Dong Gyu Kim

Seoul National University Hospital, Sŏul, Seoul, South Korea

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Publications (175)389.28 Total impact

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    ABSTRACT: OBJECT There is inconsistency among the perioperative management strategies currently used for chronic subdural hematoma (cSDH). Moreover, postoperative complications such as acute intracranial bleeding and cSDH recurrence affect clinical outcome of cSDH surgery. This study evaluated the risk factors associated with acute intracranial bleeding and cSDH recurrence and identified an effective perioperative strategy for cSDH patients. METHODS A retrospective study of patients who underwent bur hole craniostomy for cSDH between 2008 and 2012 was performed. RESULTS A consecutive series of 303 cSDH patients (234 males and 69 females; mean age 67.17 years) was analyzed. Postoperative acute intracranial bleeding developed in 14 patients (4.57%) within a mean of 3.07 days and recurrence was observed in 37 patients (12.21%) within a mean of 31.69 days (range 10-104 days) after initial bur hole craniostomy. The comorbidities of hematological disease and prior shunt surgery were clinical factors associated with acute bleeding. There was a significant risk of recurrence in patients with diabetes mellitus, but recurrence did not affect the final neurological outcome (p = 0.776). Surgical details, including the number of operative bur holes, saline irrigation of the hematoma cavity, use of a drain, and type of postoperative ambulation, were not significantly associated with outcome. However, a large amount of drainage was associated with postoperative acute bleeding. CONCLUSIONS Bur hole craniostomy is an effective surgical procedure for initial and recurrent cSDH. Patients with hematological disease or a history of prior shunt surgery are at risk for postoperative acute bleeding; therefore, these patients should be carefully monitored to avoid overdrainage. Surgeons should consider informing patients with diabetes mellitus that this comorbidity is associated with an increased likelihood of recurrence.
    Journal of neurosurgery. 02/2015;
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    ABSTRACT: Angiographic findings suggest that central neurocytoma (CN) might originate from neuronal cells of the subventricular zone (SVZ) around the foramen of Monro rather than from the septum pellucidum. The majority of CN cells have neuroblast characteristics. Most importantly, CN-derived tumor spheres have a phenotype of transit-amplifying type C cells, implying that these cells might arise from transformed transit-amplifying type C cells that reside in the SVZ. These CN-derived tumor spheres are also reminiscent of radial glial cells. Immunohistochemical and electrophysiologic studies show that these cells exhibit bipotential neuroglial differentiation in vitro. Copyright © 2015 Elsevier Inc. All rights reserved.
    Neurosurgery Clinics of North America 01/2015; 26(1):31-36. · 1.54 Impact Factor
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    ABSTRACT: Central neurocytoma (CN) is an uncommon, deep-seated tumor of the central nervous system. Optimal treatment strategies and long-term outcomes are not well established. The mainstay of initial treatment CN is total surgical resection whenever possible; however, CNs cannot be resected completely in more than half of patients. Advances in alternative and adjuvant treatments and their role in the treatment of CN is becoming significant. This article provides an overview of the clinical outcomes of various treatment modalities, recent advances, and recommendations for the treatment of CN, emphasizing functional outcomes and the quality of life. Copyright © 2015 Elsevier Inc. All rights reserved.
    Neurosurgery Clinics of North America 01/2015; 26(1):83-90. · 1.54 Impact Factor
  • Dong Gyu Kim, Chul-Kee Park
    Neurosurgery Clinics of North America. 01/2015;
  • Ji Hoon Phi, Dong Gyu Kim
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    ABSTRACT: Central neurocytoma is extremely rare in pediatrics. In a single institute's record, it represents about 0.2% of brain tumors in children. The treatment of central neurocytoma in children is not different from that for adult patients. Surgical resection is the mainstay of treatment. After complete resection, the long-term prognosis is excellent. Adjuvant radiation therapy or radiosurgery may be applied to residual or recurrent tumors. However, the exact indication for each modality should be refined by accumulation of clinical data for this rare disease in children. Copyright © 2015 Elsevier Inc. All rights reserved.
