultrasound-encoded light

Fluorescence imaging is one of the most important research tools in biomedical sciences. However, scattering of light severely impedes imaging of thick biological samples beyond the ballistic regime. Here we directly show focusing and high-resolution fluorescence imaging deep inside biological tissues by digitally time-reversing ultrasound-tagged light with high optical gain (~5×105). We confirm the presence of a time-reversed optical focus along with a diffuse background—a corollary of partial phase conjugation—and develop an approach for dynamic background cancellation. To illustrate the potential of our method, we image complex fluorescent objects and tumour microtissues at an unprecedented depth of 2.5 mm in biological tissues at a lateral resolution of 36 μm×52 μm and an axial resolution of 657 μm. Our results set the stage for a range of deep-tissue imaging applications in biomedical research and medical diagnostics.

[1]  E. Leith,et al.  Holographic Imagery Through Diffusing Media , 1966 .

[2]  Joseph W. Goodman,et al.  WAVEFRONT‐RECONSTRUCTION IMAGING THROUGH RANDOM MEDIA , 1966 .

[3]  Amnon Yariv,et al.  Phase conjugate optics and real time holography (A) , 1978 .

[4]  F Dunn,et al.  Ultrasonic absorption and attenuation in mammalian tissues. , 1979, Ultrasound in medicine & biology.

[5]  J. Feinberg,et al.  Phase-conjugating mirror with continuous-wave gain. , 1980, Optics letters.

[6]  Theo T. Tschudi,et al.  Image amplification by two- and four-wave mixing in BaTiO 3 photorefractive crystals , 1986 .

[7]  A. Welch,et al.  A review of the optical properties of biological tissues , 1990 .

[8]  Pochi Yeh,et al.  Partial phase conjugation, fidelity, and reciprocity , 1994 .

[9]  A. Gaeta,et al.  High‐reflectivity, wide‐bandwidth optical phase conjugation via four‐wave mixing in potassium vapor , 1996 .

[10]  G. Ripandelli,et al.  Optical coherence tomography. , 1998, Seminars in ophthalmology.

[11]  G. Mahan,et al.  Ultrasonic tagging of light: theory. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[12]  K. Beningo,et al.  Fc-receptor-mediated phagocytosis is regulated by mechanical properties of the target. , 2002, Journal of cell science.

[13]  Bruno Sfez,et al.  In vivo demonstration of the ultrasound-modulated light technique. , 2003, Journal of the Optical Society of America. A, Optics, image science, and vision.

[14]  Martin Fussenegger,et al.  Method for generation of homogeneous multicellular tumor spheroids applicable to a wide variety of cell types. , 2003, Biotechnology and bioengineering.

[15]  Vasilis Ntziachristos,et al.  Looking and listening to light: the evolution of whole-body photonic imaging , 2005, Nature Biotechnology.

[16]  W. Denk,et al.  Deep tissue two-photon microscopy , 2005, Nature Methods.

[17]  Steven M. Jones,et al.  Adaptive-optics optical coherence tomography for high-resolution and high-speed 3 D retinal in vivo imaging , 2005 .

[18]  A. Boccara,et al.  Pulsed acousto-optic imaging in dynamic scattering media with heterodyne parallel speckle detection. , 2005, Optics letters.

[19]  J. Mertz,et al.  Rejection of two-photon fluorescence background in thick tissue by differential aberration imaging. , 2006, Optics express.

[20]  A. Mosk,et al.  Focusing coherent light through opaque strongly scattering media. , 2007, Optics letters.

[21]  R. Niessner,et al.  Acoustical properties of selected tissue phantom materials for ultrasound imaging , 2007, Physics in medicine and biology.

[22]  D. Psaltis,et al.  OPTICAL PHASE CONJUGATION FOR TURBIDITY SUPPRESSION IN BIOLOGICAL SAMPLES. , 2008, Nature photonics.

[23]  Sri-Rajasekhar Kothapalli,et al.  Ultrasound-modulated optical microscopy. , 2008, Journal of biomedical optics.

[24]  J Mertz,et al.  Enhanced background rejection in thick tissue with differential-aberration two-photon microscopy. , 2008, Biophysical journal.

[25]  Ton van Leeuwen,et al.  Review of laser speckle contrast techniques for visualizing tissue perfusion , 2008, Lasers in Medical Science.

[26]  Youzhi Li,et al.  Detection of ultrasound-modulated diffuse photons using spectral-hole burning. , 2008, Optics express.

[27]  A. Mosk,et al.  Universal optimal transmission of light through disordered materials. , 2008, Physical review letters.

[28]  I. Vellekoop.  Controlling the propagation of light in disordered scattering media , 2008, 0807.1087.

[29]  G. Roosen,et al.  Detection of the tagged or untagged photons in acousto-optic imaging of thick highly scattering media by photorefractive adaptive holography , 2008, The European physical journal. E, Soft matter.

[30]  P. Chaumet,et al.  Isotropic diffraction-limited focusing using a single objective lens. , 2010, Physical review letters.

[31]  A. Mosk,et al.  Exploiting disorder for perfect focusing , 2009, 0910.0873.

[32]  Changhuei Yang,et al.  An in vivo study of turbidity suppression by optical phase conjugation (TSOPC) on rabbit ear , 2009, Optics express.

[33]  V. Ntziachristos.  Going deeper than microscopy: the optical imaging frontier in biology , 2010, Nature Methods.

[34]  Sylvain Gigan,et al.  Image transmission through an opaque material. , 2010, Nature communications.

[35]  Changhuei Yang,et al.  Implementation of a digital optical phase conjugation system and its application to study the robustness of turbidity suppression by phase conjugation , 2010, Optics express.

[36]  Ivo M Vellekoop,et al.  Turbidity suppression from the ballistic to the diffusive regime in biological tissues using optical phase conjugation. , 2010, Journal of biomedical optics.

[37]  Demetri Psaltis,et al.  Digital phase conjugation of second harmonic radiation emitted by nanoparticles in turbid media. , 2010, Optics express.

[38]  I. Ial,et al.  Nature Communications , 2010, Nature Cell Biology.

[39]  Lihong V. Wang,et al.  Time-reversed ultrasonically encoded optical focusing into scattering media , 2010, Nature photonics.

[40]  S. Gigan,et al.  Spatio-temporal focusing of an ultrafast pulse through a multiply scattering medium. , 2011, Nature communications.

[41]  Puxiang Lai,et al.  Time-reversed ultrasonically encoded optical focusing into tissue-mimicking media with thickness up to 70 mean free paths. , 2011, Journal of biomedical optics.

[42]  E. G. van Putten,et al.  Scattering lens resolves sub-100 nm structures with visible light. , 2011, Physical review letters.

[43]  F. Jaffer,et al.  Intravascular laser speckle imaging catheter for the mechanical evaluation of the arterial wall. , 2011, Journal of biomedical optics.

[44]  O. Katz,et al.  Focusing and compression of ultrashort pulses through scattering media , 2010, 1012.0413.

[45]  Puxiang Lai,et al.  Reflection-mode time-reversed ultrasonically encoded optical focusing into turbid media. , 2011, Journal of biomedical optics.

[46]  M. Kasper,et al.  Adaptive Optics for Astronomy , 2012, 1201.5741.

[47]  D. Conkey,et al.  High-speed scattering medium characterization with application to focusing light through turbid media. , 2012, Optics express.