Abstract

Melanin is the dominant light absorber in retinal pigment epithelium (RPE). The loss of RPE melanin is a sign of ocular senescence and is both a risk factor and a symptom of age-related macular degeneration (AMD). Quantifying the RPE melanin concentration provides insight into the pathological role of RPE in ocular aging and the onset and progression of AMD. The main challenge in accurate quantification of RPE melanin concentration is to distinguish this ten-micrometer-thick cell monolayer from the underlying choroid, which also contains melanin but carries different pathognomonic information. In this work, we investigated a three-dimensional photoacoustic microscopic (PAM) method with high axial resolution, empowered by broad acoustic detection bandwidth, to distinguish RPE from choroid and quantify melanin concentrations in the RPE ex vivo. We first conducted numerical simulation on photoacoustic generation in the RPE, which suggested that a PAM system with at least 100-MHz detection bandwidth provided sufficient axial resolution to distinguish the melanin in RPE from that in choroid. Based on simulation results, we integrated a transparent broadband micro-ring resonator (MRR) based detector in a homebuilt PAM system. We imaged ex vivo RPE-choroid complexes (RCCs) from both porcine and human eyes and quantified the absolute melanin concentrations in the RPE and choroid, respectively. In our study, the measured melanin concentrations were 14.7 mg/mL and 17.0 mg/mL in human and porcine RPE, and 12 mg/mL and 61 mg/mL in human and porcine choroid, respectively. This study suggests that broadband PAM is capable of quantifying the RPE melanin concentration from RCCs ex vivo.

© 2017 Optical Society of America

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References

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    [Crossref] [PubMed]
  3. O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
    [Crossref] [PubMed]
  4. T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
    [Crossref] [PubMed]
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    [PubMed]
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    [PubMed]
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  13. C. Durairaj, J. E. Chastain, and U. B. Kompella, “Intraocular distribution of melanin in human, monkey, rabbit, minipig and dog eyes,” Exp. Eye Res. 98, 23–27 (2012).
    [Crossref] [PubMed]
  14. X. Shu, W. Liu, and H. F. Zhang, “Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy,” J. Biomed. Opt. 20(10), 106005 (2015).
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  15. D. L. Nickla and J. Wallman, “The multifunctional choroid,” Prog. Retin. Eye Res. 29(2), 144–168 (2010).
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    [Crossref] [PubMed]
  18. B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
    [Crossref] [PubMed]
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    [Crossref] [PubMed]
  20. J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
    [Crossref] [PubMed]
  21. J. Yao and L. V. Wang, “Sensitivity of photoacoustic microscopy,” Photoacoustics 2(2), 87–101 (2014).
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  22. L. V. Wang and S. Hu, “Photoacoustic tomography: in vivo imaging from organelles to organs,” Science 335(6075), 1458–1462 (2012).
    [Crossref] [PubMed]
  23. J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
    [Crossref] [PubMed]
  24. J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
    [Crossref] [PubMed]
  25. X. Zhang, H. F. Zhang, C. A. Puliafito, and S. Jiao, “Simultaneous in vivo imaging of melanin and lipofuscin in the retina with photoacoustic ophthalmoscopy and autofluorescence imaging,” J. Biomed. Opt. 16(8), 080504 (2011).
    [Crossref] [PubMed]
  26. B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
    [Crossref]
  27. G. J. Diebold, T. Sun, and M. I. Khan, “Photoacoustic monopole radiation in one, two, and three dimensions,” Phys. Rev. Lett. 67(24), 3384–3387 (1991).
    [Crossref] [PubMed]
  28. J. Riesz, J. Gilmore, and P. Meredith, “Quantitative scattering of melanin solutions,” Biophys. J. 90(11), 4137–4144 (2006).
    [Crossref] [PubMed]
  29. W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
    [PubMed]
  30. S. J. Preece and E. Claridge, “Monte Carlo modelling of the spectral reflectance of the human eye,” Phys. Med. Biol. 47(16), 2863–2877 (2002).
    [Crossref] [PubMed]
  31. H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
    [PubMed]
  32. C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
    [Crossref] [PubMed]
  33. P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
    [Crossref]
  34. S. Jacques, Optical Absorption of Melanin (Oregon Medical Laser Center, 1998).
  35. T. Sarna and R. C. Sealy, “Photoinduced oxygen consumption in melanin systems. Action spectra and quantum yields for eumelanin and synthetic melanin,” Photochem. Photobiol. 39(1), 69–74 (1984).
    [Crossref] [PubMed]
  36. T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
    [Crossref] [PubMed]
  37. M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
    [Crossref] [PubMed]
  38. E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. A. Folwell, D. R. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4(11), 2527–2539 (2013).
    [Crossref] [PubMed]
  39. T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
    [Crossref] [PubMed]
  40. M. Zareba, T. J. Sarna, and J. M. Burke, “The ratio of melanosome to lipofuscin granule number, not lipofuscin content alone, determines the susceptibility of individual RPE cells to lethal photic stress in vitro,” Invest. Ophthalmol. Vis. Sci. 53, 4273 (2012).
  41. S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
    [Crossref] [PubMed]
  42. S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
    [Crossref]