    Neurosurgery Clinics of North America 01/2015; 26(1):105-108. · 1.54 Impact Factor
  • Dong Gyu Kim, Chul-Kee Park
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    ABSTRACT: The establishment and identification of central neurocytoma as a distinct disease entity are invaluable in catalyzing investigations of neuronal differentiation in central nervous system tumors. The discovery of neuronal differentiation in neuroepithelial tumors has been extended to extraventricular tumors and potentially to various glial tumors undergoing neuronal differentiation. Understanding the disease spectrum of neuronal and mixed neuronal-glial tumors is important for deciphering the mechanism of gliomagenesis. Copyright © 2015 Elsevier Inc. All rights reserved.
    Neurosurgery clinics of North America. 01/2015; 26(1):1-4.
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    ABSTRACT: We evaluated the clinical characteristics and factors associated with mortality in very elderly patients ≥ 90 y of age admitted to the ICU. We evaluated age-specific rates of admission and mortality in 16,935 subjects ≥ 18 y old and retrospectively analyzed the clinical data of 155 (0.92%) subjects ≥ 90 y old admitted to the ICU from January 2003 to July 2012. The clinical mortality index was defined as the ICU mortality rate associated with clinical risk factors including poor nutrition, do not resuscitate (DNR) order, pneumonia, chronic renal failure, cancer, mechanical ventilation, use of a vasopressor, and admission from a ward. The mortality rate of ICU subjects ≥ 90 y of age was 32.3%. A Cox's regression hazard model revealed that high glucose (P = .006), poor nutrition (P = .001), high Simplified Acute Physiology Scoring II scores (P < .001), DNR order (P = .002), and vasopressor treatment (P = .03) were independent predictive factors of mortality in subjects ≥ 90 y of age admitted to the ICU. An increasing number of clinical risk factors was associated with progressively higher mortality rates. All subjects with more than 5 risk factors died. The very elderly subjects (≥ 90 y) admitted to the ICU had a higher mortality rate compared with subjects of other ages. High Simplified Acute Physiology Scoring II scores, poor nutritional status, high glucose, use of vasopressors, and DNR orders should be considered as important predictors of mortality in very elderly ICU patients. The level of ICU treatment should be carefully considered in very elderly patients presenting with 5 or more risk factors. Copyright © 2015 by Daedalus Enterprises Inc.
    Respiratory care 11/2014; · 1.84 Impact Factor
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    ABSTRACT: Objective While several prognostic models have been presented in NSCLC patients with brain metastasis, none of these models have included molecular markers as an index. The aim of our study was to evaluate the prognostic value of EGFR mutations and to integrate these EGFR mutations into the prognostic index in NSCLC patients with brain metastasis. Materials and Methods We analyzed retrospectively 292 lung adenocarcinoma patients with brain metastasis. Clinico-pathological features and overall survival (OS) were compared between patients with EGFR mutations and patients with EGFR wild type. EGFR mutation status was integrated with lung specific Graded Prognostic Assessment (GPA) score. Results Among 292 patients, EGFR mutation status was tested in 183 patients. One hundred and five patients (57.4%) had EGFR activating mutations, 14 (7.7%) had EGFR non-activating mutations and 64 (35.0%) had EGFR wild type. OS was significantly longer in patients with EGFR activating mutations than in those with EGFR wild type patients (20.4 vs. 10.1 months, p = 0.002). However, patients with EGFR non-activating mutations did not show superior OS compared with EGFR wild type patients (14.6 vs. 10.1 months, p = 0.83). Multivariate analysis revealed that the presence of EGFR activating mutation is an independent positive prognostic factor for OS (adjusted hazard ratio 0.56, p = 0.002). Conclusions EGFR activating mutations have a prognostic role in lung adenocarcinoma patients with brain metastasis that is independent of other known prognostic factors. The frequency of EGFR mutation was higher than expected. The presence of EGFR activating mutations should be included as an index in the prognostic models for lung adenocarcinoma patients with brain metastasis.
