• Proceedings of the Microbiological Society of Korea Conference
• /
• 2005.05a
• /
• pp.206.2-206
• /
• 2005

• Biomedical Science Letters
• /
• v.14 no.3
• /
• pp.173-178
• /
• 2008

With the widespread use of laser in medical and industrial settings, the incidence of laser injury to the ocular continues to grow among workers involved in handling lasers. The aim of this study is to compare ocular damages after irradiation with various laser wavelengths and power density. Ocular of pigmented rats was irradiated with $CO_2$ laser, 1064 nm Nd:YAG laser, and 532 nm diode laser. We observed damage of cornea, lens, and retina using slit lamp microscope and funduscopy. H&E staining of histopathology were applied to study the specimens. The higher exposure ($200mW/cm^2$, 10 sec) with $CO_2$ laser resulted in severe damage at the cornea. For the 1064 nm Nd:YAG laser, the higher exposure than $10mW/cm^2$ (10 sec) resulted in damage at the cornea and lens. Further, with the 532 nm diode laser, retinal lesions were induced when $10mW/cm^2$ (0.25 sec) was delivered to the eye. Theses results suggest that the ocular damages are different from various laser wavelength and power density.

• Proceedings of the Korean Society of Life Science Conference
• /
• 2008.10a
• /
• pp.49.2-49.2
• /
• 2008

• Medical Lasers
• /
• v.10 no.2
• /
• pp.68-75
• /
• 2021

Medical lasers have been widely used for various diseases. Despite the notable benefits, lasers could cause several complications such as skin burn, eye injury, airway fire, and so on. These accidents may occur not only with patients, users of the laser, or laser handlers but also to people passing in front of the laser treatment room. Although there is a risk associated with the laser, most of them can be prevented through good training, use of proper protection equipment, and ensuring the safe operation of the laser at all times. Due to the increasing use of lasers and the growing interest in their use, medical institutions should particularly emphasize the safe use of lasers and introduce systems for laser safety.

• Clinical Endoscopy
• /
• v.55 no.3
• /
• pp.434-442
• /
• 2022

Background/Aims: Covered self-expandable metallic stents (CMSs) are widely used for malignant distal biliary obstructions (MDBOs) caused by pancreatic carcinoma. This study compared the efficacy and safety of the laser-cut-type and braided-type CMSs. Methods: To palliate MDBOs caused by pancreatic carcinoma, the laser-cut-type CMSs was used from April 2014 to March 2017, and the braided-type CMSs was used from April 2017 to March 2019. The tested self-expandable metallic stents were equipped with different anti-migration systems. Results: In total, 47 patients received CMSs for MDBOs (24 laser-cut type, 23 braided-type). The time to recurrent biliary obstruction (TRBO) was significantly longer in the braided-type CMSs (p=0.0008), and the median time to stent dysfunction or patient death was 141 and 265 days in the laser-cut-type CMSs and braided-type CMSs, respectively (p=0.0023). Stent migration was the major cause of stent dysfunction in both groups, which occurred in 37.5% of the laser-cut-type CMSs and 13.0% of the braided-type CMSs. There were no differences in the survival duration between the groups. Conclusions: The TRBO was significantly longer for the braided-type CMSs with an anti-migration system than for the laser-cut-type. Stent migration tended to be less frequent with the braided-type CMSs than with the laser-cut-type CMSs.

• Laser Solutions
• /
• v.17 no.4
• /
• pp.1-6
• /
• 2014

Femtosecond laser induced shock generation in water and vitreous humor of enucleated porcine eyeball was investigated. When focusing the femtosecond laser into the liquid mediums, the acoustic waves with a frequency of about 15.6kHz could be observed by using wide-band microphone. The amplitude of the acoustic signals from water has attained a maximum under a laser power of about 5mW. Further increment of the power results in a decrement of the acoustic signals due to nonlinear optical process including filamentation of laser beam. We have further investigated the effect of femtosecond laser induced acoustic waves by applying the laser pulse into enucleated porcine eyeball. The comparative studies on both healthy and diseased eyeballs led us propose that the femtosecond laser pulses could be utilized as a novel tools for treatment of partially detached retina layers from their choroid structures.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.19 no.2
• /
• pp.192-201
• /
• 2006

