Abstract

A fiber-based reflectance imaging system was constructed to produce in vivo absorption spectroscopic images of biological tissues with diffuse light in the cw domain. The principal part of this system is the 783-channel fiber probe, composed of 253 illumination fibers and 530 detection fibers distributed in a 20×20mm square region. During illumination with the 253 illumination fibers, diffuse reflected lights are collected by the 530 detection fibers and recorded simultaneously as an image with an electron multiplying CCD camera for fast data acquisition. After signal acquisition, a diffuse reflectance image was reconstructed by applying the spectral normalization method we devised. To test the applicability of the spectral normalization, we conducted two phantom experiments with chicken breast tissue and white Delrin resin by using animal blood as an optical inhomogeneity. In the Delrin phantom experiment, we present images produced by two methods, spectral normalization and reference signal normalization, along with a comparison of the two. To show the feasibility of our system for biomedical applications, we took images of a human vein in vivo with the spectral normalization method.

© 2007 Optical Society of America

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References

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  1. A. Garcia-Uribe, N. Kehtarnavaz, G. Marquez, V. Prieto, M. Duvic, and L.-H Wang, "Skin cancer detection by spectroscopic oblique-incidence reflectometry: classification and physiological origins," Appl. Opt. 43, 2643-2650 (2004).
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    [CrossRef] [PubMed]
  19. L. Wang, P. P. Ho, C. Liu, G. Zhang, and R. R. Alfano, "Ballistic 2-D imaging through scattering walls using an ultrafast optical Kerr gate," Science 253, 769-771 (1991).
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
  25. S. Feng, F. Zeng, and B. Chance, "Monte Carlo simulations of photon migration path distributions in multiple scattering media," Proc. SPIE 1888, 78-97 (1993).
    [CrossRef]
  26. A. N. Bashkatov, E. A. Genina, V. I. Kochubey, and V. V. Tuchin, "Optical properties of human skin, subcutaneous and mucous tissues in the wavelength range from 400 to 2000 nm," J. Phys. D 38, 2543-2555 (2005).
    [CrossRef]
  27. A. A. Stratonnikov and V. B. Loschenov, "Evaluation of blood oxygen saturation in vivo from diffuse reflectance spectra," J. Biomed. Opt. 6, 457-467 (2001).
    [CrossRef] [PubMed]
  28. K. Uludag, M. Kohl, J. Steinbrink, H. Obrig, and A. Villringer, "Cross-talk in the Lambert-Beer calculation from near-infrared wavelengths estimated by Monte Carlo simulations," J. Biomed. Opt. 7, 51-59 (2002).
    [CrossRef] [PubMed]
  29. S. Prahl, "Optical absorption of hemoglobin," http://omlc.ogi.edu/spectra/hemoglobin.
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    [CrossRef] [PubMed]
  31. G. Marquez, L. V. Wang, S.-P. Lin, J. A., Schwarts, and S. L. Thomsen, "Anisotropy in the absorption and scattering spectra of chicken breast tissue," Appl. Opt. 37, 798-804 (1998).
    [CrossRef]
  32. W. Cong and G. Wang, "Boundary integral method for bioluminescence tomography," J. Biomed. Opt. 11, 020503 (2006).
    [CrossRef] [PubMed]

2006

N. Subhash, J. R. Mallia, S. S. Thomas, A. Mathews, P. Sebastian, and J. Madhavan, "Oral cancer detection using diffuse reflectance spectral ratio R540/R575 of oxygenated hemoglobin bands," J. Biomed. Opt. 11, 014018 (2006).
[CrossRef] [PubMed]

A. Cerussi, N. Shah, D. Hsiang, A. Durkin, J. Butler, and B. J. Tromberg, "in vivo absorption, scattering, and physiologic properties of 58 malignant breast tumors determined by broadband diffuse optical spectroscopy," J. Biomed. Opt. 11, 044005 (2006).
[CrossRef] [PubMed]

M. A. Franceschini, D. K. Joseph, T. J. Huppert, S. G. Diamond, and D. A. Boas, "Diffuse optical imaging of the whole head," J. Biomed. Opt. 11, 054007 (2006).
[CrossRef] [PubMed]

J. Selb, D. K. Joseph, and D. A. Boas, "Time-gated optical system for depth-resolved functional brain imaging," J. Biomed. Opt. 11, 044008 (2006).
[CrossRef] [PubMed]

W. Cong and G. Wang, "Boundary integral method for bioluminescence tomography," J. Biomed. Opt. 11, 020503 (2006).
[CrossRef] [PubMed]