    Lung Cancer 10/2014; · 3.74 Impact Factor
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    ABSTRACT: We investigated the effect of propofol and fentanyl on microelectrode recording (MER) and its clinical applicability during subthalamic nucleus (STN) deep brain stimulation (DBS) surgery. We analyzed 8 patients with Parkinson's disease, underwent bilateral STN DBS with MER. Their left sides were done under awake and then their right sides were done with a continuous infusion of propofol and fentanyl under local anesthesia. The electrode position was evaluated by preoperative MRI and postoperative CT. The clinical outcomes were assessed at six months after surgery. We isolated single unit activities from the left and the right side MERs. There was no significant difference in the mean firing rate between the left side MERs (38.7±16.8 spikes/sec, n=78) and the right side MERs (35.5±17.2 spikes/sec, n=66). The bursting pattern of spikes was more frequently observed in the right STN than in the left STN. All the electrode positions were within the STNs on both sides and the off-time Unified Parkinson's Disease Rating Scale part III scores at six months after surgery decreased by 67% of the preoperative level. In this study, a continuous infusion of propofol and fentanyl did not significantly interfere with the MER signals from the STN. The results of this study suggest that propofol and fentanyl can be used for STN DBS in patients with advanced Parkinson's disease improving the overall experience of the patients.
    Journal of Korean Medical Science 09/2014; 29(9):1278-86. · 1.25 Impact Factor
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    ABSTRACT: A 45-yr-old female patient was admitted with one-month history of headache and progressive left hemiparesis. Brain magnetic resonance imaging (MRI) demonstrated a mass lesion in her right frontal lobe. Her brain tumor was confirmed as a small cell glioblastoma. Her follow-up brain MRI, taken at 8 months after her initial surgery demonstrated tumor recurrence in the right frontal lobe. Contrast-enhanced 7.0T brain magnetic resonance imaging (MRI) was safely performed before surgery and at the time of recurrence. Compared with 1.5T and 3.0T brain MRI, 7.0T MRI showed sharpened images of the brain tumor contexture with detailed anatomical information. The fused images of 7.0T and 1.5T brain MRI taken at the time of recurrence demonstrated no significant discrepancy in the positions of the anterior and the posterior commissures. It is suggested that 7.0T MRI can be safely utilized for better images of the maligant gliomas before and after surgery.
    Journal of Korean Medical Science 07/2014; 29(7):1012-7. · 1.25 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the effectiveness of the extended endoscopic endonasal transsphenoidal approach (TSA) for recurrent or residual craniopharyngiomas, focusing on the extent of tumor resection and complications resulting from surgery at a single institution.
    Acta Neurochirurgica 06/2014; · 1.79 Impact Factor
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    ABSTRACT: Object Neurofibromatosis Type 2 (NF2) is an autosomal-dominant inherited disease, characterized by multiple neoplasia syndromes, including meningioma, schwannoma, glioma, and ependymoma. In this report, the authors present their clinical experience with pediatric NF2 patients. In particular, they focused on the clinical course of vestibular schwannoma (VS), including the natural growth rate, tumor control, and functional hearing outcomes. Methods From May 1988 to June 2012, the authors recruited patients who were younger than 18 years and fulfilled the Manchester criteria. In total, 25 patients were enrolled in this study. The authors analyzed the clinical course of these patients. In addition, they measured the natural growth rate of VS before any treatment in these children with NF2. Then, they evaluated the tumor control rate and functional hearing outcomes after the treatment of VS. Results The mean age at the onset of NF2-related symptoms was 9.9 ± 4.5 years (mean ± SD, range 1-17 years). The mean age at the diagnosis of NF2 was 12.9 ± 2.9 years (range 5-17 years). The mean follow-up period was 89.3 months (range 12-311 months). As initial manifestations, nonvestibular symptoms were frequently observed in pediatric patients with NF2. The mean natural growth rate of VS was 0.33 ± 0.41 cm(3)/year (range 0-1.35 cm(3)/year). The tumor control rate of VS was 35.3% at 3 years after Gamma Knife surgery (GKS). The actuarial rate of useful hearing preservation was 67% in the 1st year and 53% in the 5th year after GKS. Conclusions Clinical manifestations in children with NF2 were highly variable, compared with their adult counterparts. The natural growth rate of VS in children is slow, and this oncological feature may explain the diverse clinical manifestations besides vestibular symptoms in children with NF2. The treatment outcome of GKS for VS in children with NF2 was not favorable compared with previous reports of affected adults.
