• Journal of Korean Neurosurgical Society
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• v.56 no.1
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• pp.16-20
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• 2014

Objective : Two-dimensional fluoroscopy-based computerized navigation for the placement of pedicle screws offers the advantage of using stored patient-specific imaging data in providing real-time guidance during screw placement. The study aimed to describe the accuracy and reliability of a fluoroscopy-based navigation system for pedicle screw insertion. Methods : A total of 477 pedicle screws were inserted in the lower back of 96 consecutive patients between October 2007 and June 2012 using fluoroscopy-based computer-assisted surgery. The accuracy of screw placement was evaluated using a sophisticated computed tomography protocol. Results : Of the 477 pedicle screws, 461 (96.7%) were judged to be inserted correctly. Frank screw misplacement [16 screws (3.3%)] was observed in 15 patients. Of these, 8 were classified as minimally misplaced (${\leq}2mm$); 3, as moderately misplaced (2.1-4 mm); and 5, as severely misplaced (>4 mm). No complications, including nerve root injury, cerebrospinal fluid leakage, or internal organ injury, were observed in any of the patients. Conclusion : The accuracy of pedicle screw placement using a fluoroscopy-based computer navigation system was observed to be superior to that obtained with conventional techniques.

• Korean Journal of Computational Design and Engineering
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• v.15 no.3
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• pp.234-242
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• 2010

3D CAD technology has been extended to a medical area including dental clinic beyond industrial design. The 2D images obtained by CT(Computerized Tomography) and MRI(Magnetic Resonance Imaging) are not intuitive, and thus the volume rendering technique, which transforms 2D data into 3D anatomic information, has been in practical use. This paper has focused on a method and its implementation for forming 3D geometric surface model from laminated CT images of the pubis. The implemented system could support a dental clinic to observe and examine the status of a patient's pubis before implant surgery. The supplement of 3D implant model would help dental surgeons settle operation plans more safely and confidently. It also would be utilized with teaching materials for a practice and training.

• Journal of Biomedical Engineering Research
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• v.28 no.3
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• pp.332-337
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• 2007

In the early twenty-first century, minimally invasive surgery is the mainstay of various kinds of surgical fields. Surgeons gave percutaneously surgical treatment of the screw directly using a fluoroscopic view in the past. The latest date, they began to operate the fractured carpal bone surgery using Computerized Tomography (CT). Carpal bones composed of wrist joint consist of eight small bones which have hexahedron and sponge shape. Because of these shape, it is difficult to grasp the shape of carpal bones using only CT image data. Although several image segmentation studies have been conducted with carpal bone CT image data, more studies about carpal bone using CT data are still required. Especially, to apply the software implemented from the studies to clinical fIeld, the outcomes should be user friendly and very accurate. To satisfy those conditions, we propose modified multi-seed region growing segmentation method which uses simple threshold and the canny edge detector for finding edge information more accurately. This method is able to use very easily and gives us high accuracy and high speed for extracting the edge information of carpal bones. Especially, using multi-seed points, multi-bone objects of the carpal bone are extracted simultaneously.

• Journal of Biomedical Engineering Research
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• v.7 no.2
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• pp.113-116
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• 1986

We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.175-176
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• 2006

The aim of the 3D medical imaging is to facilitate the creation of clinically usable image-based algorithm. Clinically usable imaging algorithm for image analysis requires a high degree of interaction to verify and correct results from registration algorithms, such as the Insight Toolkit (ITK) and the Visualization Toolkit (VTK) which are the class libraries. ITK provides segmentation algorithms and VTK has powerful 3D visualization. However, to apply those libraries to the medical images such as Computerized Tomography (CT), the algorithm based on the interactive construction and modification of data objects are necessary. In this paper we showed the 3D registration about mandibular premolar of human teeth acquired by micro-CT scanner. Also, we used the ITK to find the contour of pulp layer of premolar, furthermore, the 3D imaging was visualized with VTK designed to create one kind of view on the data of 3D visualization. Finally, we evaluated that the volume model of pulp layer would be useful for the tooth morphology in dental medicine.

• The Korean Journal of Emergency Medical Services
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• v.24 no.2
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• pp.99-109
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• 2020

Purpose: Alcohol intoxication is frequently observed in patients with brain hemorrhage. The purpose of this study was to determine whether intoxication affects the Korean Triage and Acuity Stage (KTAS) level and the emergency medical process in emergency departments. Methods: This study was a retrospective observational study enrolled 253 brain hemorrhage patients (47 of those intoxicated) who visited the emergency medical center on public EMS ambulance from January. 1, 2017 to April, 30, 2019. Data were collected through the electronic medical record (EMR). KTAS level and time to computerized tomography (CT) were compared to evaluate whether inebriation affects care and examination processes. All data were analyzed using SPSS program. Results: Of the 47 patients intoxicated patients, 85.1% were male, and 74.5% accompanied by trauma. Initial KTAS level showed significant differences (77.2%; p=.000) when the level 3,4 was not drunk. The average time taken from triage to CT scans showed a significant difference of 24.81±23.72 (min) when the drunken state was not 58.38±56.54 (min)(p=.000). Conclusion: In patients with brain hemorrhage admitted to ED from public EMS, undertriage and delay after initial assessment were detected in inebriated patients. Careful initial evaluation and prompt medical response should be considered for patients transported by EMS.