2005

A. N. Bashkatov, E. A. Genina, V. I. Kochubey, and V. V. Tuchin, "Optical properties of human skin, subcutaneous and mucous tissues in the wavelength range from 400 to 2000 nm," J. Phys. D 38, 2543-2555 (2005).
[CrossRef]

V. Ntziachristos, J. Ripoll, L.-H. Wang, and R. Weissleder, "Looking and listening to light: the revolution of photonic imaging," Nat. Biotechnol. 23, 313-320 (2005).
[CrossRef] [PubMed]

G. Yu, T. Durduran, G. Lech, C. Zhou, B. Chance, E. R. Mohler III, and A. G. Yodh, "Time-dependent blood flow and oxygenation in human skeletal muscles measured with noninvasive near-infrared diffuse optical spectroscopies," J. Biomed. Opt. 10, 024027 (2005).
[CrossRef] [PubMed]

2004

A. Garcia-Uribe, N. Kehtarnavaz, G. Marquez, V. Prieto, M. Duvic, and L.-H Wang, "Skin cancer detection by spectroscopic oblique-incidence reflectometry: classification and physiological origins," Appl. Opt. 43, 2643-2650 (2004).
[CrossRef] [PubMed]

J. H. Choi, M. Wolf, V. Toronov, U. Wolf, C. Polzonetti, D. Hueber, L. P. Safonova, R. Gupta, A. Michalos, W. Mantulin, and E. Gratton, "Noninvasive determination of the optical properties of adult brain: near-infrared spectroscopy approach," J. Biomed. Opt. 9, 221-229 (2004).
[CrossRef] [PubMed]

2003

A. Godavarty, M. J. Eppstein, C. Zhang, S. Theru, A. B. Thompson, M. Gurfinkel, and E. M. Sevic-Muraca, "Fluorescence-enhanced optical imaging in large tissue volumes using a gain modulated ICCD camera," Phys. Med. Biol. 48, 1701-1720 (2003).
[CrossRef] [PubMed]

E. Graves, J. Ripoll, R. Weissleder, and V. Ntziachristos, "Submillimeter resolution fluorescence molecular imaging system for small animal imaging," Med. Phys. 30, 901-911 (2003).
[CrossRef] [PubMed]

2002

V. Ntziachristos, "Fluorescence molecular tomography resolves protease activity in vivo," Nat. Med. 8, 757-760 (2002).
[CrossRef] [PubMed]

G. Yoon, A. K. Amerov, K. J. Jeon, and Y. J. Kim, "Determination of glucose concentration in a scattering medium based on selected wavelengths by use of an overtone absorption," Appl. Opt. 41, 1469-1474 (2002).
[CrossRef] [PubMed]

K. Uludag, M. Kohl, J. Steinbrink, H. Obrig, and A. Villringer, "Cross-talk in the Lambert-Beer calculation from near-infrared wavelengths estimated by Monte Carlo simulations," J. Biomed. Opt. 7, 51-59 (2002).
[CrossRef] [PubMed]

2001

A. A. Stratonnikov and V. B. Loschenov, "Evaluation of blood oxygen saturation in vivo from diffuse reflectance spectra," J. Biomed. Opt. 6, 457-467 (2001).
[CrossRef] [PubMed]

1999

W. Cai, "Optical tomographic image reconstruction from ultrafast time-sliced transmission measurements," Appl. Opt. 38, 4237-4246 (1999).
[CrossRef]

R. M. P. Doornbos, R. Lang, M. C. Aalders, F. W. Cross, and H. J. C. M. Sterenborg, "The determination of in vivo human tissue optical properties and absolute chromophore concentrations using spatially resolved steady-state diffuse reflectance spectroscopy," Phys. Med. Biol. 44, 967-981 (1999).
[CrossRef] [PubMed]

1998

R. R. Alfano, S. G. Demos, P. Galland, S. K. Gayen, Y. Guo, P. P. Ho, X. Liang, F. Liu, L. Wang, Q. Z. Wang, and W. B. Wang, "Time-resolved and nonlinear optical imaging for medical applications," Ann. N.Y. Acad. Sci. 838, 14-28 (1998).
[CrossRef] [PubMed]

G. Marquez, L. V. Wang, S.-P. Lin, J. A., Schwarts, and S. L. Thomsen, "Anisotropy in the absorption and scattering spectra of chicken breast tissue," Appl. Opt. 37, 798-804 (1998).
[CrossRef]

1997

1995

M. A. O'Leary, D. A. Boas, B. Chance, and A. G. Yodh, "Experimental images of heterogeneous turbid media by frequency-domain diffusing-photon tomography," Opt. Lett. 20, 426-428 (1995).
[CrossRef] [PubMed]

