Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Hwang Sn is active.

Publication


Featured researches published by Hwang Sn.


Journal of Korean Neurosurgical Society | 2009

Detection of traumatic cerebral microbleeds by susceptibility-weighted image of MRI.

Jong-Hwa Park; Seung Won Park; Suk-Hyung Kang; Taek-Kyun Nam; Min Bk; Hwang Sn

OBJECTIVE Susceptibility-weighted image (SWI) is a sensitive magnetic resonance image (MRI) technique to detect cerebral microbleeds (MBLs), which would not be detected by conventional MRI. We performed SWI to detect MBLs and investigated its usefulness in the evaluation of mild traumatic brain injury (MTBI) patients. METHODS From December 2006 to June 2007, twenty-one MTBI patients without any parenchymal hemorrhage on conventional MRI were selected. Forty-two patients without trauma were selected for control group. According to the presence of MBLs, we divided the MTBI group into MBLs positive [SWI (+)] and negative [SWI (-)] group. Regional distribution of MBLs and clinical factors were compared between groups. RESULTS Fifty-one MBLs appeared in 16 patients of SWI (+) group and 16 MBLs in 10 patients of control group [control (+)], respectively. In SWI (+) group, MBLs were located more frequently in white matters than in deep nucleus different from the control (+) group (p < 0.05). Nine patients (56.3%) of SWI (+) group had various neurological deficits (disorientation in 4, visual field defect in 2, hearing difficulty in 2 and Parkinson syndrome in 1). Initial Glasgow Coma Scale (GCS)/mean Glasgow Outcome Scale (GOS) were 13.9 +/- 1.5 / 4.7 +/- 0.8 and 15.0 +/- 0.0 / 5.0 +/- 0.0 in SWI (+) and SWI (-) groups, respectively (p < 0.05). CONCLUSION Traumatic cerebral MBLs showed characteristic regional distribution, and seemed to have an importance on the initial neurological status and the prognosis. SWI is useful for detection of traumatic cerebral MBLs, and can provide etiologic evidences for some post-traumatic neurologic deficits which were unexplainable with conventional MRI.


Neurosurgery | 2005

History of Korean stereotactic and functional neurosurgery.

Hwang Sn

ALTHOUGH FUNCTIONAL SURGERY for movement disorders did not begin in Korea until after the introduction of the stereotactic apparatus in 1958, some surgeons had already begun operating on epileptic patients, psychiatric patients, and patients with pain disorders even before the Korean War broke out in 1950. The Korean War itself was a good opportunity for the army surgeons to learn Western neurosurgery, and many operations for pain were performed during this period. Stereotactic thalamotomy and pallidotomy for parkinsonian tremor began in the late 1950s, but it was not until the 1970s that Sang-sup Chung and Chang-rak Choi devoted themselves fully to this field and actively performed these functional operations. They later established the Korean Functional and Stereotactic Society in 1990. Following the lead of these pioneers, many young neurosurgeons began to enter the field in the 1980s to become full-time functional surgeons. Currently, the society has approximately 150 registered members interested in movement disorders, pain, epilepsy, and radiosurgery and working full-time or part-time in this field.


Journal of Korean Neurosurgical Society | 2010

Capillary Hemangioma of the Thoracic Spinal Cord

Sung-Kyun Chung; Taek-Kyun Nam; Seung Won Park; Hwang Sn

Capillary hemangiomas are common soft tissue tumors on the skin or mucosa of the head and neck in the early childhood, but very rare in the neuraxis. A 47-year-old man presented with one month history of back pain on the lower thoracic area, radiating pain to both legs, and hypesthesia below T7 dermatome. Thoracic spine MRI showed 1×1.3×1.5 cm, well-defined intradural mass at T6-7 disc space level, which showed isointensity to spinal cord on T1, heterogeneous isointensity on T2-weighted images, and homogeneous strong enhancement. The patient underwent T6-7 total laminotomy, complete tumor removal and laminoplasty. Histologically, the mass showed a capsulated nodular lesion composed of capillary-sized vascular channels, which were tightly packed into nodules separated by fibrous septa. These features were consistent with capillary hemangioma.


Brain Research | 2000

The effects of N-methyl-N-nitrosourea and azoxymethane on focal cerebral infarction and the expression of p53, p21 proteins.