2015 (4)

X. Shu, W. Liu, and H. F. Zhang, “Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy,” J. Biomed. Opt. 20(10), 106005 (2015).
[Crossref] [PubMed]

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
[Crossref] [PubMed]

T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
[Crossref] [PubMed]

B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
[Crossref]

2014 (5)

J. Yao and L. V. Wang, “Sensitivity of photoacoustic microscopy,” Photoacoustics 2(2), 87–101 (2014).
[Crossref] [PubMed]

H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
[PubMed]

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
[Crossref] [PubMed]

S. A. Randolph, “Age-Related Macular Degeneration,” Workplace Health Saf. 62(8), 352(2014).
[Crossref] [PubMed]

2013 (2)

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. A. Folwell, D. R. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4(11), 2527–2539 (2013).
[Crossref] [PubMed]

2012 (4)

B. Baumann, S. O. Baumann, T. Konegger, M. Pircher, E. Götzinger, F. Schlanitz, C. Schütze, H. Sattmann, M. Litschauer, U. Schmidt-Erfurth, and C. K. Hitzenberger, “Polarization sensitive optical coherence tomography of melanin provides intrinsic contrast based on depolarization,” Biomed. Opt. Express 3(7), 1670–1683 (2012).
[Crossref] [PubMed]

M. Zareba, T. J. Sarna, and J. M. Burke, “The ratio of melanosome to lipofuscin granule number, not lipofuscin content alone, determines the susceptibility of individual RPE cells to lethal photic stress in vitro,” Invest. Ophthalmol. Vis. Sci. 53, 4273 (2012).

L. V. Wang and S. Hu, “Photoacoustic tomography: in vivo imaging from organelles to organs,” Science 335(6075), 1458–1462 (2012).
[Crossref] [PubMed]

C. Durairaj, J. E. Chastain, and U. B. Kompella, “Intraocular distribution of melanin in human, monkey, rabbit, minipig and dog eyes,” Exp. Eye Res. 98, 23–27 (2012).
[Crossref] [PubMed]

2011 (1)

X. Zhang, H. F. Zhang, C. A. Puliafito, and S. Jiao, “Simultaneous in vivo imaging of melanin and lipofuscin in the retina with photoacoustic ophthalmoscopy and autofluorescence imaging,” J. Biomed. Opt. 16(8), 080504 (2011).
[Crossref] [PubMed]

2010 (3)

M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
[Crossref] [PubMed]

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
[Crossref] [PubMed]

D. L. Nickla and J. Wallman, “The multifunctional choroid,” Prog. Retin. Eye Res. 29(2), 144–168 (2010).
[Crossref] [PubMed]

2007 (1)

C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
[Crossref] [PubMed]

2006 (4)

C. N. Keilhauer and F. C. Delori, “Near-infrared autofluorescence imaging of the fundus: visualization of ocular melanin,” Invest. Ophthalmol. Vis. Sci. 47(8), 3556–3564 (2006).
[Crossref] [PubMed]

J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
[Crossref] [PubMed]

