• Title/Summary/Keyword: medical laser

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Sequential Delivery of Neodymium:Yttrium-Aluminum-Garnet and Alexandrite Laser Pulses for Treating Light Brown Seborrheic Keratoses

  • Cho, Sung Bin;Oh, Doojin;Yoo, Kwang Ho
    • Medical Lasers
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    • v.8 no.1
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    • pp.24-27
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    • 2019
  • Seborrheic keratoses (SKs) have been treated with non-ablative longpulsed (LP) lasers, including LP 532-nm neodymium (Nd): yttrium aluminum garnet (YAG), LP 695-nm ruby, LP 755-nm alexandrite (Alex), and LP 1,064-nm Nd:YAG lasers, with a pulse durations of 1-300 msec. Dual-wavelength LP 755-nm Alex/1,064-nm Nd:YAG laser systems have been used to remove hair follicles and treat various vascular and pigmented disorders by sequentially delivering two pulses of different wavelengths with interpulse intervals in the millisecond range. This paper reports the case of a female patient with multiple, discrete, light brown SKs on the dorsum of both hands that were treated effectively with one session of dual-wavelength LP 1,064-nm Nd:YAG/755-nm Alex laser treatment. The treatment settings for the LP Nd:YAG laser were comprised of a wavelength of 1,064 nm, fluence of 50 J/cm2, pulse duration of 5 msec, and beam size of 3 mm. The settings for the LP Alex laser were comprised of a wavelength of 755 nm, fluence of 50 J/cm2, pulse duration of 5 msec, and beam size of 3 mm. A hybrid mode was used to automatically deliver LP Nd:YAG and LP Alex laser pulses in succession at interpulse intervals of 20 msec. Six weeks after treatment, the patient exhibited remarkable improvement of the light brown seborrheic keratoses and was satisfied with the results.

Ablation Rate and Intrapulpal Temperature by Addition of Water Spray During Er:YAG Laser Irradiation (Er:YAG laser를 이용한 치아삭제시 물분사량이 삭제율과 치수내 온도변화에 미치는 영향)

  • Kim, Jung-Moon;Kim, Mee-Eun;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
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    • v.30 no.3
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    • pp.375-381
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    • 2005
  • Er:YAG laser has been considered a promising alternative to dental drill and many researches indicate that adjustment to variable parameters, including water flow rate, pulse energy and pulse repetition rate, can be made to improve ablation ability and efficiency of the laser. Of these parameters, addition of water spray during irradiation has been thought to ablate dental hard tissue more rapidly and safely. The purpose of this study was to investigate tooth ablation amount by Er:YAG laser irradiation as related to varied water flow rates added and, ultimately to find the most effective water flow rate for ablation. In addition, the temperature change of pulp chamber during irradiation was also monitored on the irradiated and opposite pulpal walls, respectively. An Er:YAG laser with contact mode was employed. Extracted human molars were split into two pieces for ablation experiment. Pulse energies of 200 and 300 mJ with a pulse repetition rate of 20 Hz and 5 water flow rates (1.6, 3.0, 5.0, 7.0, and 10.0 ml/min) were applied. Each irradiation was performed for 3 seconds. According to these parameters, experimental groups were divided into 10 subgroups which consisted of 5 specimens. For temperature experiment, another 5 tooth-specimens were prepared in the manner that pulp chamber was open through access cavity preparation and two temperature-measuring probes were placed respectively on the irradiated and the opposite walls of pulp chamber. From the experiment on ablation amount related to different water flow rates, it was shown that the least water flow rate of 1.6 ml/min ablated more than any other water flow rates (p<0.000). When the irradiation for 3 seconds, combined with the pulse repetition time of 20Hz and the water flow rate of 1.6 ml/min was done to tooth specimen, the temperature rise was not noticeable both on the irradiated and the opposite pulpal walls (less than 3$^{\circ}C$) and there was no significant difference in temperature rise between the two pulse energies, 200 and 300 mJ. From the results of this study, it is suggested that tooth ablation with Er:YAG laser can be done effectively and safely at a energy between 200 and 300 mJ/pulse and a pulse repetition rate of 20 Hz when the lasing is conjugated with the water flow rate of 1.6ml/min.

Intrapulpal Temperature Change during Cavity Preparation on the Enamel and Dentin with an Er:YAG Laser (Er:YAG 레이저를 이용한 법랑질 및 상아질 와동 형성시의 치수내 온도변화)

