title: Feasibility of ablative fractional laser-assisted drug delivery with optical coherence tomography.
abstract: Fractional resurfacing creates hundreds of microscopic wounds in the skin without injuring surrounding tissue. This technique allows rapid wound healing owing to small injury regions, and has been proven as an effective method for repairing photodamaged skin. Recently, ablative fractional laser (AFL) treatment has been demonstrated to facilitate topical drug delivery into skin. However, induced fractional photothermolysis depends on several parameters, such as incident angle, exposure energy, and spot size of the fractional laser. In this study, we used fractional CO2 laser to induce microscopic ablation array on the nail for facilitating drug delivery through the nail. To ensure proper energy delivery without damaging tissue structures beneath the nail plate, optical coherence tomography (OCT) was implemented for quantitative evaluation of induced microscopic ablation zone (MAZ). Moreover, to further study the feasibility of drug delivery, normal saline was dripped on the exposure area of fingernail and the speckle variance in OCT signal was used to observe water diffusion through the ablative channels into the nail plate. In conclusion, this study establishes OCT as an effective tool for the investigation of fractional photothermolysis and water/drug delivery through microscopic ablation channels after nail fractional laser treatment.
authors.affiliation: Department of Dermatology, Chang Gung Memorial Hospital, 5 Fusing St., Kwei-Shan, Tao- Yuan, 33302, Taiwan ; College of Medicine, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan.
authors.forename: Chih-Hsun
authors.initials: CH
authors.lastname: Yang
authors.affiliation: Department of Electrical Engineering, School of Electrical and Computer Engineering, College of Engineering, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan ; Graduate Institute of Electro-Optical Engineering, School of Electrical and Computer Engineering, College of Engineering, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan ; mttsai@mail.cgu.edu.tw.
authors.forename: Meng-Tsan
authors.initials: MT
authors.lastname: Tsai
authors.affiliation: College of Medicine, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan ; Department of Ophthalmology, Chang Gung Memorial Hospital, 5 Fusing St. Kwei-Shan, Tao- Yuan, 33302 Taiwan.
authors.forename: Su-Chin
authors.initials: SC
authors.lastname: Shen
authors.affiliation: Department of Dermatology, Chang Gung Memorial Hospital, 5 Fusing St., Kwei-Shan, Tao- Yuan, 33302, Taiwan ; College of Medicine, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan.
authors.forename: Chau Yee
authors.initials: CY
authors.lastname: Ng
authors.affiliation: College of Medicine, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, 33302 Taiwan ; Department of Pathology, Chang Gung Memorial Hospital, 5 Fusing St., Kwei-Shan, Tao- Yuan, 33302 Taiwan.
authors.forename: Shih-Ming
authors.initials: SM
authors.lastname: Jung
keywords: (110.4500) Optical coherence tomography; (170.1870) Dermatology; (170.2655) Functional monitoring and imaging; (290.1350) Backscattering