Seung Won Park; Young-Baeg Kim; Hwang Sn; Duck-Young Choi; Jung-Taik Kwon; Min Bk; Suk Js

If the activity of pro-apoptotic genes can be down-regulated by certain chemicals, cells may be protected from apoptosis. To test this hypothesis in a cerebral infarction model, we used N-methyl-N-nitrosourea (MNU) and azoxymethane (AOM), which were approved gene-modulating chemicals. A focal cerebral infarction was created by coagulation of the right middle cerebral artery and ipsilateral common carotid artery (CCA) and simultaneous transient occlusion of the contralateral CCA for 30 min in 25 adult Sprague-Dawley rats that were sacrificed 24 h later. In one group (n=7), MNU (5 mg/kg) was injected intravenously 30 min before initiation of ischemia. In another group (n=7), AOM (15 mg/kg) was administered intraperitoneally before 24 h of ischemia. The infarction volumes were checked and the brains were stained for p53 and p21 proteins. The width in micrometers of the peri-infarct area containing p53 or p21 protein-positive cells, and the number of p53 or p21 protein-positive cells (cells/HPF) were measured at an adjacent peri-infarct area. The AOM-treated group showed a significantly reduced infarction volume (by 42.5%, p<0.001), a significantly greater number of p53 positive cells (by 12.0%, p<0. 05), and a significantly wider p53 protein-positive area (by 15.6%, p<0.01) than the untreated group. AOM did not show any influence on the expression pattern of the p21 protein. MNU had no effect in the expression of p53 or p21 proteins. As a result, we concluded that AOM revealed a protective effect in ischemia by suppressing the pro-apoptotic activity of the p53 gene. Safer chemicals that can modulate apoptotic genes, if any, will provide a new therapeutic modality for cerebral infarction.


Journal of Korean Neurosurgical Society | 2008

The Effect of Barbiturate Coma Therapy for the Patients with Severe Intracranial Hypertension: A 10-Year Experience

Youngil Kim; Seung Won Park; Taek-Kyun Nam; Yong-Sook Park; Min Bk; Hwang Sn

OBJECTIVE Barbiturate coma therapy (BCT) has been known to be an useful method to control increased intracranial pressure (IICP) refractory to medical and surgical treatments. We have used BCT for patients with severe IICP during the past 10 years, and analyzed our results with review of literatures. METHODS We analyzed 92 semicomatose or comatose patients with Glasgow coma scale (GCS) of 7 or less with severe IICP due to cerebral edema secondary to parenchymal damages irrespective of their causes. Forty patients who had received BCT with ICP monitoring from January 1997 to December 2006 were included in BCT group, and fifty-two patients who had been managed without BCT from January 1991 to December 1995 were divided into control group. We compared outcomes with Glasgow outcome scale (GOS) and survival rate between the two groups. RESULTS Good outcome (GOS=4 and 5) rates at 3-month after insult were 27.5% and 5.8% in BCT and control group, respectively (p<0.01). One-year survival rates were 35.9% and 12.5% in BCT and control group, respectively (p<0.01). In BCT group, the mean age of good outcome patients (37.1 +/- 14.9) was significantly lower than that of poor outcome patients (48.1 +/- 13.5) (p<0.05). CONCLUSION With our 10-year experience, we suggest that BCT is an effective treatment method for severe IICP patients for better survival and GOS, especially for younger patients.


Korean Journal of Neurotrauma | 2015

Comparison of the Outcomes and Recurrence with Three Surgical Techniques for Chronic Subdural Hematoma: Single, Double Burr Hole, and Double Burr Hole Drainage with Irrigation.

Kyoung-Min Jang; Jeong-Taik Kwon; Hwang Sn; Yong-Sook Park; Taek-Kyun Nam

Objective Chronic subdural hematoma (CSDH), a disease commonly encountered by neurosurgeons, is treated by burr hole drainage (BHD). However, the optimal surgical technique among the three types of BHD has not been determined. Methods We conducted a retrospective study on BHD performed on 93 patients who were diagnosed with CSDH. The subjects were divided into three groups based on the surgical technique performed: single BHD without irrigation (Group A, n=31), double BHD without irrigation (Group B, n=32), and double BHD with irrigation (Group C, n=30). The clinical factors, radiological factors and recurrences were compared between the three groups. Moreover, independent factors affecting the recurrence were analyzed. Results The change in hematoma thickness was 29.77±7.94%, 49.73±12.87%, and 75.29±4.32% for Group A, B, and C, respectively, while the change in midline shift was 40.81±15.47%, 51.78±10.94%, and 56.16±16.16%, respectively. Thus, Group C showed the most effective for resolution of hematoma and midline shift (p<0.05). Group A, B, and C had 12 cases (38.7%), 8 cases (25.0%), and 3 cases (10.0%) of recurrences, respectively. Group C had a statistically significantly fewer recurrence rate than Group A (p<0.05). Double burr hole, irrigation, and coagulopathy were each identified as independent factors that reduce recurrence (p<0.05). Conclusion Among the three techniques, the double BHD with saline irrigation resulted in the fewest recurrences. It is probably the most effective technique for preventing the recurrence of CSDH.


