Safe Use of Medical Lasers

우승훈,Phil-Sang Chung,이상준 대한의학레이저학회 2021 MEDICAL LASERS Vol.10 No.2

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.

Favorable Vocal Fold Wound Healing Induced by Platelet-Rich Plasma Injection

우승훈,정한신,김진평,고은하,이선욱,진성민,김동훈,손진희,이상혁 대한이비인후과학회 2014 Clinical and Experimental Otorhinolaryngology Vol.7 No.1

Objectives. To introduce a new injection material for vocal fold diseases, which could be readily translated to clinical prac- tice, we investigated the effectiveness of platelet-rich plasma (PRP) injection on the injured vocal fold in terms of his- tological recovery. Methods. Blood samples were drawn from New Zealand White rabbits and PRP was isolated through centrifugation and separation of the samples. Using a CO 2 laser, we made a linear wound in the 24 vocal fold sides of 12 rabbits and in- jected each wound with PRP on one vocal fold side and normal saline (NS) on the other. Morphologic analyses were conducted at 2, 4, and 12 weeks after injection, and inflammatory response, collagen deposit, and changes in growth factors were assessed using H&E and masson trichrome (MT) staining and western blot assay. Results. PRP was prepared in approximately 40 minutes. The mean platelet concentration was 1,315,000 platelets/mm 3 . In morphological analyses, decreased granulation was observed in the PRP-injected vocal folds (P<0.05). However, the irregular surface and atrophic change were not difference. Histological findings revealed significant inflammation and collagen deposition in NS-injected vocal folds, whereas the PRP-injected vocal folds exhibited less (P<0.05). Howev- er, the inflammatory reaction and fibrosis were not difference. In western blot assay, increased amounts of growth factors were observed in PRP-injected vocal folds. Conclusion. Injection of injured rabbit vocal folds with PRP led to improved wound healing and fewer signs of scarring as demonstrated by decreased inflammation and collagen deposition. The increased vocal fold regeneration may be due to the growth factors associated with PRP.

후두의 말초 운동신경 지배

우승훈,김진평,Woo, Seung-Hoon,Kim, Jin-Pyeong 대한후두음성언어의학회 2009 대한후두음성언어의학회지 Vol.20 No.2

The laryngeal peripheral nerve system is presented on the basis of our results in the animal. This present paper forcused on the localization of each laryngeal motoneuron, the myotopical arrangements of motoneurons innervating the pharyngeal and esophageal striated muscles whitin the nucleus ambiguous in the motor nerve supply, and the pathway to the larynx in the sensory and symphathetic nerve supplies. Regarding the parasympathetic nerve supply, the neural ganglia and the ganglionic cells in and around the laryngeal nerves and in the laryngeal framework are demonstrated. Most of this innervations, however, is still unclear. In addition, we presented about external branch of superior laryngeal nerve and inferior laryngeal nerve. Discuss from the literature are also reported.

자간증 환자의 마취 유도 중 발생한 뇌실질내 출혈 및 뇌 경색에 의한 사망 1례 : A Case Report

우승훈,김정원,홍기혁 인제대학교 1994 仁濟醫學 Vol.15 No.1

현대 마취의들이 전자간증과 자간증의 마취 유도 및 유지에 있어 혈압 상승을 유발할 수 있는 약물들을 피함으로써 그에 의한 뇌실질 내 출혈 및 뇌경색에 의한 사망례는 드물어졌다. 본 교실에서는 태아곤란으로 응급 제왕절개술을 시행하기 위해 마취유도를 하던 중 뇌실질 내 출혈과 뇌경색으로 인해 사망한 자간증 환자를 경험하였기에 문헌적 고찰과 함께 보고한다. While the mordern anesthesiolosists prefer the drugs that may not elevate the blood pressure in preeclampsia and eclampsia, during induction and maintenance of anesthesia, the fatal case resulted of ICH and cerebral infarction rarely occur. We experienced a case of ICH and cerebral infarction due to eclampsia during inductuon of anesthesia for emergency Cesarian section. She was net awakened after cessation of the operation, and died of multiple organ failures from the complication of eclampsia.

ACTIVE DIFFERENTIAL CONTROL FOR IMPROVED HANDLING PERFORMANCE OF FRONT-WHEEL-DRIVE HIGH-PERFORMANCE VEHICLES

우승훈,차현수,이경수,장성윤 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.2

This paper presents an active differential control system to improve handling and acceleration performance. Conventional front-wheel-drive cars have certain disadvantages including a lack of acceleration and excessive understeer during acceleration in turn. To address this problem, we propose understeer prevention logic. First, for a rapid response, the driving torque is distributed in advance to the inner and outer wheels according to the magnitude of the estimated traction potential in the wheels. If wheel spin occurs, then additional driving torque is transmitted to the outer wheel in proportion to the increment of the inner wheel speed versus the outer wheel. However, the torque transfer to the outer wheel is limited in proportion to the excess speed of the outer wheel compared with the non-driving wheel to prevent power slides. Oversteer prevention logic can improve yaw damping. The algorithm transmits driving torque from the outer wheel to the inner wheel in proportion to the yaw rate that exceeds the target. This algorithm was then evaluated via vehicle tests. The electronic limited slip differential with the proposed algorithm was applied to mass production, and it received positive feedback from international media.

슬관절통 환자에서 Hyaluronic acid의 치료효과에 대한 추적 조사

우승훈,이우용 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.4

Objectives : Hyaluronic acid is a component of synovium and is secreted into the joint space. Its role is anti-inflammatory and protects cartilage from injury and maintain viscosity in the joint space. It has been known effective and to have few complication for the treatment of the degenerative arthritic patients compared to adrenocort cotropic hormone. Until now there has been few study for long term effect of hayaluronic acid, This study was designed for the evaluation of long term effect of hyaluonic acid. Methods and Materials : We evaluated 36 degenerative arthritic patients who were graded 1 or 2 by Kellgren-Laurence classification. 5 injections of hyaluronic acid into the knee were done weekly for 5 weeks for the patients. We evaluated their visual analogue scale(VAS) score weekly during first month after then monthly until 6 month after infection and compared with pretreatment score. Lastly we asked them how to be satisfactory after 6 months. Results : Before injection, median value of VAS score was 9.40 and 6 months after injections, it was 7.00. The result of satisfaction questionnaire was as follows. Very satisfactory patients were none, satisfactory ones 3, 'so so' patient 16, not satisfactory patients 17 Conclusions : Even though we observed statistically significant reduction of VAS score after injections patients did not seem to be satisfactory.

이물 육아종으로 오인된 심부 열상 이후 발생한 비정상적인 내측 족저 신경의 외상성 신경종: 증례 보고

우승훈,배정연,김태우 대한족부족관절학회 2017 대한족부족관절학회지 Vol.21 No.4

Traumatic neuromas are rare benign tumors that are common after trauma or surgery and are usually accompanied by obvious symp�toms of pain. Most reports show neuromas in the face, neck, and limbs, and the traumatic neuroma of the medial plantar nerve has rarely been reported. We encountered a traumatic neuroma of the medial plantar nerve after a deep laceration mimicking a foreign body granuloma. A small mass lesion was found around plantar aponeurosis with heterogeneous high signal intensity in the T2 fat suppres�sion view and slightly enhanced intensity in the magnetic resonance imaging that suggested a foreign body granuloma. The lesion was diagnosed pathologically as a traumatic neuroma. A satisfactory clinical result was obtained after excision of the traumatic neuroma and burial of the proximal and distal stumps to the adjacent muscle at the secondary operation

Buccinator Myomucosal Flap for Treatment of Osteoradionecrosis of the Mandible

우승훈 대한이비인후과학회 2016 Clinical and Experimental Otorhinolaryngology Vol.9 No.1

The use of a myomucosal flap from the buccinator muscle is a valuable reconstruction method for intraoral defects. In this paper, we report the clinical advantages of using a buccinator myomucosal flap for the treatment of partial mandibular defects caused by osteoradionecrosis. We implemented a buccinator myomucosal flap for the reconstruction of a partial mandibular defect in a 55-year-old man with tonsil cancer and partial mandibular defects caused by osteoradionecrosis. The total operating time was 90 minutes. Twelve months after the reconstruction, the patient remains free of disease. A buccinator myomucosal flap can be used for the reconstruction of partial mandibular defects caused by osteoradionecrosis. It is a reliable method for reconstructing small mandibular defects.

Photodynamic therapy for SNU-80 anaplastic thyroid cancer cells

우승훈,Kun-Woo Kim,Phil-Sang Chung,이상준 대한의학레이저학회 2022 MEDICAL LASERS Vol.11 No.2

Background and ObjectivesAnaplastic thyroid carcinoma (ATC) is one of the lethal human neo-plasms. Photodynamic therapy (PDT) is based on the interaction of a photosensitizer and light with a specific wavelength, and induces destruction of cancer cells. The purpose of this study is to evaluate the effect of the PDT with photofrin on SNU-80 anaplastic thyroid cancer cells.Materials and MethodsAfter PDT, cell viability was measured by MTT assay. The experiments were done at photofrin concentration of 1.6 to 3.2 μg/ml. Subcellular localization of photofrin were observed by ER-TrackerTM and Mito-Tracker®. Hoechst and propidium iodide (PI) double stained cells were analyzed to measure the cellular apoptosis and necrosis using confocal microscope at 4, 8, and 24 hours after laser irradiation. Caspase activation was measured by western blot analysis.ResultsCytotoxicity was increased accordingly to increasing photofrin concen-tration in MTT assay. The photofrin was localized at cytoplasm and mitochondria inside SNU-80 cells. Apoptosis and necrosis cells were increased on confocal microscope, as time after irradiation was progressed. The expression of caspase-3, -9 and poly (ADP-ribose) polymerase (PARP) were detected by Western blot analysis indicating that Photoprin-PDT showed cytotoxicity to anaplastic thyroid cancer cells in dose-dependent pattern.ConclusionPhotofrin-PDT led to in vitro cell death of SNU-80 cells through mito-chondrial mediated apoptosis. PDT could be used as a part of multimodal treatment for ATC.

Treatment of atypical longitudinal vocal polyp with CO2 laser

우승훈 대한의학레이저학회 2022 MEDICAL LASERS Vol.11 No.3

Vocal cord polyps are benign reactive lesions usually resulting from phonotrauma and congenital origins. A 24-year-old female visited the hospital with a husky, breathing voice. The patient had no history of general anesthesia or intubation. Atypical longitudinal vocal cords were identified under laryngoscopy. During the operation, the direct laryngoscope and histological findings revealed an atypical longitudinal polyp of the vocal cords. This paper presents a rare case of a longitudinal vocal polyp removed with a CO2 laser.