Sun Ha Paek

Seoul National University Hospital, Sŏul, Seoul, South Korea

Are you Sun Ha Paek?

Claim your profile

Publications (216)589.81 Total impact

  • [Show abstract] [Hide abstract]
    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;
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    ABSTRACT: Urokinase plasminogen activator (uPA) and urokinase plasminogen activator receptor (uPAR) play a major role in the infiltrative growth of glioblastoma. Downregulatoion of the uPA and uPAR has been reported to inhibit the growth glioblastoma. Here, we demonstrate that tristetraprolin (TTP) inhibits the growth of U87MG human glioma cells through downregulation of uPA and uPAR. Our results show that expression level of TTP is inversely correlated with those of uPA and uPAR in human glioma cells and tissues. TTP binds to the AU-rich elements within the 3' untranslated regions of uPA and uPAR and overexpression of TTP decreased the expression of uPA and uPAR through enhancing the degradation of their mRNAs. In addition, overexpression of TTP inhibited the growth and invasion of U87MG cells. Our findings implicate that TTP can be used as a promising therapeutic target to treat human glioma.
    Molecules and cells. 12/2014;
  • [Show abstract] [Hide abstract]
    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
  • Source
    [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    ABSTRACT: Destruction of dopaminergic neurons in the substantia nigra pars compacta (SNpc) is a common pathophysiology of Parkinson's disease (PD). Characteristics of PD patients include bradykinesia, muscle rigidity, tremor at rest and disturbances in balance. For about four decades, PD animal models have been produced by toxin-induced or gene-modified techniques. However, in mice, none of the gene-modified models showed all 4 major criteria of PD. Moreover, distinguishing between PD model pigs and normal pigs has not been well established. Therefore, we planned to produce a pig model for PD by chronic subcutaneous administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), neurotoxin. Changes in behavioral patterns of pigs were thoroughly evaluated and a new motor scoring system was established for this porcine model that was based on the Unified Parkinson's Disease Rating Scale (UPDRS) in human PD patients. In summary, this motor scoring system could be helpful to analyze the porcine PD model and to confirm the pathology prior to further examinations, such as positron emission tomography-computed tomography (PET-CT), which is expensive, and invasive immunohistochemistry (IHC) of the brain.
    Experimental neurobiology. 09/2014; 23(3):258-65.
  • Source
    [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although the optimal treatment of frail glioblastoma patients is still controversial, previous randomized trials have excluded such patients. This study aimed to evaluate the feasibility and safety of hypofractionated radiotherapy (RT) with concomitant temozolomide for glioblastoma patients with poor prognostic features. We retrospectively reviewed 33 glioblastoma patients who underwent postoperative hypofractionated chemoradiotherapy. The patient criteria were either ≥70 years or <70 years with one or more risk factors: pre-RT performance status (ECOG score) ≥3, biopsy only, or rapid disease progression immediately after surgery. The median RT dose was 45 Gy (range 30-45) with a fraction size of 3 Gy. The median age was 66.0 years. Eighteen patients (55 %) had poor pre-RT performance status (ECOG ≥3), and 16 patients (48 %) underwent stereotactic biopsy only. The median overall survival (OS) and progression-free survival were 10.6 and 7.5 months, respectively. Poor pre- and post-RT performance status [hazard ratio (HR) 3.12, 95 % confidence interval (CI) 1.21-8.07 and HR 4.51, 95 % CI 1.44-14.12, respectively] and no pseudoprogression (HR 5.43, 95 % CI 1.58-18.61) were associated with poorer OS. While acute neurologic symptoms were reported in 5 patients (15 %), toxicity profiles were acceptable without treatment-related aggravation of performance status. Concurrent chemoradiotherapy with temozolomide, the current standard treatment after surgery for glioblastoma, could be shortened without increasing side effects for patients with poor prognostic features.
    International Journal of Clinical Oncology 04/2014; · 2.17 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The effect of subthalamic deep brain stimulation (STN DBS) on cognition in Parkinson's disease (PD) remains controversial, and it is unclear which factors are related to cognitive decline and dementia after STN DBS, especially over the long term. To this end, we analyzed the cognitive outcome of 103 non-demented patients with PD who were followed-up for at least 12 months after bilateral STN DBS surgery. Preoperatively, the patients were evaluated with the Unified Parkinson's Disease Rating Scale and neuropsychological tests. The rate of global cognitive decline and the incidence of dementia during follow-up for up to 7 years (mean 42.4 ± 24.5 months) were calculated, and preoperative clinical and neuropsychological factors associated with postoperative global cognitive decline or dementia were analyzed. The prevalence of mild cognitive impairment (MCI) and its relation to later cognitive decline or dementia were also evaluated. The annual decline in the mini-mental state examination score was 0.4 ± 1.7 with impaired attention and executive function and a higher levodopa equivalent dose at baseline being the predictors of a faster global cognitive decline after STN DBS. Dementia developed in 13 patients with an incidence rate of 35.7 per 1,000 person-years. Impaired executive function at baseline predicted dementia. At baseline, 63.1 % of the patients had PD-MCI, and these patients were more likely to develop dementia than those without PD-MCI. This study showed that dysfunctions in the frontostriatal circuitry at baseline were associated with a risk of subsequent global cognitive decline and dementia in patients with PD who underwent STN DBS. In addition, preoperative PD-MCI was a risk factor for dementia after STN DBS.
    Journal of Neurology 04/2014; · 3.84 Impact Factor