Journal of Neurosurgery | 2011

Cerebrospinal fluid pathways from cisterns to ventricles in N-butyl cyanoacrylate–induced hydrocephalic rats

Jong-Hyuk Park; Yong-Sook Park; Suk Js; Seung Won Park; Hwang Sn; Taek-Kyun Nam; Young-Baeg Kim; Won-Bok Lee

OBJECT Cerebrospinal fluid typically enters the subarachnoid space from the ventricles via the fourth ventricular foramina. However, there is clinical evidence that CSF also flows in the opposite direction. Ventricular reflux of CSF from a cistern is a well-known phenomenon in radioisotope studies in patients with normal-pressure hydrocephalus. Additionally, the presence of ventricular blood in acute subarachnoid hemorrhage is frequently observed. The goal of this investigation was to examine the potential CSF pathways from cisterns to ventricles. The authors examined pathways in rat models in which they occluded the fourth ventricular outlets and injected a tracer into the subarachnoid space. METHODS The model for acute obstructive hydrocephalus was induced using N-butyl cyanoacrylate (NBCA) in 10 Sprague-Dawley rats. After 3 days, cationized ferritin was infused into the lumbar subarachnoid space to highlight retrograde CSF flow pathways. The animals were sacrificed at 48 hours, and the brains were prepared. The CSF flow pathway was traced by staining the ferritin with ferrocyanide. RESULTS Ferritin was observed in the third ventricle in 7 of 8 rats with hydrocephalus and in the temporal horn of the lateral ventricles in 4 of 8 rats with hydrocephalus. There was no definite staining in the aqueduct, which suggests that the ventricular reflux originated from routes other than through the fourth ventricular outlets. CONCLUSIONS The interfaces between the quadrigeminal cistern and third ventricle and those between the ambient cistern and lateral ventricle appear to be potential sites of CSF reflux from cisterns to ventricles in obstructive hydrocephalus.


Journal of Korean Neurosurgical Society | 2009

Inflammatory Pseudotumor in the Lateral Ventricle with Repeated Bleeding-Case Report-

Jong-Hwa Park; Taek-Kyun Nam; Hwang Sn; Seung Won Park

Inflammatory pseudotumor is an uncommon lesion with unknown etiology characterized by sclerosing inflammation which clinically and radiographically mimics a neoplastic lesion. A 47-year-old man presented with sudden headache and dysarthria. Brain CT scan revealed a 2.6x2.2 cm sized, round, and hyperdense mass in the anterolateral wall of the left lateral ventricular trigone. On MR imaging studies, the mass showed low signal intensity in the wall of the trigone on T2-weighted image, central mixed (iso- and high-) signal intensity with peripheral low-signal intensity on T1-weighted image. Subtle staining of left choroid plexus with irregular shaped distal branch of anterior choroidal artery was found on the cerebral angiography. These findings suggested a small tumorous lesion originated from the left choroid plexus. During the hospital days, the mass manifested as repeated hemorrhages. The mass was successfully removed via left occipital transcortical approach. The histopathological report of the specimen was hemorrhage and fibrosis, with dense lymphoplasma cell infiltration, suggestive of an inflammatory pseudotumor.


Brain Tumor Research and Treatment | 2013

Primary malignant lymphoma of the cranial vault with extra- and intracranial extension.

Myeong-Jin Ko; Hwang Sn; Yong-Sook Park; Teak Kyun Nam

Bone involvement is a common finding in many types of lymphomas, particularly in advanced stages. However, cranial vault affliction has been regarded as an exceedingly rare presentation. Here, we report the case of a patient with cranial vault lymphoma who presented with a scalp mass. An 81-year-old woman presented with a gradually growing and non-painful frontal scalp mass that she noticed one month before admission. It was a flatly elevated, round mass measuring about 6×4×4 cm. Computed tomography and magnetic resonance imaging of the brain revealed a contrast-enhancing intracranial extradural mass at the counter-location of the scalp mass. The superior sagittal sinus was involved at the tumor site. Cerebral angiography showed that the tumor feeding vessels originated from the bilateral external carotid arteries. An operation was performed and the tumors were removed together with the involved bone. The pathologic diagnosis was malignant diffuse large B-cell type lymphoma. The patient was transferred to the Hemato-Oncology department for chemotherapy. Primary lymphoma of the cranial vault with scalp mass is very rare but it should be considered in the differential diagnosis of scalp masses. Although the results of reported cases are variable, the combination of surgery, radiation, and chemotherapy appears to offer favorable outcomes.


Journal of Korean Neurosurgical Society | 2010

A Case of Temporal Intracerebral Hemorrhage That Presented with Sudden Bilateral Hearing Loss as the Initial Symptom

Seog-Kyun Mun; Young-Ho Hong; Suk-Hyung Kang; Hwang Sn

A 57-year-old man presented to the outpatient department with sudden bilateral hearing loss. The otological examination suggested bilateral severe sensorineural hearing loss. After several hours, the patient complained of a headache and became drowsy. The brain computed tomography showed a 3 × 4 cm intracerebral hemorrhage (ICH) of the left temporal lobe. Surgery was performed and 34 days after the procedure the patient was discharged from the hospital with severe bilateral sensorineural hearing loss (SNHL). Temporal lobe ICH should be considered in the differential diagnosis of patients with sudden bilateral hearing loss, regardless of the other neurological symptoms.

Collaboration


Dive into the Hwang Sn's collaboration.

Top Co-Authors

Avatar

Min Bk

Chung-Ang University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Suk Js

Chung-Ang University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kwan Park

Samsung Medical Center

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge