• Journal of Trauma and Injury
• /
• 제32권2호
• /
• pp.71-79
• /
• 2019

Purpose: Recent developments in minimally invasive techniques have the potential to reduce surgical morbidity, promote patient recovery, accelerate surgical procedures, and thus improve cost-effectiveness in case management. In this study, we compared the treatment efficacy and results of supraorbital keyhole approach (SOKA) with those of conventional unilateral frontal craniotomy (CUFC) for traumatic intracerebral hemorrhage (TICH) in the frontal lobe. Methods: We analyzed the data of 38 patients who underwent CUFC (n=30) and SOKA (n=8) and retrospectively reviewed their medical records and radiological findings. Furthermore, we tried to identify the best surgical method for such lesions by including patients who underwent burr hole aspiration and drainage (BHAD) (n=9) under local anesthesia due to various circumstances. Results: The difference in the initial Glasgow coma scale score, operative time, and length of hospitalization between the CUFC and SOKA were statistically significant. All radiological features between the two groups including associated skull fracture, amount of pre- and postoperative hematoma, percentage of complete hematoma removal, pre- and postoperative midline shifting of the hematoma, and development of postoperative delayed hematoma were not statistically significant. Our experience of 46 patients with TICH in the frontal lobe with any of the three different surgical methods including BHAD enabled us to obtain valuable findings. Conclusions: Although it is difficult to insist that one particular approach is more useful than the other, we are confident that SOKA will have more advantages over CUFC in carefully selected patients with frontal TICH depending on the surgical experience of a neurosurgeon.

• 대한치과교정학회지
• /
• 제32권1호통권90호
• /
• pp.9-18
• /
• 2002

일반적으로 치조성 양악전돌증의 치료는 환자의 나이나 골격 부조화의 원인, 심도 등에 따라 다른데, 환자의 성장이 이미 완료되고 골격적 부조화의 점도가 심하지 않은 경우에는 치아의 이동만으로 문제를 해소하는 교정적인 절충치료를 행하게 되며 심미성의 증진을 위해서는 소구치, 특히 제1소구치 발치가 적절한 선택일 수 있다. 제1소구치의 발치 후 전치부의 En Masse 견인시 이용되고 있는 double keyhole loop(이하 DKHL로 약함)에는 4개의 루프가 있어 발치 공간 폐쇄시 견치 치관의 원심경사를 조절하고 구치 치관이 근심측으로 경사되는 것을 막아 교합평면의 굴곡을 방지하는 효과가 있는 한편 견치의 회전을 조절할 수 있도록 설계되어 있다. 이 연구는 I급 치조성 양악전돌증 및 II급 1류 부정교합이 있는 성인환자를 대상으로 상, 하악 6전치를 후방이동시킴으로써 연조직의 변화를 가져와 심미적으로 좋은 치료의 결과를 얻기 위해 상악 제1소구치를 발거하여 DKHL에 의해 치료가 완료된 환자의 측모두부방사선사진에서 치료 전, 후의 골격적인 변화와 치아치조영역의 변화를 알아보기 위해 시행되었고, 다음의 결론을 얻었다. 1. DKHL에 의한 치료 전, 후의 골격적인 변화는 SNB의 감소경향(0.49 ${\pm}$ 0.87$^{\circ}$ , p<0.05)과 PTFH의 증가경향(0.50 ${\pm}$ 0.8 mn, p<0.05)을 제외하고는 통계적으로 유의한 변화를 나타내지 않았고 주된 변화는 치아치조영역에서 일어났다. 2. 치료 후 치아치조영역에서는 절치간각을 제외한 모든 계측항목에서 통계적으로 유의할 만한 감소를 보였다. 3. 상하순의 돌출도 모두 유의성 있는 감소를 나타내었다. 4. 상악 전치의 치관은 통계적으로 유의할 만한 후방이동(7.08 ${\pm}$ 2.14 mm, p<0.01)을 보였고, 상악 전치의 치근에서는 통계적으로 유의할 만한 수직고경의 감소(2.38 ${\pm}$ 1.15 mm, p<0.01)를 보였다. 5. 상악 구치의 치관, 치근 모두에서 통계적으로 유의할 만한 전방이동(2.48 ${\pm}$ 0.99 mm, 2.05 ${\pm}$ 0.91 mm,p<0.01)을 보였다.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.612-619
• /
• 2002

The dynamic behavior of Al-Mg alloys plasma was very unstable and this instability was closely related to the unstable motion of keyhole during laser irradiation. The keyhole fluctuated both in size and shape and its fluctuation period was about 440 ${\mu}{\textrm}{m}$. This instability has been estimated to be caused by the evaporation phenomena of metals with different boiling point and latent heats of vaporization. Therefore, the authors have conducted the spectroscopic diagnostics of plasma induced in the pulsed YAG laser welding of Al-Mg alloys in air and argon atmospheres. In the air environment, the identified spectra were atomic lines of Al, Mg, Cr, Mn, Cu, Fe and Zn, and singly ionized Mg line, as well as strong molecular spectrum of AlO, MgO and AIH. It was confirmed that the resonant lines of Al and Mg were strongly self-absorbed, in particular in the vicinity of pool surface. The self-absorption of atomic Mg line was more eminent in alloys containing higher Mg. These facts showed that the laser-induced plasma was relatively a low temperature and high density metallic vapor. The intensities of molecular spectra of AlO and MgO were different each other depending on the power density of laser beam. Under the low power density irradiation condition, the MgO band spectra were predominant in intensity, while the AlO spectra became much stronger in higher power density. In argon atmosphere the band spectra of MgO and AlO completely vanished, but AlH molecular spectra was detected clearly. The hydrogen source was presumably the hydrogen solved in the base Metal, absorbed water on the surface oxide layer or H$_2$ and $H_2O$ in the shielding gas. The temporal change in spectral line intensities was quite similar to the fluctuation of keyhole. The time average plasma temperature at 1 mm high above the surface of A5083 alloy was determined by the Boltzmann plot method of atomic Cr lines of different excitation energy. The obtained electron temperature was 3, 280$\pm$150 K which was about 500 K higher than the boiling point of pure aluminum. The electron number density was determined by measuring the relative intensities of the spectra1lines of atomic and singly ionized Magnesium, and the obtained value was 1.85 x 1019 1/㎥.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제42권
• /
• pp.6.1-6.6
• /
• 2020

Background: Various types of miniplates have been developed and used for the reduction of facial bone fractures. We introduced Yang's Keyhole (YK) plate, and reported on its short-term stability. The purpose of this study was to evaluate the long-term stability of the YK plate, as a follow-up study, by examining the patients who had used the YK plate among the patients with the reduction of mandible fractures and who visited for plate removal. Methods: We reviewed the medical records of 16 patients who underwent mandibular fracture fixation using a YK plate (group I) and 17 patients who underwent mandibular fracture fixation using a conventional plate (group II). Assessment was then made on malunion, occlusal stability, discomfort during the application, and clinical symptoms. Results: From January 2015 to December 2017, a total of 36 patients underwent mandibular fracture surgery using a YK plate. A total of 16 patients received plate removal. Among them, 15 were male and 1 female. The average age was 26 years. The applied surgical sites were the 12 on mandibular angle, 4 on mandibular symphysis, and 2 on subcondyle. The application period of YK plate was an average of 335 days. During the same period, 45 people underwent surgery on the conventional plate. A total of 17 patients received plate removal. Among them, 15 were male and 2 females. The average age was 36 years. The applied surgical sites were the 8 on mandibular angle, 4 on mandibular symphysis, and 2 on subcondyle. The application period of the conventional plate was an average of 349 days. No malocclusion occurred at the time of removal, and occlusion was stable. No patient complained of joint disease or discomfort. Conclusion: The YK plate system, in which the screw was first inserted and the plate was applied, for clinical convenience did not cause any particular problem and no significant difference from the conventional plate.

• 대한자기공명의과학회:학술대회논문집
• /
• 대한자기공명의과학회 2007년도 학술대회
• /
• pp.44-44
• /
• 2007

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2003년도 추계학술발표대회 개요집
• /
• pp.52-54
• /
• 2003

In automotive industry, light weight vehicle is one of issues because of air pollution. Therefore, automotive manufacturers have tried to apply light materials such as aluminum to car body. Welding aluminum using laser has some advantages good weld quality and high productivity. In this study, light emission which is generated in aluminum 6k21 welding with laser is measured using photodiodes. Analysis of relationship between sensor signals of welding variables and formation of keyhole and plasma is performed.

• 한국레이저가공학회지
• /
• 제5권3호
• /
• pp.21-30
• /
• 2002

In automotive industry, the studies about light weight vehicle and improving the productivity have been accomplished. For that, TRIP steel was developed and research for the laser welding process have been performed. In this study, the monitoring system using photodiode was developed for laser welding process of TRIP steel. With measuring light, neural network model for estimating bead width and tensile strength was made and weld quality classification algorithm was formulated with fuzzy inference method.

• Journal of Welding and Joining
• /
• 제17권3호
• /
• pp.26-35
• /
• 1999

On the laser weld production line, a slight alteration of the welding condition changes the bead size and the strength of the weldment. The measurement system is produced by using three photo-diodes for detection of the plasma and spatter signal in $CO_2$ laser welding. The relationship between the sensor signals of plasma or spatter and the bead shape, and the mechanism of the plasma and spatter were analyzed for the bead size estimation. The penetration depth and the bead width were estimated using the multiple regression analysis.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
• /
• pp.94-96
• /
• 2005

Welding process of ultra thin stainless steel foil was investigated using a single mode Yb-fiber laser with a CW maximum output power 40W. In micro welding, critical power density for keyhole welding was 1 to 2 orders larger higher than in macro-welding due to larger thermal conduction, extremely high speed welding becomes possible.

• 한국산학기술학회논문지
• /
• 제13권12호
• /
• pp.6208-6214
• /
• 2012

해양미세조류 유래 독성물질에 대한 이해와 활용에 있어서 가장 중요하지만 간과되고 있는 부분은 독성물질을 검출할 수 있는 빠르고, 쉽고 경제적인 검출기술을 개발하는 것이다. 이 논문에서 우리는 삭시톡신(STX)에 대한 항체를 생산하였다. 헤모시아닌(mariculture keyhole limpet hemocyanin, mcKLH)과 오브알부민(ovalbumin, OVA)을 운반단백질로 사용하였다. 면역반응을 위해서 mcKLH-STX 결합체를 BALB/c 쥐에 복강주사하였다. 채혈 후 항-STX 항혈청을 분리하였다. 항혈청의 역가분석을 위하여 유리 STX와 OVA-STX로 코팅된 microtiter plate를 이용하여 간접 ELISA 실시하였다. 발색반응을 위한 이차항체로는 goat anti-mouse IgG-phosphatase conjugate가 사용되었다. 항-STX 항혈청은 OVA-STX와 유리 STX에 특이적으로 반응하였다. 항-STX 항혈청의 민감도는 매우 높았으며, STX를 위한 검출한계는 약 64.9 ng/kg이었다.