• 한국정밀공학회지
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• 제21권6호
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• pp.188-196
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• 2004

The objective of this paper is to propose a new technology of the orthopaedic surgery using the combination of reverse engineering (RE) based on CT data and rapid prototyping (RP). The proposed technology utilizes symmetrical characteristics of the human body and capability of the combination of RE and RP, which rapidly manufactures three-dimensional parts from CT data. The original .stl data of injured extents are generated from the mirror transformation of .stl file fur uninjured extents. The physical shape before injuring is manufactured from RP using the original .stl data. Subsequently, pre-operative planning, such as a selection of proper implants, preforming of the implant, a decision of fixation locations and an insert position for the implant, an estimation of the invasive size, and pre-education of operators are performed using the physical shape. In order to examine the applicability and the efficiency of the proposed surgical technology, various case studies, such as a distal tibia commented fracture, a proximal tibia plateau fracture and an iliac wing fracture of pelvis, are carried out. From the results of case studies, it has been shown that the proposed technology is an effective surgical tool of the orthopaedic surgery reducing the operational time, the operational cost, the radiation exposure of the patient and operators, and morbidity. In addition, the proposed technology could improve the accuracy of operation and the speed of rehabilitation.

• 중환자간호학회지
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• 제12권1호
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• pp.57-70
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• 2019

Purpose : The purpose of this study was to identify the risk factors for falls in tertiary hospital inpatients and to suggest data for developing a nursing intervention program for preventing falls. Methods: Data were collected between January 1, 2017, to December 31, 2017. Kaplan-Meier estimation was used to measure the survival rate, and the log-rank test was used for the differences between the fall group and the non-fall group. The Cox proportional hazards model was used to identify the risk factors for falls. Results: The incidence rate of falls for the inpatients was 1.2 cases per 1,000 days of hospitalization. The risk factors for falls were more likely to be found among those who were aged ${\geq}81$, had not undergone surgery, had poor joint motion, had unsteady gait, needed help or supervision, used assistive devices, had comorbidity, and took at least two drugs. Conclusion: For the inpatients, the risk factors for falls included age, surgery, comorbidity, medication that could change mobility, joint motion, and use of patient care equipment. It is necessary to give special attention to inpatients who have any of these risk factors and to develop a falls risk assessment tool.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1992년도 추계학술대회논문집
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• pp.54-62
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• 1992

This work has been directed at studying and developing a prototype Computer Aided Design(CAD) tool to be used for planning tendon paths in hand reconstructive surgery. The application of CAD to rehabilitative surgery of the hand is a new field of endeavor. There are currently no existing systems designed to assist the orthopedic surgeon in planning these complex peocedures. Additionally, orthopedic surgeons are not trained in mechanics, kinematics, math modeling, or the use of computers. It was also our intent to study the mechanisms and the efficacy of the application of CAD techniques to this important aspect of hand surgery. The following advances are reported here: Interactive 3D tendon path definition tools., Software to calculate tendon excursion from an arbitrary tendon path crossing any number of joints., A model to interactively compute and display the foirces in muscle and tendon., A workstation environment to help surgeons evaluate the consequences of a simulated tendon transfer operation when a tendon is lengthened, rerouted, or reattached in a mew location., It also has been one of the primary concerns in this work that an interactive graphical surgical workstation must present a natural, user-friendly environment to the orthopedic durgeon user. The surgical workstation must ultimately aid the surgeon in helping his patient or in doing his work more efficiently or more reliably.

• Nuclear Engineering and Technology
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• 제55권10호
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• pp.3844-3853
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• 2023

Although radiation and chemotherapy methods for cancer therapy have advanced significantly, surgical resection is still recommended for most cancers. Therefore, intraoperative imaging studies have emerged as a surgical tool for identifying tumor margins. Intraoperative imaging has been examined using conventional imaging devices, such as optical near-infrared probes, gamma probes, and ultrasound devices. However, each modality has its limitations, such as depth penetration and spatial resolution. To overcome these limitations, hybrid imaging modalities and tracer studies are being developed. In a previous study, a multi-modal laparoscope with silicon photo-multiplier (SiPM)-based gamma detection acquired a 1 s interval gamma image. However, improvements in the near-infrared fluorophore (NIRF) signal intensity and gamma image central defects are needed to further evaluate the usefulness of multi-modal systems. In this study, an attempt was made to change the NIRF image acquisition method and the SiPM-based gamma detector to improve the source detection ability and reduce the image acquisition time. The performance of the multi-modal system using a complementary metal oxide semiconductor and modified SiPM gamma detector was evaluated in a phantom test. In future studies, a multi-modal system will be further optimized for pilot preclinical studies.