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pituitary adenoma (PA) is a common benign neuroendocrine tumor; however, the incidence and proportion of hormone-producing PAs in Korean patients remain unknown. Authors analyzed 506 surgically resected and pathologically proven pituitary lesions of the Seoul National University Hospital from 2006 to 2011. The lesions were categorized as: PAs (n = 422, 83.4%), Rathke's cleft cysts (RCCs) (n = 54, 10.6%), inflammatory lesions (n = 8, 1.6%), meningiomas (n = 4), craniopharyngiomas (n = 4), granular cell tumors (n = 1), metastatic renal cell carcinomas (n = 2), germinomas (n = 1), ependymomas (n = 1), and unsatisfactory specimens (n = 9, 1.8%). PAs were slightly more prevalent in women (M: F = 1:1.17) with a mean age of 48.8 yr (9-80 yr). Immunohistochemical analysis revealed that prolactin-producing PAs (16.6%) and growth hormone-producing adenomas (9.2%) were the most common functional PAs. Plurihormonal PAs and nonfunctioning (null cell) adenomas were found in 14.9% and 42.4% of patients with PAs, respectively. The recurrence rate of PAs was 11.1%, but nearly 0% for the remaining benign lesions such as RCCs. 25.4% of patients with PAs were treated by gamma-knife after surgery due to residual tumors or regrowth of residual tumor. In conclusion, the pituitary lesions and the proportions of hormone-producing PAs in Korean patients are similar to those of previous reports except nonfunctioning (null cell) PAs, which are unusually frequent.
    Journal of Korean medical science 03/2014; 29(3):405-10. · 0.84 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cell-based drug delivery systems (DDSs) have been increasingly exploited because cells can be utilized as a continuous drug delivering system to produce therapeutic molecules over a more extended period compared to the simple drug carriers. Although hydrogels have many advantages for this application, their mechanical properties are generally not desirable to structurally protect implanted cells. Here, we present a three-dimensional (3D) hybrid scaffold with a combination of a 3D framework and a hydrogel to enhance the mechanical properties without chemically altering the transport properties of the hydrogel. Based on the 3D Ormocomp scaffold (framework) fabricated by projection-based microstereolithography with defined parameters, we developed a 3D hybrid scaffold by injection of the mixture of cells and the alginate gel into the internal space of the framework. This hybrid scaffold showed the improved mechanical strength and the framework in the scaffold played the role of an adhesion site for the encapsulated cells during the culture period. Additionally, we confirmed its protection of exogenous human cells from acute immune rejection in a mouse model. Eventually, we demonstrated the feasibility of applying this hybrid scaffold to the treatment of Parkinson's disease as a cell-based DDS. Dopamine released from the 3D hybrid scaffolds encapsulating dopamine-secreting cells for 8weeks suggested its clinical applicability. Further study on its long-term efficacy is necessary for the clinical applicability of this 3D hybrid scaffold for the treatment of Parkinson's disease.
    Journal of Controlled Release 12/2013; · 7.63 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    This article is viewable in ResearchGate's enriched format
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    ABSTRACT: Patients with parkin mutations are expected to be good candidates for deep brain stimulation (DBS) because of an excellent levodopa response and frequent occurrence of levodopa-induced dyskinesia. However, there are insufficient data on surgical outcome in patients with parkin mutations. This study aimed to compare the outcome of subthalamic nucleus DBS in patients with early-onset Parkinson's disease with and without parkin mutations. Fourteen patients with early-onset Parkinson's disease who underwent bilateral subthalamic nucleus DBS surgery were screened for parkin mutations and assessed for surgical outcomes at baseline and 2-5years after surgery. Three patients had homozygote/compound heterozygote mutations; two had single heterozygote mutations; and nine had no mutations. Patients with homozygote/compound heterozygote mutations were younger at disease onset and had longer disease duration than patients without a parkin mutation. Postoperatively, there were no significant differences in improvement on the Unified Parkinson's Disease Rating Scale part II, III, and IV, or the reduction of levodopa equivalent daily doses between patients with and without parkin mutations. The therapeutic effect of DBS did not differ between patients with and without parkin mutations.
    Journal of Clinical Neuroscience 09/2013; · 1.32 Impact Factor
  • Sun Ha Paek
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the 1980s when DBS was introduced to treat patients with movement disorders, it has been an effective treatment option for patients with movement disorders such as advanced Parkinson's disease, dystonia, and tremor and is currently being investigated for a variety of psychiatric disorders including obsessive compulsive disorder, depression, substance abuse, anorexia nervosa, obesity, and anxiety disorders. Despite its effectiveness in various neurological and psychiatric diseases, we still do not know the underlying mechanism of how DBS works in sick brains and where the best target in sick brains is to achieve the best clinical improvement. I am sure that the article entitled "An anatomical review of the thalamo-limbic fiber tractography: ultra-high resolution direct visualization of the thalamo-limbic fibers ATR, slMFB, imMFB, and the newly identified septum pellucidum tract", clearly opens the door to a new horizon for a better understanding of the structural and functional connections among brainstem-thalamo-limbic structures, which will be key in solving fundamental questions on understanding how the normal brain works and the dysfunctions of the sick brain as well as provide a reasonable approach to the clinical application of DBS in repairing or remodeling the sick brain in the near future.
    World Neurosurgery 09/2013; · 2.42 Impact Factor
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    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
    This article is viewable in ResearchGate's enriched format
  • Source
    [Show abstract] [Hide abstract]
    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

