• 대한의용생체공학회:의공학회지
• /
• 제40권6호
• /
• pp.250-259
• /
• 2019

Ophthalmic Laser System is widely used in Selective Laser Trabeculoplasty of Open Angle Glaucoma and Ocular Hypertension. Versatile ophthalmic laser system is a medical device with technology that checks the condition of the treatment area by irradiating a continuous laser pulse on the treatment area, and monitoring the microbubble reaction caused by the temperature increase of the melanosome through the ultrasonic signal and the optical signal sensor. It performs selective laser treatment without damaging the photoreceptor by controlling the wavelength of the laser when microbubbles are detected. This study aims to suggest a guideline for evaluating safety, performance and clinical effectiveness of Versatile Ophthalmic Laser System in accordance with the growing technology. International Standards, Regulations, and Clinical Trial Protocols were investigated and analyzed for this study. As a result of this study, the safety, performance and clinical effectiveness test guideline for Versatile Ophthalmic Laser System were proposed. This guideline will ensure the safety and efficacy of Medical device, and furthermore it is expected to be able to promote the development of technology development by supporting a clinical trial plan.

• Medical Lasers
• /
• 제10권3호
• /
• pp.181-184
• /
• 2021

Scars can cause great psychological stress among patients. Currently, there are numerous topical agents, laser and surgical treatments available for skin rejuvenation and scar minimization. Laser-assisted drug delivery (LADD) is a treatment method that increases drug delivery by stimulating the skin physically and chemically to enhance the penetration of topical agents. This is one of the areas of great interest in the treatment of various skin diseases in addition to its use for cosmetic purposes. In particular, LADD is relatively non-invasive and has advantages in terms of accessibility and stability. Poly-L-lactic acid (PLLA) is a collagen stimulator known to gradually restore skin volume by inducing inflammation and fibroplasia. Herein, we report a case of treatment of an atrophic scar with fractional carbon dioxide laser-assisted PLLA delivery.

• 대한의용생체공학회:의공학회지
• /
• 제40권6호
• /
• pp.230-234
• /
• 2019

Medical laser equipment using optical energy is used to surgery and treat diseases by destroying and removing tissue. Domestic laser equipment has been used steadily in the skin and cosmetics sectors and has been changed to radiate high-power energy in a wide range to shorten patient treatment time. However, side effects such as burns and damage of normal tissues occurred. To solve this problem, techniques for detecting lesions using an imaging device and selectively radiating the laser have been developed. In this study, we proposed an evaluation method to evaluate the safety and performance of target detection accuracy, laser irradiation accuracy and motion protection device technology derived from product analysis and investigation. Finally, the validity of the evaluation method was evaluated by evaluating the imaging device based laser equipment as the proposed evaluation method.

• 대한의생명과학회지
• /
• 제14권3호
• /
• pp.167-172
• /
• 2008

We compared the clinical efficacy of LED therapy using 880 nm and 630 nm LED to test collagen accumulations in subcutaneous tissue of mouse after LED irradiation by measuring the quantity of collagen. 880 nm and 630 nm LED was irradiated on the back of ICR mouse given at $10.8J/cm^2$ followed for 30 minutes everyday for 5 weeks. Histological observation was performed by Hematoxylin & Eosin staining and Masson's Trichrome collagen staining. We also used Sircol soluble collagen assay kit for measuring the amounts of collagen in the mouse skin tissue after 1, 3, and 5 weeks post LED irradiation, respectively. Collagen generation was found at subcutaneous tissue, and the quantity of collagen in 880 nm LED group had grown more than that of 630 nm LED group at 5 weeks follow-up later. About 75% more efficacies for collagen generation were found in the group of 5th week of 880nm LED irradiation. The efficacy of 880nm LED could be more useful than 630 nm LED for synthesizing collagens in mouse subcutaneous tissue as time followed.

• Transactions on Electrical and Electronic Materials
• /
• 제16권2호
• /
• pp.65-69
• /
• 2015

Low level laser therapy (LLLT) has facilitated an improvement in acupuncture treatment. In this study, we stimulated Shaochong (HT9), Dadun (LR1), Shaohai (HT3), and Yingu (KI10) acupoints with pulsed laser diodes 532 nm [green laser] and 658 nm [red laser] in rats with induced middle cerebral artery occlusion(MCAO). The animals were divided into 6 groups: intact control; MCAO control without LLLT; LLLT with red laser at HT9·LR1 and HT3·KI10 (RR); LLLT with green laser at HT9·LR1 and HT3·KI10 (GG); LLLT with green laser at HT9·LR1 and red laser at HT3·KI10 (GR); and LLLT with red laser at HT9·LR1 and green laser at HT3·KI10 (RG). We evaluated the immunohistochemical changes in the hippocampal CA1 region, and complete blood count changes. Compared to the MCAO control group, the RG group showed a significant decrease in Bax and cytochrome c levels in the hippocampus, and a significant increase in hemoglobin level, hematocrit, total white blood cell, neutrophil, lymphocyte, monocyte, and erythrocyte counts.

