TY - JOUR
T1 - Melanin-dependent tissue interactions induced by a 755-nm picosecond-domain laser
T2 - complementary visualization by optical imaging and histology
AU - Jacobsen, Kevin
AU - Ortner, Vinzent Kevin
AU - Fredman, Gabriella Louise
AU - Christensen, Rikke Louise
AU - Dierickx, Christine
AU - Tanghetti, Emil
AU - Paasch, Uwe
AU - Haedersdal, Merete
N1 - © 2023. The Author(s).
PY - 2023/7/14
Y1 - 2023/7/14
N2 - Fractional picosecond-domain lasers (PSL) induce optical breakdown, which correlates histologically to vacuolization in the epidermis and dermis. In this ex vivo porcine study, we sought to establish a framework for the investigation of laser-tissue interactions and their dependence on melanin density. Light- (melanin index: 24.5 [0-100]), medium- (58.7), and dark-pigmented (> 98) porcine skin samples were exposed to a 755-nm fractional PSL and examined with dermoscopy, line-field confocal optical coherence tomography (LC-OCT), conventional OCT, and subsequently biopsied for digitally stained ex vivo confocal microscopy (EVCM) and histology, using hematoxylin and eosin (HE) and Warthin-Starry (WS) melanin staining. Dermoscopy showed focal whitening in medium- and dark-pigmented skin. Similarly, LC-OCT and OCT visualized melanin-dependent differences in PSL-induced tissue alterations. Vacuoles were located superficially in the epidermis in dark-pigmented skin but at or below the dermal-epidermal junction in medium-pigmented skin; in light-pigmented skin, no vacuoles were observed. Histology confirmed the presence of vacuoles surrounded by areas void of WS staining and disrupted stratum corneum in darker skin. The combined use of optical imaging for multiplanar visualization and histological techniques for examination of all skin layers may mitigate the effect of common artifacts and attain a nuanced understanding of melanin-dependent laser-tissue interactions.
AB - Fractional picosecond-domain lasers (PSL) induce optical breakdown, which correlates histologically to vacuolization in the epidermis and dermis. In this ex vivo porcine study, we sought to establish a framework for the investigation of laser-tissue interactions and their dependence on melanin density. Light- (melanin index: 24.5 [0-100]), medium- (58.7), and dark-pigmented (> 98) porcine skin samples were exposed to a 755-nm fractional PSL and examined with dermoscopy, line-field confocal optical coherence tomography (LC-OCT), conventional OCT, and subsequently biopsied for digitally stained ex vivo confocal microscopy (EVCM) and histology, using hematoxylin and eosin (HE) and Warthin-Starry (WS) melanin staining. Dermoscopy showed focal whitening in medium- and dark-pigmented skin. Similarly, LC-OCT and OCT visualized melanin-dependent differences in PSL-induced tissue alterations. Vacuoles were located superficially in the epidermis in dark-pigmented skin but at or below the dermal-epidermal junction in medium-pigmented skin; in light-pigmented skin, no vacuoles were observed. Histology confirmed the presence of vacuoles surrounded by areas void of WS staining and disrupted stratum corneum in darker skin. The combined use of optical imaging for multiplanar visualization and histological techniques for examination of all skin layers may mitigate the effect of common artifacts and attain a nuanced understanding of melanin-dependent laser-tissue interactions.
KW - Animals
KW - Swine
KW - Melanins
KW - Skin/diagnostic imaging
KW - Lasers, Solid-State
KW - Microscopy, Confocal/methods
KW - Tomography, Optical Coherence/methods
KW - Histological Techniques
UR - http://www.scopus.com/inward/record.url?scp=85164759900&partnerID=8YFLogxK
U2 - 10.1007/s10103-023-03811-4
DO - 10.1007/s10103-023-03811-4
M3 - Journal article
C2 - 37450199
SN - 0268-8921
VL - 38
SP - 160
JO - Lasers in Medical Science
JF - Lasers in Medical Science
IS - 1
M1 - 160
ER -