P. T. de Jong, “Age-related macular degeneration,” N. Engl. J. Med. 355(14), 1474–1485 (2006).
[Crossref] [PubMed]

J. Riesz, J. Gilmore, and P. Meredith, “Quantitative scattering of melanin solutions,” Biophys. J. 90(11), 4137–4144 (2006).
[Crossref] [PubMed]

2005 (3)

B.-L. L. Seagle, K. A. Rezai, Y. Kobori, E. M. Gasyna, K. A. Rezaei, and J. R. Norris., “Melanin photoprotection in the human retinal pigment epithelium and its correlation with light-induced cell apoptosis,” Proc. Natl. Acad. Sci. U.S.A. 102(25), 8978–8983 (2005).
[Crossref] [PubMed]

O. Strauss, “The retinal pigment epithelium in visual function,” Physiol. Rev. 85(3), 845–881 (2005).
[Crossref] [PubMed]

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

2004 (1)

J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
[Crossref] [PubMed]

2003 (1)

T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
[Crossref] [PubMed]

2002 (1)

S. J. Preece and E. Claridge, “Monte Carlo modelling of the spectral reflectance of the human eye,” Phys. Med. Biol. 47(16), 2863–2877 (2002).
[Crossref] [PubMed]

1996 (1)

J. van de Kraats, T. T. Berendschot, and D. van Norren, “The pathways of light measured in fundus reflectometry,” Vision Res. 36(15), 2229–2247 (1996).
[Crossref] [PubMed]

1995 (1)

S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
[Crossref]

1992 (1)

T. Sarna, “Properties and function of the ocular melanin--a photobiophysical view,” J. Photochem. Photobiol. B 12(3), 215–258 (1992).
[Crossref] [PubMed]

1991 (1)

G. J. Diebold, T. Sun, and M. I. Khan, “Photoacoustic monopole radiation in one, two, and three dimensions,” Phys. Rev. Lett. 67(24), 3384–3387 (1991).
[Crossref] [PubMed]

1986 (2)

J. J. Weiter, F. C. Delori, G. L. Wing, and K. A. Fitch, “Retinal pigment epithelial lipofuscin and melanin and choroidal melanin in human eyes,” Invest. Ophthalmol. Vis. Sci. 27(2), 145–152 (1986).
[PubMed]

S. Y. Schmidt and R. D. Peisch, “Melanin concentration in normal human retinal pigment epithelium. Regional variation and age-related reduction,” Invest. Ophthalmol. Vis. Sci. 27(7), 1063–1067 (1986).
[PubMed]

1984 (2)

L. Feeney-Burns, E. S. Hilderbrand, and S. Eldridge, “Aging human RPE: morphometric analysis of macular, equatorial, and peripheral cells,” Invest. Ophthalmol. Vis. Sci. 25(2), 195–200 (1984).
[PubMed]

T. Sarna and R. C. Sealy, “Photoinduced oxygen consumption in melanin systems. Action spectra and quantum yields for eumelanin and synthetic melanin,” Photochem. Photobiol. 39(1), 69–74 (1984).
[Crossref] [PubMed]

1978 (1)

P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
[Crossref]

1962 (1)

W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
[PubMed]

Ablonczy, Z.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

Ach, T.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

Adhyaru, B. B.

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

Aguilar, G.

J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
[Crossref] [PubMed]

Aliprandini, E.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
[Crossref] [PubMed]

Ashkenazi, S.

C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
[Crossref] [PubMed]

Augustin, M.

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
[Crossref] [PubMed]

Baptista, M. S.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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Bauer-Marschallinger, J.

T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
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B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
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B. Baumann, S. O. Baumann, T. Konegger, M. Pircher, E. Götzinger, F. Schlanitz, C. Schütze, H. Sattmann, M. Litschauer, U. Schmidt-Erfurth, and C. K. Hitzenberger, “Polarization sensitive optical coherence tomography of melanin provides intrinsic contrast based on depolarization,” Biomed. Opt. Express 3(7), 1670–1683 (2012).
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Baumann, S. O.

Bentley, M. J.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
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J. van de Kraats, T. T. Berendschot, and D. van Norren, “The pathways of light measured in fundus reflectometry,” Vision Res. 36(15), 2229–2247 (1996).
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T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
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Bowers, C. R.