L.-H. Wang, S. L. Jacques, and L.-Q. Zheng, "MCML-Monte Carlo modeling of photon transport in multilayered tissues," Comput. Methods Programs Biomed. 47, 131-146 (1995).
[CrossRef] [PubMed]

1993

S. Feng, F. Zeng, and B. Chance, "Monte Carlo simulations of photon migration path distributions in multiple scattering media," Proc. SPIE 1888, 78-97 (1993).
[CrossRef]

J. B. Fishkin and E. Gratton, "Propagation of photon-density waves in strongly scattering media containing an absorbing semi-infinite plane bounded by a straight edge," J. Opt. Soc. Am. A 10, 127-140 (1993).
[CrossRef] [PubMed]

1991

L. Wang, P. P. Ho, C. Liu, G. Zhang, and R. R. Alfano, "Ballistic 2-D imaging through scattering walls using an ultrafast optical Kerr gate," Science 253, 769-771 (1991).
[CrossRef] [PubMed]

1989

W. Cui, C. Kumar, and B. Chance, "Experimental study of migration depth for the photons measured at sample surface," Proc. SPIE 1431, 180-189 (1989).
[CrossRef]

M. S. Patterson, B. Chance, and B. C. Wilson, "Time resolved reflectance and transmittance for the noninvasive measurement of tissue optical properties," Appl. Opt. 28, 2331-2336 (1989).
[CrossRef] [PubMed]

Ann. N.Y. Acad. Sci.

R. R. Alfano, S. G. Demos, P. Galland, S. K. Gayen, Y. Guo, P. P. Ho, X. Liang, F. Liu, L. Wang, Q. Z. Wang, and W. B. Wang, "Time-resolved and nonlinear optical imaging for medical applications," Ann. N.Y. Acad. Sci. 838, 14-28 (1998).
[CrossRef] [PubMed]

Appl. Opt.

Comput. Methods Programs Biomed.

L.-H. Wang, S. L. Jacques, and L.-Q. Zheng, "MCML-Monte Carlo modeling of photon transport in multilayered tissues," Comput. Methods Programs Biomed. 47, 131-146 (1995).
[CrossRef] [PubMed]

J. Biomed. Opt.

W. Cong and G. Wang, "Boundary integral method for bioluminescence tomography," J. Biomed. Opt. 11, 020503 (2006).
[CrossRef] [PubMed]

A. A. Stratonnikov and V. B. Loschenov, "Evaluation of blood oxygen saturation in vivo from diffuse reflectance spectra," J. Biomed. Opt. 6, 457-467 (2001).
[CrossRef] [PubMed]

K. Uludag, M. Kohl, J. Steinbrink, H. Obrig, and A. Villringer, "Cross-talk in the Lambert-Beer calculation from near-infrared wavelengths estimated by Monte Carlo simulations," J. Biomed. Opt. 7, 51-59 (2002).
[CrossRef] [PubMed]

J. Selb, D. K. Joseph, and D. A. Boas, "Time-gated optical system for depth-resolved functional brain imaging," J. Biomed. Opt. 11, 044008 (2006).
[CrossRef] [PubMed]

J. H. Choi, M. Wolf, V. Toronov, U. Wolf, C. Polzonetti, D. Hueber, L. P. Safonova, R. Gupta, A. Michalos, W. Mantulin, and E. Gratton, "Noninvasive determination of the optical properties of adult brain: near-infrared spectroscopy approach," J. Biomed. Opt. 9, 221-229 (2004).
[CrossRef] [PubMed]

N. Subhash, J. R. Mallia, S. S. Thomas, A. Mathews, P. Sebastian, and J. Madhavan, "Oral cancer detection using diffuse reflectance spectral ratio R540/R575 of oxygenated hemoglobin bands," J. Biomed. Opt. 11, 014018 (2006).
[CrossRef] [PubMed]

G. Yu, T. Durduran, G. Lech, C. Zhou, B. Chance, E. R. Mohler III, and A. G. Yodh, "Time-dependent blood flow and oxygenation in human skeletal muscles measured with noninvasive near-infrared diffuse optical spectroscopies," J. Biomed. Opt. 10, 024027 (2005).
[CrossRef] [PubMed]

A. Cerussi, N. Shah, D. Hsiang, A. Durkin, J. Butler, and B. J. Tromberg, "in vivo absorption, scattering, and physiologic properties of 58 malignant breast tumors determined by broadband diffuse optical spectroscopy," J. Biomed. Opt. 11, 044005 (2006).
[CrossRef] [PubMed]

M. A. Franceschini, D. K. Joseph, T. J. Huppert, S. G. Diamond, and D. A. Boas, "Diffuse optical imaging of the whole head," J. Biomed. Opt. 11, 054007 (2006).
[CrossRef] [PubMed]

J. Opt. Soc. Am. A

J. Phys. D

A. N. Bashkatov, E. A. Genina, V. I. Kochubey, and V. V. Tuchin, "Optical properties of human skin, subcutaneous and mucous tissues in the wavelength range from 400 to 2000 nm," J. Phys. D 38, 2543-2555 (2005).
[CrossRef]

Med. Phys.