Objectives : Recently, He-Ne laser has been used for clinical purpose. We study the medical basis of He-Ne laser therapy and We make a proposal concerning the clinical application of using He-Ne laser in Medicine. Methods : We have selected data related to He-Ne laser therapy and study how to use He-Ne laser in clinic. Results : In biology, He-Ne laser therapy has been effects of an improve in skin regeneration an improve in peripheral and central nerve regeneration an improve in muscle regeneration, an anti-inflammation an alleviation of pain and a bone repair. In oriental medicine, He-Ne laser has been used to laser acupuncture and laser oriental physical treatment. In clinic, He-Ne laser have been used to care several parts like as facial palsy, facial spasm, trigeminal neuropathy, rhinitis and tinnitus. Recently, there is argument that He-Ne laser therapy is suitable to medical insurance. Conclusions : Laser therapy in oriental medicine is widespread and We can apply He-Ne laser to facial palsy, facial spasm, trigeminal neuropathy, rhinitis, tinnitus by using laser acupuncture or laser oriental physical treatment. Till now the whole mechanisms are not fully understood, so we hope to study these mechanisms actively and make suitable to medical insurance device in the near future.

• Biomedical Science Letters
• /
• v.15 no.1
• /
• pp.81-86
• /
• 2009

Lasers are necessity in our life related to the fields of medicine and cosmetic surgery. With 808 nm diode laser and $CO_2$ laser, we made some wounds on a dorsum of rat by laser irradiation. All of irradiations shows thermal effects on the whole region of skin tissues. They make wound damage depending on laser power and irradiation time. Because a collagen is plays an important role in tissue repair, we studied collagen accumulation in wound tissue. For wound healing, collagen accumulation was found in the near region of damage in epidermis and dermis layer of the rat skin. In case of the quantitative analysis of collagen in wound tissue, the amount of collagen in wound tissue by $CO_2$ laser irradiation is higher than that of 808 nm diode laser irradiation. And re-epithelialization was significantly faster in wound by $CO_2$ laser irradiation compared with that of 808 nm diode laser irradiation.

• Archives of Plastic Surgery
• /
• v.32 no.2
• /
• pp.149-154
• /
• 2005

Low-power laser(LPL) delivers a small amount of energy without elevation of tissue temperature. LPL has been reported to have biostimulation effects including anti-inflammatory, analgesic, regenerative, immunocorrective, and vasodilative effects. However, the effect of LPL on hair growth has rarely been studied. We investigated the effect of LPL on hair growth in the mouse. After depilation of back skin of mice, we classified the mice into 4 groups: control, laser irradiated group, $MoandMore^{(R)}$ applied group, and Spella $707^{(R)}$ applied group. Laser irradiation or application of these drugs were performed on the back skin of the mice for 30 days. The results are summarized as follows. Hair growth of control was first observed at 13 days after depilation, and complete hair regrowth was observed at 25 days. Hair growth of both laser irradiation group and $MoandMore^{(R)}$ applied group was first observed at 9 days after depilation, and complete hair regrowth was observed at 20 days. Hair growth of Spella $707^{(R)}$ applied group was firstly observed at the 9 days after depilation, and complete hair regrowth was observed at the 15 days. Hair growth started at the irradiation site in the laser irradiation group, but it started at the random sites in other groups. In conclusion LPL irradiation have a stimulating effect on the hair growth in the mouse.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.27 no.3
• /
• pp.205-212
• /
• 2014

Purpose: This study aims to prove effects of an oriental medical complex therapy on vitiligo patients who have experienced the Eximer laser therapy. Method: The study conducted its investigation targeting these four patients who have not been observed with any satisfactory reaction to the Eximer laser therapy. The study analyzed the findings through the comparison on the pictures before and after the therapy. Result: After comparing the pictures, the study confirmed positive changes in the conditions of the patients. The oriental medical complex therapy turned out to be effective enough to treat the patients who have gone through the Eximer laser therapy before. Conclusion: Such result leads the study to a conclusion that the oriental medical complex therapy can be an effective way to treat these patients who do not have a satisfactory reaction to the Eximer laser therapy. In addition, the author of the study suggests that more clinical trials should be conducted.