• Journal of Trauma and Injury
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• 제24권2호
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• pp.136-142
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• 2011

Purpose: Blunt pancreatic injury has a high mortality rate, especially if adequate management is delayed. Although many guidelines exist for diagnosis and treatment, there is no consensus to date. Therefore, we analyzed the role of endoscopic retrograde cholangiopancreatography (ERCP) as a diagnostic and therapeutic tool for the treatment of traumatic pancreatic injury. Methods: We retrospectively reviewed the electronic medical records (EMR) database at Asan Medical Center (Seoul, South Korea) to identify all patients diagnosed with trauma to the pancreas between June 2003 and December 2010. Clinical and operative findings, CT (computed tomography) images, and ERCP findings were assessed. Results: A total of 40 patients were evaluated in this study. Of these, 14 patients underwent diagnostic ERCP, and 26 did not. Of the 14 patients who underwent diagnostic ERCP, 5 were found to have normal pancreatic ducts, thereby preventing a needless laparotomy in these patients. Of the patients diagnosed with ductal injury, four were treated with endoscopic intervention, and four underwent an exploratory laparotomy. The remaining patient was treated with radiologic intervention (percutaneous drainage) to manage pancreatic pseudocyst formation. Conclusion: Our findings suggest that ERCP is a beneficial diagnostic and therapeutic modality for the treatment of traumatic pancreatic injury.

• Journal of Korean Neurosurgical Society
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• 제29권7호
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• pp.891-898
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• 2000

Objective : It is difficult to differentiate intramedullary spinal cord tumors preoperatively from non-neoplastic pathologies in patients presenting as non-compressive myelopathies in magnetic resonance imaging(MRI). In this report, the authors reviewed nonneoplastic intramedullary spinal cord lesions preoperatively diagnosed as tumors and discussed their clinical and radiological characteristics and usefulness of surgical intervention. Methods : From January, 1985 to January, 1999, authors experienced eight non-neoplastic pathologies mimicking intramedullary spinal cord tumors and analysed their medical records, radiological findings and histopathological specimens retrospectively. Results : There were five males and three females and the duration of symptoms were from two to 20 months(mean, 9.8 months). The location of lesions were four cervical, one cervicothoracic and three thoracic. All patients manifested sensory abnormality, seven motor weakness, and six bladder symptom. All cases had swollen spinal cords and increased signal intensities in spin-echo sequences. Six cases showed contrast enhancement : four cases were focal and two diffuse. Under the impression of intramedullary tumors, the patients were operated upon. Final diagnoses on the base of clinical and pathologic finding were : three subacute necrotizing myelopathies, two multiple scleroses, two myelopathy of unknown etiology. One case showed no gross abnormality in surgical field in spite of adequate exposure of the lesion, so biopsy was not performed. In that case, postoperative MRI revealed spontaneous resolution of the lesion. Conclusion : MRI is invaluable diagnostic tool in screening myelopathies. However, its high sensitivity and lack of specificity make difficulty in preoperative differential diagnosis of non-compressive myelopathies. Although no surgical morbidity occurred in our series, we sometimes failed to confirm definite diagnosis even with biopsy. In such a circumstance, long-term follow up is needed.

• Journal of Korean Neurosurgical Society
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• 제63권3호
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• pp.346-357
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• 2020

During the follow-up period after surgery for spinal dysraphism, a certain portion of patients show neurological deterioration and its secondary phenomena, such as motor, sensory or sphincter changes, foot and spinal deformities, pain, and spasticity. These clinical manifestations are caused by tethering effects on the neural structures at the site of previous operation. The widespread recognition of retethering drew the attention of medical professionals of various specialties because of its incidence, which is not low when surveillance is adequate, and its progressive nature. This article reviews the literature on the incidence and timing of deterioration, predisposing factors for retethering, clinical manifestations, diagnosis, surgical treatment and its complications, clinical outcomes, prognostic factors after retethering surgery and preventive measures of retethering. Current practice and opinions of Seoul National University Children's Hospital team were added in some parts. The literature shows a wide range of data regarding the incidence, rate and degree of surgical complications and long-term outcomes. The method of prevention is still one of the main topics of this entity. Although alternatives such as spinal column shortening were introduced, re-untethering by conventional surgical methods remains the current main management tool. Re-untethering surgery is a much more difficult task than primary untethering surgery. Updated publications include strong skepticism on re-untethering surgery in a certain group of patients, though it is from a minority of research groups. For all of the abovementioned reasons, new information and ideas on the early diagnosis, treatment and prevention of retethering are critically necessary in this era.

• Journal of Korean Neurosurgical Society
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• 제29권5호
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• pp.628-634
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• 2000

Objective : The introduction of MRI makes it easy to detect multiple lumbar disc herniation. However, MRI is not a physiologic test for detecting the symptomatic level. For the surgical plan, it is very important to determine the symtomatic level among the multiple lumbar disc herniation. In this regard, we studied diagnostic significance of discography on multiple lumbar disc herniation in determining the symptomatic level. Method and Material : We retrospectvely analyzed the discographic and clinical findings of 121 patients with multiple lumbar disc herniation for investigating the diagnostic availability of discography. All were surgically treated from January 1995 through May 1998. Result : Discography provocated the same pain as usual symptom in 99 out of 121 patients(81.8%). Compared with surgical findings, the diagnostic accuracy of the discography in multiple lumbar disc herniation was 75.6%, sensitivity was 64.6%, and specificity 87.2%. There was no correlation between the pain provocation of discography and the extent of annular degeneration on CT/discogram. The pain provocation showed good correlation with the extent of annular disruption on CT/discogram. The rate of same result(correlation rate) between the discography and D.I.T.I was 81.4% in multiple lumbar disc herniation patients with unilateral leg pain. Conclusion : These results indicate that in multiple lumbar disc herniation, the discography is considered useful diagnostic tool to determine the symptomatic level and to decide the surgical plan.

• Journal of Periodontal and Implant Science
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• 제48권5호
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• pp.274-283
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• 2018

Purpose: Numerous indices have been proposed to analyse wound healing in oral soft tissues, but each has specific shortcomings. A new method of analysis, the Early Wound Healing Score (EHS), was evaluated in the present study. The aim was to assess more accurately early healing by primary intention of surgical incisions in periodontal soft tissues. Methods: Twenty-one patients were treated with different surgical procedures comprising 1 or 2 vertical releasing incisions as part of a surgical access flap. Twenty-four hours after surgery, early wound healing at the vertical releasing incisions was assessed using the EHS. This score assessed clinical signs of re-epithelialization (CSR), clinical signs of haemostasis (CSH), and clinical signs of inflammation (CSI). Since complete wound epithelialization was the main outcome, the CSR score was weighted to be 60% of the total final score. Accordingly, a score of 0, 3, or 6 points was possible for the assessment of CSR, whereas scores of 0, 1, or 2 points were possible for CSH and CSI. Higher values indicated better healing. Accordingly, the score for ideal early wound healing was 10. Results: Thirty vertical releasing incisions were assessed in 21 patients. At 24 hours after incision, 16 vertical releasing incisions (53.33%) received the maximum score of CSR, while 6 cases (20%) received an EHS of 10. None of the cases received 0 points. Conclusion: The EHS system may be a useful tool for assessing early wound healing in periodontal soft tissue by primary intention after surgery.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3031-3035
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• 2012

Background: Though open surgical biopsy is the procedure of choice for the diagnosis of bone tumors, many disadvantages are associated with this approach. The present study was undertaken to evaluate the role of fine needle aspiration cytology (FNAC) as a diagnostic tool in cases of bony tumors and tumor-like lesions which may be conducted in centers where facilities for surgical biopsies are inadequate. Methods: The study population consisted of 51 cases presenting with a skeletal mass. After clinical evaluation, radiological correlation was done to assess the nature and extent of each lesion. Fine needle aspiration was performed aseptically and smears were prepared. Patients subsequently underwent open surgical biopsy and tissue samples were obtained for histopathological examination. Standard statistical methods were applied for analysis of data. Results: Adequate material was not obtained even after repeated aspiration in seven cases, six of which were benign. Among the remaining 44 cases, diagnosis of malignancy was correctly provided in 28 (93.3%) out of 30 cases and categorical diagnosis in 20 (66.67%). Interpretation of cytology was more difficult in cases of benign and tumor-like lesions, with a categorical opinion only possible in seven (50%) cases. Statistical analysis showed FNAC with malignant tumors to have high sensitivity (93.3%), specificity (92.9%) and positive predictive value of 96.6%, whereas the negative predictive value was 86.7%. Conclusion: FNAC should be included in the diagnostic workup of a skeletal tumor because of its simplicity and reliability. However, a definitive pathologic diagnosis heavily depends on compatible clinical and radiologic features which can only be accomplished by teamwork. The cytological technique applied in this study could detect many bone tumors and tumor-like conditions and appears particularly suitable as a diagnostic technique for rural regions of India as other developing countries.