title: Photodamage in deep tissue two-photon optical biopsy of human skin.
abstract: Photodamage, induced by femtosecond laser radiation, was studied in thick samples of human skin tissue (healthy skin and neoplastic lesions). Photobleaching, photoionization, and thermomechanical damage effects were characterized comparatively. The laser power dependence of the damage rates allowed to connect macroscopic effects to underlying molecular processes. Optical effects were correlated to histopathological changes. Tissue alterations were found only from thermomechanical cavitation and limited to superficial layers of the epidermis. From the depth-dependencies of all damage thresholds a depth-dependent power-compensation scheme was defined allowing for damage-free deep tissue optical biopsy. Damage-induced luminescence pattern for different excitation powers and a corresponding threshold analysis.
authors.affiliation: BIOtech Center and Department of Industrial Engineering, University of Trento, via delle Regole 101, 38123, Mattarello, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Dalbosco
authors.affiliation: Department of Physics, University of Trento, via Sommarive 14, 38123, Povo, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Zanini
authors.affiliation: Department of Physics, University of Trento, via Sommarive 14, 38123, Povo, Italy.
authors.forename: Elvira
authors.initials: E
authors.lastname: D'Amato
authors.affiliation: BIOtech Center and Department of Industrial Engineering, University of Trento, via delle Regole 101, 38123, Mattarello, Italy.|Healthcare Research and Innovation Program (IRCS), Bruno Kessler Foundation, via Sommarive 18, 38123, Trento, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Tessarolo
authors.affiliation: Department of Pathology, APSS, S. Chiara Hospital, Largo Medaglie d'Oro 9, 38122, Trento, Italy.
authors.forename: Sebastiana
authors.initials: S
authors.lastname: Boi
authors.affiliation: Department of Dermatology, APSS, S. Chiara Hospital, Largo Medaglie d'Oro 9, 38122, Trento, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Bauer
authors.affiliation: Department of Physics, University of Trento, via Sommarive 14, 38123, Povo, Italy. albrecht.haase@unitn.it.
authors.forename: Albrecht
authors.initials: A
authors.lastname: Haase
authors.affiliation: Department of Physics, University of Trento, via Sommarive 14, 38123, Povo, Italy.
authors.forename: Renzo
authors.initials: R
authors.lastname: Antolini
mesh_terms: D001696:Biomechanical Phenomena / Q000528:radiation effects; D001706:Biopsy / Q000009:adverse effects; D006801:Humans; D057054:Molecular Imaging; D055620:Optical Phenomena; D038761:Photobleaching; D017785:Photons / Q000009:adverse effects*; D012867:Skin / Q000378:metabolism / Q000473:pathology* / Q000528:radiation effects*; D013696:Temperature
keywords: biomedical imaging; multiphoton processes; nonlinear microscopy; photodamage; skin imaging