Point spread function measured in human skin using two-photon fluorescence microscopy

The two-photon excitation point spread function (TPE-PSF) has been measured in human skin in vitro in order to examine the optical resolution. This has been done by injecting fluorescent subresolution beads in skin samples using a syringe. The beads were imaged at different depths and the full width at half maximum (FWHM) of the TPE-PSF in the lateral and axial direction were measured from the intensity profile of the emission. The experimentally obtained values of the PSF widths were larger than calculated values. Both the lateral FWHM and the axial FWHM were broadened as a function of depth but the increase was stronger in the axial direction. This indicates that the optical properties of the skin have a more pronounced effect of the resolution in the axial direction.

[1]  W. Webb,et al.  Nonlinear magic: multiphoton microscopy in the biosciences , 2003, Nature Biotechnology.

[2]  H. Gerritsen,et al.  Imaging of optically thick specimen using two‐photon excitation microscopy , 1999, Microscopy research and technique.

[3]  K. Fujita.  [Two-photon laser scanning fluorescence microscopy]. , 2007, Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme.

[4]  Maria Smedh,et al.  Multiphoton laser scanning microscopy on non-melanoma skin cancer: morphologic features for future non-invasive diagnostics. , 2008, The Journal of investigative dermatology.

[5]  Karsten König,et al.  Sensitivity and specificity of multiphoton laser tomography for in vivo and ex vivo diagnosis of malignant melanoma. , 2009, The Journal of investigative dermatology.

[6]  Iris Riemann,et al.  High-resolution multiphoton tomography of human skin with subcellular spatial resolution and picosecond time resolution. , 2003, Journal of biomedical optics.

[7]  H T van der Voort,et al.  Imaging properties in two-photon excitation microscopy and effects of refractive-index mismatch in thick specimens. , 1999, Applied optics.

[8]  Yu Chong,et al.  The mechanical properties of the skin epidermis in relation to targeted gene and drug delivery. , 2007, Biomaterials.

[9]  Maria Smedh,et al.  Lipid cubic phases in topical drug delivery: visualization of skin distribution using two-photon microscopy. , 2008, Journal of controlled release : official journal of the Controlled Release Society.

[10]  Peter Fischer,et al.  Characterization of multiphoton laser scanning device optical parameters for image restoration , 2004, SPIE Photonics Europe.

[11]  B R Masters,et al.  Multiphoton Excitation Microscopy of In Vivo Human Skin: Functional and Morphological Optical Biopsy Based on Three‐Dimensional Imaging, Lifetime Measurements and Fluorescence Spectroscopy a , 1998, Annals of the New York Academy of Sciences.

[12]  B R Masters,et al.  Multiphoton excitation fluorescence microscopy and spectroscopy of in vivo human skin. , 1997, Biophysical journal.

[13]  P. So,et al.  In vitro visualization and quantification of oleic acid induced changes in transdermal transport using two-photon fluorescence microscopy. , 2001, The Journal of investigative dermatology.