E. Graves, J. Ripoll, R. Weissleder, and V. Ntziachristos, "Submillimeter resolution fluorescence molecular imaging system for small animal imaging," Med. Phys. 30, 901-911 (2003).
[CrossRef] [PubMed]

Nat. Biotechnol.

V. Ntziachristos, J. Ripoll, L.-H. Wang, and R. Weissleder, "Looking and listening to light: the revolution of photonic imaging," Nat. Biotechnol. 23, 313-320 (2005).
[CrossRef] [PubMed]

Nat. Med.

V. Ntziachristos, "Fluorescence molecular tomography resolves protease activity in vivo," Nat. Med. 8, 757-760 (2002).
[CrossRef] [PubMed]

Opt. Lett.

Phys. Med. Biol.

A. Godavarty, M. J. Eppstein, C. Zhang, S. Theru, A. B. Thompson, M. Gurfinkel, and E. M. Sevic-Muraca, "Fluorescence-enhanced optical imaging in large tissue volumes using a gain modulated ICCD camera," Phys. Med. Biol. 48, 1701-1720 (2003).
[CrossRef] [PubMed]

R. M. P. Doornbos, R. Lang, M. C. Aalders, F. W. Cross, and H. J. C. M. Sterenborg, "The determination of in vivo human tissue optical properties and absolute chromophore concentrations using spatially resolved steady-state diffuse reflectance spectroscopy," Phys. Med. Biol. 44, 967-981 (1999).
[CrossRef] [PubMed]

A. Kienle and M. S. Patterson, "Determination of the optical properties of semi-infinite turbid media from frequency-domain reflectance close to the source," Phys. Med. Biol. 42, 1801-1819 (1997).
[CrossRef] [PubMed]

Proc. SPIE

W. Cui, C. Kumar, and B. Chance, "Experimental study of migration depth for the photons measured at sample surface," Proc. SPIE 1431, 180-189 (1989).
[CrossRef]

S. Feng, F. Zeng, and B. Chance, "Monte Carlo simulations of photon migration path distributions in multiple scattering media," Proc. SPIE 1888, 78-97 (1993).
[CrossRef]

Science

L. Wang, P. P. Ho, C. Liu, G. Zhang, and R. R. Alfano, "Ballistic 2-D imaging through scattering walls using an ultrafast optical Kerr gate," Science 253, 769-771 (1991).
[CrossRef] [PubMed]

Other

S. Prahl, "Optical absorption of hemoglobin," http://omlc.ogi.edu/spectra/hemoglobin.

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Figures (8)

Fig. 1
Fig. 1

(Color online) Schematic illustration of the in vivo 783-channel diffuse reflectance imaging system. The illumination and the detection fiber interface are mounted in the lighttight box to prevent background light noise, and the guiding parts of them are jacketed with rubber-coated cloth. The only light source is located outside the measurement room and all the measurements were conducted in dark conditions. For illumination, two different light sources, i.e., a tungsten halogen lamp with filter set and five laser diode (LD) modules with beam expander, were utilized. These were mounted side-by-side on a carrier and were adjustable according to the illumination wavelength. The reference fiber that directly goes to the detection fiber interface from the illumination fiber interface was utilized as reference for the incident light intensity in each measurement.

Fig. 2
Fig. 2

(Color online) Configuration of the 783-channel fiber probe, which is composed of 253 illumination fibers and 530 detection fibers. (a) 253 illumination fibers; (b) 530 detection fibers; (c) the illumination fiber interface, which is the other end of (a), located in lighttight box 1; (d) the detection fiber interface, which is the other end of (b), and is located in lighttight box 2. The CCD camera faces this interface for a signal capture, so a raw data image is similar to this image; (e) the reconstructed fiber position from the analyzed fiber coordinates. It coincides well with the real fiber photograph (f).

Fig. 3
Fig. 3

(Color online) A bloody pork bead was embedded into chicken breast tissue at (a) 2   mm depth, (d) 5   mm depth, and (g) 8   mm depth (in this phantom the pork bead was covered by more turbid chicken breast tissue). The left column was the results from a conventional photograph, but the reflectance images in the middle and right column were reconstructed by using the spectral normalization method, and 575   nm and 670   nm were utilized as IW, respectively. As the pork beads were more deeply embedded into the chicken breast tissue, their contrasts decreased. When the 575   nm was utilized as an IW, i.e., middle column, the contrast of the pork bead was more obvious than when the 670   nm used, i.e., right column. Here, X and Y axes are position-coordinates, the unit is 2   mm , covering 20 × 20   mm region. The coordinate Z is Γ-values ranging from 0.0 to 2.0, while the redundant color code on the right-hand side exhibits the same Γ-value from 0.70 to 1.40.

Fig. 4
Fig. 4

(Color online) The absorption spectroscopic images of pork bead and chicken breast tissue. We measured this data at point A (pork bead region) and at point B (chicken breast tissue region) in Fig. 3(a) by employing the backscattering probe (BSP) system [2]. In this graph, two reflectance curves R(A) and R(B) almost coincide with each other at the longer wavelength region after 700 nm. The reflectance ratio of the pork bead to the chicken breast, i.e., R(A)∕R(B), is lower at 540 nm or 578 nm than at 670 nm.

Fig. 5
Fig. 5

(Color online) (a)–(l) are the reconstructed images of the delrin and blood phantom through spectral normalization by employing an RW of 808   nm . All blood tubes were embedded into the white delrin matrix medium at the same depth ( 2.5   mm ) but the first row's blood concentration was 100% (v∕v), the second 50%, and the third row 25%, respectively. The serial images in each row were produced by changing IWs (from the left column 575, 635, 655, and 685   nm , respectively). The fourth row's images (m)–(o) were produced by spectral normalization with the data acquired from the homogeneous delrin phantom. The panel (p) is the photographic image of one phantom (c-100% and d - 2.5   mm ). Only the plotting condition of the redundant color code on the right-hand side is different from Fig. 3, but the others are the same. The range of the color-code is 0.84–1.18.

Fig. 6
Fig. 6

(Color online) (a)–(o) are the images produced by the reference signal normalization method (i.e., R ( r j , λ IW ) / R RHM ( r j , λ IW ) ) arranged according to the embedded depths (first row: d - 2.5   mm , second row: d - 3.5   mm , and third row: d - 4.5   mm ) of a blood tube (c-100%) into the delrin medium. At each row, we present the contrast change of the blood tube according to the IWs, i.e., 575, 655, 685, 785, and 808   nm , from the left column to the right column. All plotting conditions are the same as in Fig. 5.

Fig. 7
Fig. 7

(Color online) The first row's serial images are in vivo human vein images produced by the spectral normalization process according to the IWs, (a) 635   nm , (b) 655   nm , (c) 685   nm , and (d) 785   nm . The second row's serial images are estimated-artifact images processed by spectral normalization with the simulation data described in Subsection 2F. The third row's serial images are artifact-compensated images of the first row's serial images, respectively, by applying the second row's images to the compensation. All plotting conditions are the same as in Fig. 5.

Fig. 8
Fig. 8

(Color online) The second row's serial images are reconstructed human vein images produced by spectral normalization processing (IW: 685   nm and RW: 808   nm ), with the different angle of fiber positioning consistent with the flowing direction of veins. Each image in the second row corresponds to the photographic images in the first row. Two arrows in each photographic image of the first row represent two ends of a vein. The third row's serial images are artifact-compensated images of the second row's serial images, respectively, with the data of Fig. 7(g). All the plotting conditions are the same as in Fig. 5.

Tables (1)

Tables Icon

Table 1 Data for μ a and μ s Obtained from Ref. [26] Through Personal Communication

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

R ( r j ) = i = 1 253 R ( r i j , μ a , μ s , g , n rel ) ( j = 1 , 2 ,   .   .   .   ,   530 ) ,
μ a ( λ ) = μ abg ( λ ) + ln ( 10 ) [ ε o x ( λ ) C o x + ε d e ( λ ) C d e ] ,
μ a ( λ ) = μ abg ( λ ) + ln ( 10 ) C tot [ ε o x ( λ ) Y + ε d e ( λ ) ( 1 Y ) ] .
Δ μ a ( λ IW ; λ RW ) μ a ( λ IW ) μ a ( λ RW ) = Δ μ abg ( λ ) + ln ( 10 ) C tot [ Δ ε o x ( λ IW ; λ RW ) Y + Δ ε d e ( λ IW ; λ RW ) ( 1 Y ) ] .
Δ μ a ( λ IW ; λ RW ) C tot Δ ε o x ( λ IW ; λ RW ) Y .

Metrics