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
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Buchsbaum, A.

T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
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Burke, J. M.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
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M. Zareba, T. J. Sarna, and J. M. Burke, “The ratio of melanosome to lipofuscin granule number, not lipofuscin content alone, determines the susceptibility of individual RPE cells to lethal photic stress in vitro,” Invest. Ophthalmol. Vis. Sci. 53, 4273 (2012).

T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
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Chan, G.

W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
[PubMed]

Chao, C. Y.

C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
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C. Durairaj, J. E. Chastain, and U. B. Kompella, “Intraocular distribution of melanin in human, monkey, rabbit, minipig and dog eyes,” Exp. Eye Res. 98, 23–27 (2012).
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Chen, R.

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
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Chen, S.

Cheng, C. Y.

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
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Chiarelli-Neto, O.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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Choi, B.

J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
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Chung, M. M.

Claridge, E.

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P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
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Cristofoletti, V.

P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
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Culjat, M. O.

M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
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Curcio, C. A.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
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P. T. de Jong, “Age-related macular degeneration,” N. Engl. J. Med. 355(14), 1474–1485 (2006).
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C. N. Keilhauer and F. C. Delori, “Near-infrared autofluorescence imaging of the fundus: visualization of ocular melanin,” Invest. Ophthalmol. Vis. Sci. 47(8), 3556–3564 (2006).
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J. J. Weiter, F. C. Delori, G. L. Wing, and K. A. Fitch, “Retinal pigment epithelial lipofuscin and melanin and choroidal melanin in human eyes,” Invest. Ophthalmol. Vis. Sci. 27(2), 145–152 (1986).
[PubMed]

Di Mascio, P.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
[Crossref] [PubMed]

Diebold, G. J.

G. J. Diebold, T. Sun, and M. I. Khan, “Photoacoustic monopole radiation in one, two, and three dimensions,” Phys. Rev. Lett. 67(24), 3384–3387 (1991).
[Crossref] [PubMed]

Dong, B.

B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
[Crossref]

H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
[PubMed]

Dubra, A.

Durairaj, C.

C. Durairaj, J. E. Chastain, and U. B. Kompella, “Intraocular distribution of melanin in human, monkey, rabbit, minipig and dog eyes,” Exp. Eye Res. 98, 23–27 (2012).
[Crossref] [PubMed]

Eldridge, S.

L. Feeney-Burns, E. S. Hilderbrand, and S. Eldridge, “Aging human RPE: morphometric analysis of macular, equatorial, and peripheral cells,” Invest. Ophthalmol. Vis. Sci. 25(2), 195–200 (1984).
[PubMed]

Faião-Flores, F.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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Feeney-Burns, L.

L. Feeney-Burns, E. S. Hilderbrand, and S. Eldridge, “Aging human RPE: morphometric analysis of macular, equatorial, and peripheral cells,” Invest. Ophthalmol. Vis. Sci. 25(2), 195–200 (1984).
[PubMed]

Ferreira, A. S.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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Fialová, S.

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
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Fischer, W.

Fitch, K. A.

J. J. Weiter, F. C. Delori, G. L. Wing, and K. A. Fitch, “Retinal pigment epithelial lipofuscin and melanin and choroidal melanin in human eyes,” Invest. Ophthalmol. Vis. Sci. 27(2), 145–152 (1986).
[PubMed]

Folwell, M. A.

Foster, F.

S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
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B.-L. L. Seagle, K. A. Rezai, Y. Kobori, E. M. Gasyna, K. A. Rezaei, and J. R. Norris., “Melanin photoprotection in the human retinal pigment epithelium and its correlation with light-induced cell apoptosis,” Proc. Natl. Acad. Sci. U.S.A. 102(25), 8978–8983 (2005).
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Geeraets, W. J.

W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
[PubMed]

Gerwat, W.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
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J. Riesz, J. Gilmore, and P. Meredith, “Quantitative scattering of melanin solutions,” Biophys. J. 90(11), 4137–4144 (2006).
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B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
[Crossref] [PubMed]

Goldenberg, D.

M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
[Crossref] [PubMed]

Götzinger, E.

Gröger, M.