3k Citations
589.81 Total Impact Points


  • 1997–2014
    • Seoul National University Hospital
      • • Department of Radiation Oncology
      • • Department of Neurosurgery
      • • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2013
    • Konkuk University Medical Center
      • Department of Neurology
      Changnyeong, South Gyeongsang, South Korea
    • Ajou University
      Sŏul, Seoul, South Korea
  • 2010–2013
    • National University of Singapore
      • Department of Electrical & Computer Engineering
      Singapore, Singapore
    • Inje University
      • College of Medicine
      Kimhae, South Gyeongsang, South Korea
  • 2009–2013
    • Seoul National University Bundang Hospital
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
  • 2003–2013
    • Seoul National University
      • • College of Medicine
      • • Department of Neurosurgery
      Seoul, Seoul, South Korea
  • 2010–2012
    • Gachon University
      • • Lee Gil Ya Cancer and Diabetes Institute
      • • Neuroscience Research Institute
      Seoul, Seoul, South Korea
  • 1992–2012
    • Hanyang University
      • • Department of Biomedical Engineering
      • • Division of Materials Science and Engineering (MSE)
      Ansan, Gyeonggi, South Korea
  • 2008–2009
    • Dongguk University
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
    • Inje University Paik Hospital
      Sŏul, Seoul, South Korea
    • Korea Basic Science Institute KBSI
      Sŏul, Seoul, South Korea
    • Seoul Medical Center
      Sŏul, Seoul, South Korea
  • 2006
    • Kyungpook National University
      • School of Medicine
      Daikyū, Daegu, South Korea
    • Kangwon National University Hospital
      Shunsen, Gangwon, South Korea
  • 2005
    • National Cancer Center Korea
      Kōyō, Gyeonggi Province, South Korea
  • 1995
    • Hanseo University
      Kōjō, South Chungcheong, South Korea
    • University of Seoul
      Sŏul, Seoul, South Korea