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Comparison of fractional neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond laser and fractional 1550-nm erbium fiber laser in facial acne scar treatment
摘要： To compare the safety and efficacy of fractional neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond laser and fractional 1550-nm erbium fiber laser in acne scar treatment and to assess the adverse effects and complications of the two devices. Thirty patients with cosmetically similar acne scars on both sides of the faces were enrolled and treated four times at 4-week intervals. Each side of the face was treated with either fractional 1064-nm Nd:YAG picosecond laser or fractional 1550-nm erbium fiber laser. Efficacy was evaluated using digital photography taken at baseline and 5 months by a blinded dermatologist using the ECCA grading scale (échelle d’évaluation clinique des cicatrices d’acné). Patient overall satisfaction and self-rated improvement scores were recorded at baseline and 5 months. Adverse effects were recorded at every visit. Twenty-seven patients completed the study. Both devices demonstrated significant median ECCA score improvement from baseline (P < 0.001). However, there was no significant difference between the two in terms of median ECCA score improvement, patients’ perception of scar improvement, and overall satisfaction. Considering the adverse effects, more pinpoint bleeding was significantly observed with the picosecond laser (P = 0.002), whereas more pain was noted with the erbium laser (P < 0.001). Both fractional 1064-nm Nd:YAG picosecond laser and fractional 1550-nm erbium fiber laser are safe and effective in the treatment of acne scars. Costs should be taken into consideration when deciding on which device to use to maximize treatment outcomes.
关键词： Erbium fiber laser,Acne scar,Picosecond laser,Acne scar treatment,Fractional laser
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Tunable Near 3-μm Difference Frequency Generation using Ytterbium and Broadband Seed Erbium Fiber Lasers
摘要： The absorption peaks corresponding to vibrational energy levels of various molecules are located in the mid-infrared (mid-IR) spectral range. For instance, the interatomic bonding of hydrogen and another heavier element (e.g. C-H, O-H, N-H) that is a part of some organic and inorganic molecules is characterized by the absorption peak located near 3μm wavelength. Laser sources operating at this wavelength can be useful tools for medical applications, non-metallic materials processing, and spectroscopy [1]. The study of the interaction of various organic substances with mid-IR radiation is rather challenging because of their great diversity and chemical composition complexity. An application of the laser source with high output power and tunable wavelength can significantly facilitate possible investigation problems [2,3]. This research is devoted to the elaboration of the tunable laser source of mid-IR radiation using single pass difference frequency generation of the pump (1.03 μm) and seed (1.55 μm) radiation in periodically poled lithium niobate (PPLN) crystal (see Fig.1 (a)). Pulsed ytterbium and erbium fiber lasers were used as the pump and seed radiation sources respectively. Both of them were assembled basing on a MOPA optical scheme, pulse duration was about 2 ns and repetition rate was 3 MHz. The average output power of Yb-laser was up to 50 W, which is five times higher than the maximum power of Er laser source. The wavelength corresponding to the difference frequency generation for these fiber lasers lies in the 3 μm region. The spectrum of the seed radiation was considerably broadened in the delivery fiber due to the four-wave mixing and Raman scattering. So that, it was possible to obtain the seed radiation in the spectral range from 1.55 m to 1.60 μm. The selective parametric amplification region of seed radiation can be shifted by changing PPLN temperature, as a result, the idler radiation wavelength tuning was achieved. We obtained the idler tuning in 2.9–3.1 μm wavelength range by changing the PPLN temperature from 45 °C to 110 °C. This tuning range was restricted by the spectral width of the Er-laser radiation. The idler radiation power varied from 5.5 W to 8.0 W in the whole tuning range (see Fig.1 (b)). The conversion efficiency reached 15% in respect to the Yb-laser power. As we were not able to measure directly the mid-IR radiation spectrum but it was derived using the experimentally measured spectrum of the amplified seed radiation. Normalized calculation results are shown in Fig.1 (c). The spectral width of the output mid-IR radiation reached 20-30 nm (at a 3 dB FWHM level).
关键词： tunable laser source,mid-infrared,difference frequency generation,PPLN crystal,erbium fiber laser,ytterbium fiber laser
更新于2025-09-11 14:15:04