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
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Guerry, D.

W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
[PubMed]

Guo, L. J.

C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
[Crossref] [PubMed]

Gutierrez, D. B.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

Ham, W. T.

W. J. Geeraets, R. C. Williams, G. Chan, W. T. Ham, D. Guerry, and F. H. Schmidt, “The relative absorption of thermal energy in retina and choroid,” Invest. Ophthalmol. 1, 340–347 (1962).
[PubMed]

Harasiewicz, K.

S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
[Crossref]

Hilderbrand, E. S.

L. Feeney-Burns, E. S. Hilderbrand, and S. Eldridge, “Aging human RPE: morphometric analysis of macular, equatorial, and peripheral cells,” Invest. Ophthalmol. Vis. Sci. 25(2), 195–200 (1984).
[PubMed]

Hitzenberger, C. K.

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
[Crossref] [PubMed]

B. Baumann, S. O. Baumann, T. Konegger, M. Pircher, E. Götzinger, F. Schlanitz, C. Schütze, H. Sattmann, M. Litschauer, U. Schmidt-Erfurth, and C. K. Hitzenberger, “Polarization sensitive optical coherence tomography of melanin provides intrinsic contrast based on depolarization,” Biomed. Opt. Express 3(7), 1670–1683 (2012).
[Crossref] [PubMed]

Hochreiner, A.

T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
[Crossref] [PubMed]

Hong, L.

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

Hu, S.

L. V. Wang and S. Hu, “Photoacoustic tomography: in vivo imaging from organelles to organs,” Science 335(6075), 1458–1462 (2012).
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Huang, S. W.

C. Y. Chao, S. Ashkenazi, S. W. Huang, M. O’Donnell, and L. J. Guo, “High-frequency ultrasound sensors using polymer microring resonators,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 54(5), 957–965 (2007).
[Crossref] [PubMed]

Huisingh, C.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

Ito, M.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

Ito, S.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

Jiao, S.

X. Zhang, H. F. Zhang, C. A. Puliafito, and S. Jiao, “Simultaneous in vivo imaging of melanin and lipofuscin in the retina with photoacoustic ophthalmoscopy and autofluorescence imaging,” J. Biomed. Opt. 16(8), 080504 (2011).
[Crossref] [PubMed]

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
[Crossref] [PubMed]

Keilhauer, C. N.

C. N. Keilhauer and F. C. Delori, “Near-infrared autofluorescence imaging of the fundus: visualization of ocular melanin,” Invest. Ophthalmol. Vis. Sci. 47(8), 3556–3564 (2006).
[Crossref] [PubMed]

Khan, M. I.

G. J. Diebold, T. Sun, and M. I. Khan, “Photoacoustic monopole radiation in one, two, and three dimensions,” Phys. Rev. Lett. 67(24), 3384–3387 (1991).
[Crossref] [PubMed]

Kiyono, A.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

Kobori, Y.

B.-L. L. Seagle, K. A. Rezai, Y. Kobori, E. M. Gasyna, K. A. Rezaei, and J. R. Norris., “Melanin photoprotection in the human retinal pigment epithelium and its correlation with light-induced cell apoptosis,” Proc. Natl. Acad. Sci. U.S.A. 102(25), 8978–8983 (2005).
[Crossref] [PubMed]

Kolbe, L.

S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

Komadina, J.

J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
[Crossref] [PubMed]

Kompella, U. B.

C. Durairaj, J. E. Chastain, and U. B. Kompella, “Intraocular distribution of melanin in human, monkey, rabbit, minipig and dog eyes,” Exp. Eye Res. 98, 23–27 (2012).
[Crossref] [PubMed]

Konegger, T.

Korytowski, W.

T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
[Crossref] [PubMed]

Latchney, L. R.

Leiss-Holzinger, E.

T. Berer, E. Leiss-Holzinger, A. Hochreiner, J. Bauer-Marschallinger, and A. Buchsbaum, “Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing,” J. Biomed. Opt. 20(4), 46013 (2015).
[Crossref] [PubMed]

Li, H.

B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
[Crossref]

H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
[PubMed]

Li, M.-L.

J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
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Litschauer, M.