  • Yang, Hee-Young;Kim, Mee-Eun;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
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    • v.30 no.4
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    • pp.457-464
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    • 2005
  • The purpose of our study was to investigate whether the intrapulpal temperature during cavity preparation of enamel or dentin with Er:YAG laser still remained in range of safety for dental pulp protection when combined with appropriate water flow rate. The effect of different pulse repetition rates at the same pulse energy during ablation was evaluated as well. Caries-free, restoration-free extracted human molar teeth were prepared for the specimen and divided two experimental groups of enamel and dentin. Each group comprised 5 specimens and each of tooth specimens were embedded into a resin block each and measuring probe was placed on the irradiated pulpal walls. For experiments of dentin ablation, enamel layers were prepared to produce dentin specimen with a same dentin thickness of 2 mm. A pulse energy of Er:YAG laser was set to 300 mJ and three different pulse repetition rates of 20 Hz, 15 Hz and 10 Hz were employed. Laser beam was delivered with 3 seconds and less per application over enamel and dentin surfaces constant sized by $3\;mm{\times}2\;mm$ and water spray added during irradiation was a rate of 1.6 ml/min. Temperature change induced by Er:YAG laser irradiation was monitored and recorded While enamel was ablated, there was no significant difference of temperature related to pulse repetition rates(p=0.358) and temperature change at any pulse repetition rate was negligible. Significant statistical difference in temperature changes during cavity preparation in dentin existed among three different pulse groups(p=0.001). While temperature rise was noticeable when the dentinal wall was perforated, actual change of temperature due to Er:YAG laser irradiation was not enough to compromise safety of dental pulp when irradiation was conjugated with appropriate water spray. Conclusively, it can be said that cavity preparation on enamel or dentin with an Er:YAG laser is performed safely without pulp damage if appropriate volume of water is sprayed properly over the irradiated site.

Review of Hair Removal in Traditional Medicine and Its Clinical Application (한의학 임상에서의 제모시술 치료 원리와 활용에 대한 고찰)

  • Jang, In-Soo;Yang, Chang-Sop;Kang, Sei-Young;Sun, Seung-Ho;Lee, Seung-Ho;Choi, Hyug-Yong;Seo, Hyung-Sik
    • Korean Journal of Acupuncture
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    • v.29 no.1
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    • pp.17-22
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    • 2012
  • Objectives : The purpose of this study is to discuss the diagnostic classification of the traditional medicine for pilosis, and the hair removal treatments in traditional medicine and its clinical application. Backgrounds : In recent years, appearance and beauty have become main interest that have positioned in the medical area. In clinical Korean medicine, a variety of methods such as moxibustion, superficial bleeding, multiple microneedling, facial meridian massage, herbal medicine facial pack, laser acupuncture, and intense pulsed light (IPL) have been applied. Methods and Results : Pilosis, a condition of abnormal hair growth, is stated for the first time in the publication, [Pathogenesis and Manifestations of All Diseases] by Chao Yuan-fang in 610 A.D. It shows that pilosis has been recognised as a disease for ages in Asia. Reviewing several publications, we found multiple approaches to pilosis were already existed in korean medicine. They include internal medicinal classification and its' medications. Acupuncture treatments also focused on regulation of radical causes and superficial removal of abnormal hairs. Specific treatments includes body and ear acupuncture, ear acupressure, hypodermic acupuncture, hypodermic acupuncture injection, laser acupuncture treatment. Physical and chemical methods of hair removal were widely invented. we resulted that significant scientific approaches to pilosis are under way in the korean medical field, and found a variety of medical treatments such as herbal medicines and dermatological methods. Conclusions : Hair removal treatments for pilosis in traditional medicine has a long history. Combined with advanced modern technology it can achieve greater advance in cosmetology.

Cell Death Inhibition Effect of Antioxidant Activity by 630 and 850 nm LEDs in RAW264.7 Cells

  • Hee Eun Kim;Eun Young Kim;Jin Chul Ahn;Sang Joon Mo
    • Current Optics and Photonics
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    • v.8 no.5
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    • pp.441-455
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    • 2024
  • This study objective was to evaluate the effects and mechanisms of low-level laser therapy in H2O2-induced cell death in mouse macrophage RAW264.7 cell. After irradiation with 630 and 850 nm wavelength diode lasers with an intensity of 10 mW/cm2 in RAW264.7 cells treated with 0.7 Mm H2O2, the effects and mechanisms of the two wavelengths on cell death inhibition were evaluated using MTT assay, ROS staining, TUNEL assay, flow cytometry analysis, and Western blot analysis. As a result, 630 or 850 nm light-emitting diodes (LED) were irradiated for 10 or 40 minutes to increase cell viability with H2O2 by about 1.7- or 1.6-fold, respectively. In addition, irradiation with two LEDs showed significant ROS scavenging effects, and TUNEL-positive cells were significantly reduced by 45.7% (630 nm) and 37.8% (850 nm) compared to cells treated with H2O2 alone. The Bax/Bcl-2 ratio of cells irradiated with both LEDs was significantly lower than that of cells treated with H2O2 only, and the expression of procaspase-3 and cleaved PARP was also significantly expressed in the direction of suppressing cell death. In conclusion, ROS scavenging activity by both LEDs irradiation leads to the expression of cell death pathway proteins in the direction of inhibiting cell death.

A Mechanical Model of Excimer Laser Surgery (엑시머 레이저 수술의 역학적 모델)

  • Shin, Jung-Woog;Kim, Jong-Hyun
    • Proceedings of the KOSOMBE Conference
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    • v.1993 no.05
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    • pp.57-60
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    • 1993
  • A finite element-based computer simulation of excimer laser susery was conducted to study some factors on the surgery. In particular, the radius of curvature at the apex of the cornea was examined under various surgical conditions. Corneal tissue was assumed to be a nearly incompressible, linear elastic, homogeneous, isotropic material under very small deformation. The geometry of the human cornea was taken from the experimental data[1]. The simulation utilized ANSYS(Swanson Analysis System Inc.Rev.4.4A). In this study, the major factors which affect the outcomes of the excimer laser surgery were investigated. First, two patterns of surgery with various surgery thickness(40-70micrometers) were examind. The pattern#1 describes the meridian from the apex to the edge of the surgery area to be straight. And the corresponding meridian of the pattern 2 can be expressed as a quardratic function. The results show that the pattern #2 is more realistic and effective. Then, the effects of other factors were investigated based on the pattern #2. Other factors are:various diameters of the surgical area (3-8 milimeters), Young's modules(3.5-4.5MPa), and depth of surgery at the apex(40-70micrometers). Compared with the computer simulation of the radial keratotomy surgery[2], the excimer laser surgery was proven to be more effective in treating myopia patients. In conculusion, the results of the simulation are qualitative agreement with clinical experience[3] indicating the potential of the finite element model of the surgery as a guideline to the surgeon before actual surgery.

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Effectiveness of the Pico-toning Technique for the Treatment of Melasma with a Low Fluence 1,064-nm Nd:YAG Laser in Asian Patients

  • Kim, Dong Gyu;Nam, Seung Min;Shin, Jin Soo;Park, Eun Soo
    • Medical Lasers
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    • v.9 no.2
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    • pp.166-171
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    • 2020
  • Background and Objectives Melasma is an acquired pigmentary disorder characterized by brown or dark brown colored macules and patches which mostly involve the face. Compared to nanosecond lasers, picosecond lasers have fewer adverse effects on surrounding tissues and give better results for melanin fragmentation. The purpose of this study was to evaluate the efficacy of the pico-toning technique using a low fluence 1,064-nm Nd:YAG laser on melasma patients. Materials and Methods This study is a retrospective analysis of melasma cases treated using the pico-toning technique from June 2017 to November 2020. Based on photographic images, the modified Melasma Area and Severity Index (mMASI) score was blind evaluated by two independent plastic surgeons. Patient satisfaction was assessed through a 5-point Likert scale questionnaire after treatment sessions. All adverse effects and complications were reviewed based on medical records. Results A total of 23 patients were included in the study. The mMASI scores for baseline and 2 months after the last procedure were 5.1 ± 1.4 and 2.6 ± 0.4, respectively. The mean mMASI score reduced significantly after the treatment session (p < 0.05). The patient satisfaction score with the procedure was 3.8 ± 1.0. The subject satisfaction score and difference in the mMASI score before the procedure and 2 months after the last procedure showed a significant correlation. Adverse effects observed in this study were erythema (n = 1) and edema (n = 1). Conclusion The results of the study show that the pico-toning technique is effective in Asian patients with melasma. We believe that safety was enhanced by using low fluence, and thus better results were achieved with fewer adverse effects.

Korean Pharmacopuncture Meets Austrian High-Tech Acupuncture - A Short Review Article Including a Bibliometric Analysis of Pharmacopuncture over the Last 15 Years - Pharmacopuncture and Europe

  • Litscher, Daniela;Litscher, Gerhard;Kang, Dae-In
    • Journal of Pharmacopuncture
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    • v.16 no.1
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    • pp.7-11
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    • 2013
  • Objective: Pharmacopuncture, a new therapy in traditional medicine, has attracted significant attention since its introduction to the Western world. This short review article employs a database analysis to examine the profile of publication activity related to pharmacopuncture. Methods: Three databases were searched: PubMed, Embase, and Cochrane. About 300 papers related to the topic "pharmacopuncture" were found in these three most-commonly-used databases. Results: Fourteen papers are described in detail and are discussed in the context of the research performed at the Medical University of Graz, especially by the Frank Bahr Research Group "Auriculomedicine and Pharmacopuncture." Conclusion: High-tech research methods concerning future pharmacopuncture studies are briefly discussed.

Development of a Transcutaneous Optical Information Transmission System for Total Artificial Heart Using Near Infrared Laser

  • Lee, Jung-Hoon;Kim, Wook-Eun;Choi, Jong-Hoon;Ahn, Jae-Mok;Min, Byoung-Goo
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.05
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    • pp.64-67
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    • 1997
  • In the total artificial heart(TAH), a transcutaneous information transmission system(TITS) is vely important to monitor the TAH status and detect the device failure, and repair the possible problems. First of all, the communication channel(skin) and method were simulated in terms of transmittance, scattering, reflection and absorption, then the system was designed with size reduction including low power consumption and reliability compared to the previous one. The informations are transmitted through the skin(approximately 1cm in depth) by frequency modulated near infrared(NIR) pulses using 780nm laser diodes as transmitters and photodiode as receiver with high speed and high spectral sensitivity. The logic high and low frequencies are 3MHz, 1MHz respectively. The system is a bidirectional data link for more than 38.4Kbps data rate, full-duplex with a bit error rate of less than $10^{-5}$.

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