    Journal of Neurosurgery Pediatrics 04/2014; · 1.63 Impact Factor
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    ABSTRACT: We performed this retrospective study to analyze the outcome of patients with cavernous sinus hemangioma (CSH) after stereotactic radiosurgery (SRS). We analyzed 19 patients with CSHs who were treated with SRS between 1998 and 2011. The median age of the patients was 50 years (range, 35-73 years), and 16 (84.2 %) of the patients were female. SRS was performed as a primary treatment for 18 patients and to treat a residual lesion after surgical resection in one patient. Nine (47.4 %) patients had cranial neuropathies in 14 cranial nerves before SRS, whereas five (26.3 %) patients were initially asymptomatic. The mean volume of the CSHs was 6.1 ± 7.2 cm(3) (range, 0.3-32.3 cm(3)), and the median marginal dose at the 50 % isodose line was 14.5 Gy (range, 11.5-16.0 Gy). The mean follow-up period was 37 months (range, 12-85 months). At the last follow-up, the lesion volume had decreased in all patients. The average tumor volume had decreased to 26 % (range, 0-70 %) of the initial volume at the last follow-up MRI. The first follow-up MRI, performed 6.1 ± 1.0 months after the SRS, showed that the tumor volume had decreased to 41 % (range, 0-88 %) of the initial volume. All 14 of the cranial neuropathies observed before SRS had improved, with complete remission in 12 (85.7 %) cranial nerves and partial remission in two (14.3 %). There were no radiation-induced neuropathies or complications during the follow-up period. SRS appears to be an effective and safe treatment modality for the management of CSHs.
    Journal of Neuro-Oncology 03/2014; · 3.12 Impact Factor
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    ABSTRACT: Patients with tracheostomies requiring prolonged home mechanical ventilation are increasing in number rapidly. A tracheoesophageal fistula is a relatively unusual complication, but this case resulted in a fatal outcome. We describe a tracheoesophageal fistula with tracheal dilation in a 72-year-old female who had a prolonged tracheostomy and nasogastric tube, using a home mechanical ventilator. On enhanced CT images, the tracheostomy tube was well located within the trachea with no abnormal finding. However, chest enhanced CT images obtained 5 months later showed marked circumferential wall thickening of the trachea with tiny ulceration, a markedly increased diameter of the tracheal lumen, and a tracheoesophageal fistula. In patients using home mechanical ventilators, the location and cuff pressure of the tracheostomy tube and the nasogastric tube should be evaluated routinely.
    Korean Journal of Medicine. 01/2014; 87(1):87.
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    ABSTRACT: Mitochondrial dysfunction in dopaminergic neurons of patients with idiopathic and familial Parkinson's disease (PD) is well known although the underlying mechanism is not clear. We established a homogeneous population of human adipose tissue-derived mesenchymal stromal cells (hAD-MSCs) from human adult patients with early-onset hereditary familial Parkin-defect PD as well as late-onset idiopathic PD by immortalizing cells with the hTERT gene to better understand the underlying mechanism of PD. The hAD-MSCs from patients with idiopathic PD were designated as "PD", from patients with Parkin-defect PD as "Parkin" and from patients with pituitary adenomas as "non-PD" in short. The pGRN145 plasmid containing hTERT was introduced to establish telomerase immortalized cells. The established hTERT-immortalized cell lines showed chromosomal aneuploidy sustained stably over two-years. The morphological study of mitochondria in the primary and immortalized hAD-MSCs showed that the mitochondria of the non-PD were normal; however, those of the PD and Parkin were gradually damaged. A striking decrease in mitochondrial complex I, II, and IV activities was observed in the hTERT-immortalized cells from the patients with idiopathic and Parkin-defect PD. Comparative Western blot analyses were performed to investigate the expressions of PD specific marker proteins in the hTERT-immortalized cell lines. This study suggests that the hTERT-immortalized hAD-MSC cell lines established from patients with idiopathic and familial Parkin-defect PD could be good cellular models to evaluate mitochondrial dysfunction to better understand the pathogenesis of PD and to develop early diagnostic markers and effective therapy targets for the treatment of PD.
