Imaging directed photothermolysis through two‐photon absorption demonstrated on mouse skin – a potential novel tool for highly targeted skin treatment. Issue 7 (19th March 2013)

• Record Type: Journal Article
• Authors: Wang, Hequn; Zandi, Soodabeh; Lee, Anthony M.D.; Zhao, Jianhua; Lui, Harvey; McLean, David I.; Zeng, Haishan
• Is Part Of: Journal of biophotonics. Volume 7:Issue 7(2014)
• Page Start: 534
• Page End: 541
• Publication Date: 2013-03-19
• Subjects: Photonics -- Periodicals; Optical materials -- Periodicals; Optics -- Periodicals; Medical instruments and apparatus -- Periodicals; 621.3605
• DOI: 10.1002/jbio.201300016
• Languages: English
• ISSNs: 1864-063X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>One‐photon absorption based traditional laser treatment may not necessarily be selective at the microscopic level, thus could result in un‐intended tissue damage. Our objective is to test whether two‐photon absorption (TPA) could provide highly targeted tissue alteration of specific region of interest without damaging surrounding tissues. TPA based laser treatments (785 nm, 140 fs pulse width, 90 MHz) were performed on <italic>ex vivo</italic> mouse skin using different average power levels and irradiation times. Reflectance confocal microscopy (RCM) and combined second‐harmonic‐generation (SHG) and two‐photon fluorescence (TPF) imaging channels were used to image before, during, and after each laser treatment. The skin was fixed, sectioned and H & E stained after each experiment for histological assessment of tissue alterations and for comparison with the non‐invasive imaging assessments. Localized destruction of dermal fibers was observed without discernible epidermal damage on both RCM and SHG + TPF images for all the experiments. RCM and SHG + TPF images correlated well with conventional histological examination. This work demonstrated that TPA‐based light treatment provides highly localized intradermal tissue alteration. With further studies on optimizing laser treatment parameters, this two‐photon absorption photothermolysis method could potentially be applied in clinical dermatology. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)</p> </abstract>