• Herbal Formula Science
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• v.14 no.2
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• pp.45-56
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• 2006

Objectives : We evaluated anti-hyperlipidemia effect of Gyeongshinganjeehwan (GGEx) in high fat induced obese male micro-pigs. Methods : 7 month-old micro-pigs are fed with normal (n = 3) or high fat diet (n = 18) for 12 weeks. The pig revealed obesity in high fat diet were divided into 2 groups (n = 5 each) and vehicle (OMP) and Gyeongshingangjeehwan (GGEx, 616.7 mg/kg/day) were administrated for 1 month. We monitored the changes in body weight and measured plasma cholesterol, triglyceride, free fatty acid, GOT and, GPT after 1 month. The visceral fat were measured with computerized tomography and weights of various organs were measured after sacrifice. Results : 1. GGEx group had significantly reduced body weight gain than obese control group in statistics. 2. GGEx group didn't significantly differ from obese control group in blood total cholesterol, blood LDL-cholesterol, blood triglyceride. but it's data were similar to normal control group. 3. GGEx group had prominantly reduced visceral fat than obese control group in computerized tomography. 4. Blood GOT and GPT didn't differ from between groups. The organ weight were not significant different. And it is normal in size and colour of visceral organs. Conclusions : It is concluded that GGEx has anti-hyperlipidemia effect by improving visceral fat and access to security.

• Journal of Korean Neurosurgical Society
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• v.44 no.1
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• pp.15-18
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• 2008

Objective : C2 laminar screw fixation is considered as an excellent alternative to Magerl's transfacetal approach or Harms construct for the atlantoaxial stabilization. However, to our knowledge, there is no report on the feasibility of the new approach to Korean population. We investigated morphometric parameters of the dorsal arch of the C2 to provide the quantitative data for the feasibility of laminar screw fixation. Methods : One-hundred-and-two patients' cervical computed tomography had been reconstructed and investigated on the anatomical parameters related with C2 laminar screw placement. Sixty patients were male and forty-two patients were female. Measurements included the laminar thickness and slope, spino-laminar angle, and maximal screw length. Results : Ages ranged from 20 to 81 and the mean age was 48.4. Mean laminar thickness was 5.7 mm (${\pm}1.0$) (5.8 mm in male and 5.4 mm in female). Fifty-one patients (50%) had a laminar thickness smaller than 5.5 mm at least unilaterally, therefore the patients were considered as inappropriate candidates for the laminar screw fixation in the smaller side of the laminae. Mean value of maximal length of screw was 33.3 mm (34.3 mm in male and 31.9 mm in female). Mean spino-laminar angle was $43.2^{\circ}$ and mean slope angle was $32.9^{\circ}$. Conclusion : Half of patients had inappropriate laminar profiles to accommodate a 3.5 mm screw in at least one side of the axis. The three-dimensional computed tomography reconstruction is mandatory for the preoperative assessment for the feasibility of the C2 lamina.

• Journal of the Korean Society of Radiology
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• v.2 no.3
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• pp.5-9
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• 2008

In the computerized tomography(CT), various filters are using in the reconstruction algorithm to reduce or eliminate the artifacts which are intrinsically induced by the imperfection of mathematical methods for reconstruction, lack of real informations about anatomic structures in the projection image, errors in data acquisition and so on. Hann filter was used to evaluate the filter effects on the elimination of reconstruction artifact in the CT image. The quantitative study was done by changing cut-off frequency of Hann filter from 0.1 to 0.9 with frequency increasement by 0.2. NPS analysis was fulfilled for the quantitative evaluation of filter effect.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.447-450
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• 2012

Video-assisted thoracic surgery (VATS) has been recommended as more optimal surgical technique than traditional thoracotomy for lobectomy in lung cancer, but it is not well defined. Here, we compared VATS and traditional thoracotomy based on clinical data. From November 2008 to November 2010, 180 patients underwent lobectomy for non-small-cell lung cancer (NSCL) identified by computerized tomography. Of them, 83 cases were performed with VATS and 97 by thoracotomy. Clinical parameters, consisting of blood loss, operating time, number of lymph node dissection, days of pleural cavity drainage, and length of stay were recorded and evaluated with t test. No significant difference was observed between the VATS and thoracotomy groups in the average intraoperative blood loss, number of lymph node dissections, and days of pleural cavity drainage. While the average operating time in the VATS group was significantly longer than that in thoracotomy group, recurrence was only present in one case, as opposed to 7 cases in the thoracotomy group In conclusion, similar therapeutic effects were demonstrated in VATS and thoracotomy for NSCL. However, VATS lobectomy was associated with fewer complications, recurrence and shorter length of stay.