• 대한의용생체공학회:의공학회지
• /
• 제17권4호
• /
• pp.491-498
• /
• 1996

The development of a compact two-wavelength Nd:YAG laser for dental and ENT applications is presented. The Nd:YAG resonator generates either 1.06$\mu$m or 1.32$\mu$m. The wavelength selection is made at the control panel. The Nd:YAG laser parameters at 1.06$\mu$m are ; the maximum pulse duration of 150$\mu$s, repetition rates of I-100Hz, and the maximum average power of 25W. At 1.32$\mu$m, the pulse duration is the same where the repetition rates and the maximum average power are I-30Hz and lOW respectively. High voltage power supply consists of a simmer module and two identical high voltage DC converters. In order to make a complete medical laser system, an optical fiber delivery unit, foot pedal and water spray handpiece are also developed. The wavelength selection is reliable since no movement of optical or mechanical components is required. The high voltage power supply is compact, easy to be maintained and applicable for other laser systems due to its modular design.

• Medical Lasers
• /
• 제10권1호
• /
• pp.49-51
• /
• 2021

The perioral region, which is one of the most conspicuous parts of the face, plays a significant role in interpersonal communication. However, the perioral region is highly susceptible to scarring and pigmentation and is difficult to treat. The causes of perioral hyperpigmentation are many, including physiologic reasons, systemic diseases, drugs, and infections. In the treatment of perioral hyperpigmentation, the cause of the disease must be diagnosed first. Management includes lifestyle modifications such as reducing the UVA exposure time, use of topical treatments including hydroquinone and retinoids, and physical therapy including laser therapy. We report a case of perioral hyperpigmentation treated with 1,064-nm Q-switched neodymium:yttrium-aluminum-garnet laser toning.

• Medical Lasers
• /
• 제10권4호
• /
• pp.242-245
• /
• 2021

Acne vulgaris is a common inflammatory skin disease of the pilose-baceous unit. It appears as lesions consisting of comedones, papules, pustules, and nodules of varying shapes and severity. In general, the first-line treatment for acne vulgaris includes topical and oral medication. Recently, various physical modalities have also been investigated. The use of laser therapy is steadily increasing because of its fewer side effects, short procedure time, and rapid results. In particular, laser therapy assisted with carbon suspension application is effective for acne vulgaris but may sometimes result in discomfort due to odor and dust formation during the procedure. Herein, we report that acne vulgaris and enlarged facial pores can be safely and effectively treated with laser therapy assisted with diamond particle suspension and gold microparticle application, which can address the discomfort caused by the carbon suspension application.

• 대한의용생체공학회:의공학회지
• /
• 제32권3호
• /
• pp.270-277
• /
• 2011

Laser cartilage reshaping(LCR) is a promising method for reshaping cartilage by using laser irradiation to maintain permanently modifies its shape. However this method has not been fully understood due to the limited scientific researches. The purpose of this study is to analyze optical and thermal characteristics of cartilage during laser irradiation. After analyzing Monte Carlo simulation for the comparison of laser fluence distributions with different laser wavelengths the characterization of the spectral changes during Nd:YAG laser(${\lambda}$ = 1444 nm) irradiation was investigated in the ranges of 900-1700 nm with double integrating spheres. The surface temperature distribution changes during laser irradiation were investigated with an infrared camera. The quantitative measurements of optical and thermal characteristics in cartilage after laser irradiation were correlated with the transition of water flux(from bound to free water) and this study may be useful for better understanding of biophysical transformation phenomena in cartilage after laser heating.

• Clinical and Experimental Reproductive Medicine
• /
• 제26권2호
• /
• pp.185-192
• /
• 1999

The present study was performed to investigate the efficacy and safety of laser assisted hatching (AH) on mouse embryos. Non-contact $1.48{\mu}m$ diode laser system used to create a precise hole on zona pellucida. 2-cell embryos were collected from the mice (ICR) that had the coitus vaginal plug confirmed at 48 hours after hCG injection. Collected 2-cell embryos were cultured in the HTF medium supplemented with 0.4% BSA. For experiments, embryos at 8-cell stage were used after 18-22 hours in culture. After assisted hatching, the embryos were further cultured in HTF medium containing 0.1% PVP (anti-hatching system) for 3 days. For evaluate efficiency of laser on mouse embryo hatching, the effect of AH methods (acidic tyrode, pronase and laser), the number of artificial holes (1, 2 and 3 hole) and the irradiation time of laser (2, 4, 6, 8 and 10 ms) were examined. Hatching rates of laser AH group (95.2%) was significantly higher than that of control group (50.8%), but there was no differences among the laser (95.2%), acidic tyrode (100%) and pronase (98.5%) groups. Hatching rates of the number of zona pellucida opening by laser, there were no differences among the 1 hole (87.5%),2 hole (92.1%) and 3 hole (85.9%) groups. Developmental and hatching rates of embryos according to laser irradiation time were similar in the treatment groups. Therefore, these results suggest that laser AH using non-contact $1.48{\mu}m$ diode laser is a simple and accurate and effective procedure for AH. Based on these results, laser AH could be use safely for human ART program.