Liu, T.

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
[Crossref] [PubMed]

Liu, W.

X. Shu, W. Liu, and H. F. Zhang, “Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy,” J. Biomed. Opt. 20(10), 106005 (2015).
[Crossref] [PubMed]

Liu, Y.

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

Maria-Engler, S. S.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
[Crossref] [PubMed]

Martinez, G. R.

O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
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S. Y. Schmidt and R. D. Peisch, “Melanin concentration in normal human retinal pigment epithelium. Regional variation and age-related reduction,” Invest. Ophthalmol. Vis. Sci. 27(7), 1063–1067 (1986).
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J. Riesz, J. Gilmore, and P. Meredith, “Quantitative scattering of melanin solutions,” Biophys. J. 90(11), 4137–4144 (2006).
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P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
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Rózanowska, M.

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M. Zareba, T. J. Sarna, and J. M. Burke, “The ratio of melanosome to lipofuscin granule number, not lipofuscin content alone, determines the susceptibility of individual RPE cells to lethal photic stress in vitro,” Invest. Ophthalmol. Vis. Sci. 53, 4273 (2012).

Sattmann, H.

Schirmer, J.

B. Baumann, J. Schirmer, S. Rauscher, S. Fialová, M. Glösmann, M. Augustin, M. Pircher, M. Gröger, and C. K. Hitzenberger, “Melanin pigmentation in rat eyes: in vivo imaging by polarization-sensitive optical coherence tomography and comparison to histology,” Invest. Ophthalmol. Vis. Sci. 56(12), 7462–7472 (2015).
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Schmidt, F. H.

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S. Y. Schmidt and R. D. Peisch, “Melanin concentration in normal human retinal pigment epithelium. Regional variation and age-related reduction,” Invest. Ophthalmol. Vis. Sci. 27(7), 1063–1067 (1986).
[PubMed]

Schmidt-Erfurth, U.

Schütze, C.

Seagle, B.-L. L.

B.-L. L. Seagle, K. A. Rezai, Y. Kobori, E. M. Gasyna, K. A. Rezaei, and J. R. Norris., “Melanin photoprotection in the human retinal pigment epithelium and its correlation with light-induced cell apoptosis,” Proc. Natl. Acad. Sci. U.S.A. 102(25), 8978–8983 (2005).
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T. Sarna and R. C. Sealy, “Photoinduced oxygen consumption in melanin systems. Action spectra and quantum yields for eumelanin and synthetic melanin,” Photochem. Photobiol. 39(1), 69–74 (1984).
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O. Chiarelli-Neto, A. S. Ferreira, W. K. Martins, C. Pavani, D. Severino, F. Faião-Flores, S. S. Maria-Engler, E. Aliprandini, G. R. Martinez, P. Di Mascio, M. H. Medeiros, and M. S. Baptista, “Melanin photosensitization and the effect of visible light on epithelial cells,” PLoS One 9(11), e113266 (2014).
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X. Shu, W. Liu, and H. F. Zhang, “Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy,” J. Biomed. Opt. 20(10), 106005 (2015).
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J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
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Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
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M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
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S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
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Sloan, K. R.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
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T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
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J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
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B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
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H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
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Tewari, P.

M. O. Culjat, D. Goldenberg, P. Tewari, and R. S. Singh, “A review of tissue substitutes for ultrasound imaging,” Ultrasound Med. Biol. 36(6), 861–873 (2010).
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J. A. Viator, J. Komadina, L. O. Svaasand, G. Aguilar, B. Choi, and J. Stuart Nelson, “A comparative study of photoacoustic and reflectance methods for determination of epidermal melanin content,” J. Invest. Dermatol. 122(6), 1432–1439 (2004).
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S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

Y. Liu, L. Hong, K. Wakamatsu, S. Ito, B. B. Adhyaru, C. Y. Cheng, C. R. Bowers, and J. D. Simon, “Comparisons of the structural and chemical properties of melanosomes isolated from retinal pigment epithelium, iris and choroid of newborn and mature bovine eyes,” Photochem. Photobiol. 81(3), 510–516 (2005).
[Crossref] [PubMed]

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D. L. Nickla and J. Wallman, “The multifunctional choroid,” Prog. Retin. Eye Res. 29(2), 144–168 (2010).
[Crossref] [PubMed]

Wang, J.

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
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J. Yao and L. V. Wang, “Sensitivity of photoacoustic microscopy,” Photoacoustics 2(2), 87–101 (2014).
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[Crossref] [PubMed]

J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
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Williams, R. C.

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S. Ye, K. Harasiewicz, C. Pavlin, and F. Foster, “Ultrasound characterization of normal ocular tissue in the frequency range from 50 MHz to 100 MHz,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 42(1), 8–14 (1995).
[Crossref]

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S. Ito, A. Pilat, W. Gerwat, C. M. Skumatz, M. Ito, A. Kiyono, A. Zadlo, Y. Nakanishi, L. Kolbe, J. M. Burke, T. Sarna, and K. Wakamatsu, “Photoaging of human retinal pigment epithelium is accompanied by oxidative modifications of its eumelanin,” Pigment Cell Melanoma Res. 26(3), 357–366 (2013).
[Crossref] [PubMed]

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T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
[Crossref] [PubMed]

Zareba, M.

M. Zareba, T. J. Sarna, and J. M. Burke, “The ratio of melanosome to lipofuscin granule number, not lipofuscin content alone, determines the susceptibility of individual RPE cells to lethal photic stress in vitro,” Invest. Ophthalmol. Vis. Sci. 53, 4273 (2012).

T. Sarna, J. M. Burke, W. Korytowski, M. Rózanowska, C. M. Skumatz, A. Zaręba, and M. Zaręba, “Loss of melanin from human RPE with aging: possible role of melanin photooxidation,” Exp. Eye Res. 76(1), 89–98 (2003).
[Crossref] [PubMed]

Zhang, H. F.

X. Shu, W. Liu, and H. F. Zhang, “Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy,” J. Biomed. Opt. 20(10), 106005 (2015).
[Crossref] [PubMed]

B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
[Crossref]

H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
[PubMed]

X. Zhang, H. F. Zhang, C. A. Puliafito, and S. Jiao, “Simultaneous in vivo imaging of melanin and lipofuscin in the retina with photoacoustic ophthalmoscopy and autofluorescence imaging,” J. Biomed. Opt. 16(8), 080504 (2011).
[Crossref] [PubMed]

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
[Crossref] [PubMed]

J.-T. Oh, M.-L. Li, H. F. Zhang, K. Maslov, G. Stoica, and L. V. Wang, “Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy,” J. Biomed. Opt. 11(3), 034032 (2006).
[Crossref] [PubMed]

Zhang, K.

Zhang, T.

T. Ach, C. Huisingh, G. McGwin, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, “Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium,” Invest. Ophthalmol. Vis. Sci. 55(8), 4832–4841 (2014).
[Crossref] [PubMed]

Zhang, X.

X. Zhang, H. F. Zhang, C. A. Puliafito, and S. Jiao, “Simultaneous in vivo imaging of melanin and lipofuscin in the retina with photoacoustic ophthalmoscopy and autofluorescence imaging,” J. Biomed. Opt. 16(8), 080504 (2011).
[Crossref] [PubMed]

Zhang, Z.

B. Dong, H. Li, Z. Zhang, K. Zhang, S. Chen, C. Sun, and H. F. Zhang, “Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection,” Optica 2(2), 169–176 (2015).
[Crossref]

H. Li, B. Dong, Z. Zhang, H. F. Zhang, and C. Sun, “A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy,” Sci. Rep. 4, 4496 (2014).
[PubMed]

Zhou, Q.

J. Wang, T. Liu, S. Jiao, R. Chen, Q. Zhou, K. K. Shung, L. V. Wang, and H. F. Zhang, “Saturation effect in functional photoacoustic imaging,” J. Biomed. Opt. 15(2), 021317 (2010).
[Crossref] [PubMed]

Biochim. Biophys. Acta-General Subjects (1)

P. Crippa, V. Cristofoletti, and N. Romeo, “A band model for melanin deduced from optical absorption and photoconductivity experiments,” Biochim. Biophys. Acta-General Subjects 538(1), 164–170 (1978).
[Crossref]

Biomed. Opt. Express (2)

Biophys. J. (1)

J. Riesz, J. Gilmore, and P. Meredith, “Quantitative scattering of melanin solutions,” Biophys. J. 90(11), 4137–4144 (2006).
[Crossref] [PubMed]

Exp. Eye Res. (2)

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Figures (8)

Fig. 1
Fig. 1 (a) Structure of RCC and light illumination. (b) Schematic of optical excitation and PA generation by RCC. (c) Simulated energy deposition profile along the depth direction. E. D.: energy deposition. (d) Simulated PA A-line with 110-MHz acoustic detection bandwidth. Norm. Amp.: normalized amplitude. (e) Simulated PA A-line with 70-MHz acoustic detection bandwidth. In PA simulations, RPE thickness was 10 µm; RPE melanin concentration was 20 mg/mL; choroidal melanin concentration was 60 mg/mL.

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Fig. 2
Fig. 2 (a) Variation of normalized peak amplitudes of RPE (and choroid in cases where axial resolution cannot resolve the boundary between the two layers) PA A-lines with preset RPE melanin concentrations for different acoustic detection bandwidths. M. C.: melanin concentration; choroidal melanin concentration: 15 mg/mL. (b) Variation of relative mean square error with acoustic detection bandwidth if using RPE (and choroid in cases where axial resolution cannot resolve the boundary between the two layers) PA amplitude to estimate RPE melanin concentration. Conditions under different choroidal melanin concentrations were simulated. MSE: mean square error. The relative MSEs were calculated from preset RPE melanin concentration values between 10 mg/mL and 30 mg/mL, which range covers physiological RPE M. C. (c) Variation of choroid to RPE PA signal ratio with choroidal melanin concentrations. Conditions under different RPE melanin concentrations were simulated. Acoustic detection bandwidth: 110 MHz. RPE thickness was 10 µm in all simulations.

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Fig. 3
Fig. 3 PAM experimental system. Relay lenses are omitted in the dashed box. Piezoelectric transducer and MRR transducer were used to detect PA signal from both sides of the sample. MRR: micro-ring resonator; APD: avalanche photodiode.

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Fig. 4
Fig. 4 (a) Melanin extinction coefficients spectrum. Shaded area, standard deviation. Ext. Coef.: extinction coefficient. (b) PA signal amplitude generated by phantoms with controlled melanin concentrations. Error bar: standard deviation.

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Fig. 5
Fig. 5 PA A-lines detected from RCC samples using different ultrasonic detectors. (a) PA A-line of a porcine RCC sample acquired by customized piezoelectric transducer. (b) Amplitude spectrum of the A-line signal in (a). (c) PA A-line of a porcine RCC sample acquired by broadband MRR detector. (d) Amplitude spectrum of the A-line signal in (c). (e) PA A-line of a human RCC sample acquired by broadband MRR detector. (f) Amplitude spectrum of the A-line signal in (e).

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Fig. 6
Fig. 6 PA images of porcine and human RCC. (a) PA image of porcine RCC acquired by customized piezoelectric transducer. (b)-(c) PA image of porcine RCC acquired by broadband MRR detector. (b) Axially segmented porcine RPE. (c) Axially segmented porcine choroid. (a)-(c) are images of the same area on a single sample. (d) PA image of human RCC acquired by customized piezoelectric transducer. (e)-(f) PA image of human RCC acquired by homemade MRR detector. (b) Axially segmented human RPE. (c) Axially segmented human choroid. (d)-(f) are images of the same area on a single sample. Scale bar, 50 µm.

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Fig. 7
Fig. 7 (a) PA B-scan of porcine RCC. (b) PA B-scan of human RCC. RPE cells are visualized on top of choroid tissue. Scale bar, 30 µm.

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Fig. 8
Fig. 8 Comparison of melanin concentration in RPE and choroid between porcine and human samples. M. C.: Melanin concentration. Error bar: standard deviation.

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Equations (4)

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

PA=Γ E dep ,
E dep = μ a ϕ.
PA=Γ C M ε M ϕ=a C M ,
PA=Γ C M ε M ϕ=a C M ,

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