    Experimental neurobiology. 12/2013; 22(4):283-300.
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    ABSTRACT: The surgical approach for recurrent pituitary adenoma after trans-sphenoidal approach (TSA) is challenging. We report the outcomes of the endoscopic TSA for recurrent pituitary adenoma after microscopic TSA. From February 2010 to February 2013, endoscopic TSA was performed for removal of 30 recurrent pituitary adenomas after microscopic TSA. Twenty-seven (90%) patients had a clinically non-functioning pituitary adenoma. Twenty-four (80%) patients suffered from a visual disturbance related to tumor growth. The clinical features and surgical outcomes were retrospectively analyzed for the ophthalmological, endocrinological, and oncological aspects. The mean tumor volume was 11.7 cm(3), and gross total resection was achieved in 50% of patients. The volumetric analysis based on the postoperative MR showed that the mean extent of resection rates were 90%. Vision was improved in 19 (79%) of 24 patients with visual symptoms, and endocrinological cure was achieved in all of three functioning pituitary adenomas; however, the post-operative follow-up endocrinological examination revealed a new endocrinological deficit in one patient. Two patients required antibiotics management for post-operative meningitis. The endoscopic TSA can be an effective treatment option for recurrent pituitary adenoma after microscopic TSA with acceptable outcome.
    Journal of Korean Neurosurgical Society 10/2013; 54(4):317-322. · 0.52 Impact Factor
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    ABSTRACT: Despite the favorable outcomes of radiosurgery for central neurocytoma (CN), these results are based on case series that included a limited number of patients and short follow-up periods because of the scarcity of CN. Because CN is a benign tumor with an indolent clinical course, long-term follow-up and analysis of failure pattern are required for the establishment of the role of radiosurgery in the management of CN. Twenty consecutive patients (10 patients who received Gamma Knife radiosurgery (GKRS) as a primary treatment and 10 patients who received GKRS as a secondary treatment) with a radiological follow-up period ≥36 months were included in this study. The mean radiological follow-up duration was 100 months (range 43-149 months). The mean tumor volume was 10.4 cm(3) (range 0.4-36.4 cm(3)) and the mean marginal dose was 15.4 Gy (range 9-20 Gy). Local control failure was found in six patients at the last radiological follow-up. Overall actuarial local control rates were 89.5 % at 5 years and 83.1 % at 10 years. The primary GKRS group included two cases with local failure, with cyst formation or local recurrence. In contrast, in the secondary GKRS group, local control failure was found in four cases (including three cases with an "out-of-field recurrence" pattern) and occurred earlier compared with the primary GKRS group. Our study suggests that GKRS could be a primary or secondary treatment option for CN. However, long-term radiological follow-up is mandatory. In particular, more careful consideration during margin delineation and planning procedure is required in the secondary GKRS group.
    Journal of Neuro-Oncology 09/2013; · 3.12 Impact Factor
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    ABSTRACT: As increasing numbers of deep brain stimulation (DBS) procedures are performed, rare abnormal findings on postoperative images that are not attributable to well-known complications are reported. Between 2005 and 2012, we encountered several symptomatic patients with transient abnormal low-attenuation lesions on postoperative computed tomography (CT) scans. The aim of this study was to clarify this rare phenomenon using chronological observations and to suggest a feasible mechanism. In this period, seven (3.2 %) patients displayed transient increased low-attenuation signals, circumferentially surrounding the DBS electrodes and extending into the subcortical white matter. All these patients suffered from unexpected but transient neurological symptoms during the postoperative period. The abnormal low-attenuation lesions only disappeared completely a considerable time after the clinical symptoms had disappeared, without treatment in most patients. We report here our chronological observations of acute brain reactions after DBS procedures, which we believe are neither infectious nor vascular, but are possibly caused by the mechanical breakdown of the blood-brain barrier by microelectrode recordings or by anchored DBS electrodes. These lesions are thought to constitute a self-limiting disorder requiring no further treatment.
    Acta Neurochirurgica 09/2013; · 1.79 Impact Factor
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    ABSTRACT: We investigated the safety and clinical applicability of 7.0 Tesla (T) brain magnetic resonance imaging (MRI) in patients with brain tumors. Twenty-four patients with intraaxial or extraaxial brain tumors were enrolled in this study. 7.0T MRIs of T2*-weighted axial and T1-weighted coronal or sagittal images were obtained and compared with 1.5T brain MRIs. The T2*-weighted images from 7.0T brain MRI revealed detailed microvasculature and the internal contents of supratentorial brain tumors better than that of 1.5T brain MRI. For brain tumors located in parasellar areas or areas adjacent to major cerebral vessels, flow-related artifacts were exaggerated in the 7.0T brain MRIs. For brain tumors adjacent to the skull base, susceptibility artifacts in the interfacing areas of the paranasal sinus and skull base hampered the aquisition of detailed images and information on brain tumors in the 7.0T brain MRIs. This study shows that 7.0T brain MRI can provide detailed information on the intratumoral components and margins in supratentorial brain tumors. Further studies are needed to develop refined MRI protocols for better images of brain tumors located in the skull base, parasellar, and adjacent major cerebrovascular structures.
    Journal of Korean medical science 09/2013; 28(9):1362-72. · 0.84 Impact Factor
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    ABSTRACT: The object of this study was to analyze treatment outcomes and to identify the prognostic factors, with a focus on the role of adjuvant radiotherapy (ART), predicting disease progression in atypical meningiomas. From 1997 to 2011, 83 patients with meningioma were included in this study. All patients were histologically confirmed as atypical meningioma and were treated with surgical resection with or without ART. As primary therapy, 27 patients received surgical resection followed by ART, and 56 received no adjuvant therapy. Of 83 evaluable patients, 55 (66.3 %) patients underwent complete resection. The median ART dose was 61.2 Gy and their median age was 52 years. The 5- and 10-year actuarial overall survival rates were 90.2 and 62.0 %, and the 5- and 10-year progression-free survival (PFS) rates were both 48.0 %, with a median follow-up of 43.0 months. Addition of ART (p = 0.016) and complete tumor resection (p = 0.002) were associated with superior PFS. When stratified to four groups according to resection status and ART, the groups of patient with incomplete resection without ART showed significantly worse PFS compared to other three groups (p < 0.001). In conclusion, surgical resection followed by ART led to lower local tumor progression in patients with atypical meningioma defined by the updated 2000/2007 WHO classification. Our results may contribute to the routine use of ART, especially after incomplete resection, until the outcomes of ongoing prospective trials are available.
    Journal of Neuro-Oncology 08/2013; · 3.12 Impact Factor

Publication Stats

2k Citations
389.28 Total Impact Points

Institutions

  • 1998–2015
    • Seoul National University Hospital
      • • Department of Neurosurgery
      • • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2009–2012
    • Dongguk University
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
    • Seoul National University Bundang Hospital
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
  • 2011
    • Kosin University
      • College of Medicine
      Pusan, Busan, South Korea
  • 2009–2011
    • Hallym University Medical Center
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2003–2011
    • Seoul National University
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
  • 2008–2009
    • Inje University Paik Hospital
      Sŏul, Seoul, South Korea
  • 2007–2009
    • Yeungnam University
      • Department of Rehabillitation Medicine
      Daikyū, Daegu, South Korea
  • 2006
    • Kangwon National University Hospital
      Shunsen, Gangwon, South Korea
  • 2004–2006
    • Hallym University
      • College of Medicine
      Sŏul, Seoul, South Korea
    • Seoul Women's University
      Sŏul, Seoul, South Korea
  • 2004–2005
    • National Veterinary Research Quarantine Service
      Sŏul, Seoul, South Korea
  • 2003–2005
    • National Cancer Center Korea
      Kōyō, Gyeonggi Province, South Korea