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Featured researches published by Yun Ig.


Cerebrovascular Diseases | 1999

Recurrence of Bleeding in Patients with Hypertensive Intracerebral Hemorrhage

Hack-Gun Bae; Du-Shin Jeong; Jae-Won Doh; Lee Ks; Yun Ig; B J Byun

To characterize the recurrence of bleeding in patients who had hypertensive intracerebral hemorrhage (HICH), the authors reviewed 989 patients who underwent treatment for HICH between 1989 and 1995. Fifty-three patients (5.4%) had two episodes of HICH within a median interval of 22.9 ± 16.3 months (range 1.5–72 months), and of these 3 (5.7%) had three episodes of HICH. The recurrence of bleeding most commonly occurred within 2 years of the first hemorrhage: in 66% of the 53 patients the second hemorrhage occurred soon after the first (within 1 year in 34%, within 1–2 years in 32.1%). The site of the second hemorrhage was different from the initial site in all patients. Only 1 patient had a third hemorrhage in the same site as the second hemorrhage. The common patterns of recurrence were ‘ganglionic (putamen/caudate nucleus)-thalamic’ in 26.8% and ‘ganglionic-ganglionic’ in 21.4%. The ‘lobar-lobar’ pattern was noted in only 2 patients. The volume of the hematoma was increased at the second hemorrhage. The overall mortality was 28.3%. The risk of recurrent hemorrhage significantly increased in the patients who had antihypertensive therapy of less than 3 months after the initial attack compared to those with further long-term therapy (p < 0.005). Long-term regular control for hypertension is needed to prevent recurrent hemorrhage.


Journal of Korean Neurosurgical Society | 2011

Acute-on-Chronic Subdural Hematoma: Not Uncommon Events

Lee Ks; Jae-Jun Shim; Seok-Mann Yoon; Jae-Won Doh; Yun Ig; Hack-Gun Bae

OBJECTIVE Patients with asymptomatic chronic subdural hematoma (SDH) are prone to fall or slip. Acute trauma on these patients may develop acute subdural bleeding over the chronic SDH. We recently experienced 9 patients with acute-on-chronic SDH. We report the clinical and radiological features of this lesion. METHODS We retrospectively examined the computed tomographic (CT) scans of 107 consecutive patients who diagnosed as chronic SDH from January 2008 to December 2010. All cases of CSDH were diagnosed on CT with or without MRI scan. RESULTS Acute-on-chronic SDH is not rare, being 8% of chronic SDH. The most common cause of trauma was a slip in drunken state. Alcoholism with multiple episodes of trauma was one of the prominent histories. Acute-on-chronic SDH appeared as a hyperdense layer of clot with irregular blurred margin or lumps in liquefied hematoma. Single or two burr holes was usually effective to remove the hematoma. CONCLUSION Repeated trauma may cause acute bleeding over the chronic SDH. It will be helpful to understand the role of repeated trauma as a mechanism of hematoma enlargement.


Journal of Korean Neurosurgical Society | 2010

Spontaneous Intracranial Epidural Hematoma Originating from Dural Metastasis of Hepatocellular Carcinoma

Byoung-Gu Kim; Seok-Mann Yoon; Hack-Gun Bae; Yun Ig

Spontaneous intracranial epidural hematoma (EDH) due to dural metastasis of hepatocellular carcinoma is very rare. A 53-year-old male patient with hepatocellular carcinoma, who was admitted to the department of oncology, was referred to department of neurosurgery because of sudden mental deterioration to semicoma with papillary anisocoria and decerebrate rigidity after transarterial chemoembolization for hepatoma. Brain computed tomography (CT) revealed large amount of acute EDH with severe midline shifting. An emergent craniotomy and evacuation of EDH was performed. Active bleeding from middle cranial fossa floor was identified. There showed osteolytic change on the middle fossa floor with friable mass-like lesion spreading on the overlying dura suggesting metastasis. Pathological examination revealed anaplastic cells with sinusoidal arrangement which probably led to spontaneous hemorrhage and formation of EDH. As a rare cause of spontaneous EDH, dural metastasis from malignancy should be considered.


Journal of Korean Neurosurgical Society | 2010

Morphological Characteristics of the Thalamoperforating Arteries

Sukh Que Park; Hack-Gun Bae; Seok-Mann Yoon; Jai-Joon Shim; Yun Ig; Soon Kwan Choi

OBJECTIVE The aim of this study was to investigate the morphological characteristics of the thalamoperforating arteries that arise from the P1 segment of the posterior cerebral artery. METHODS Thalamoperforating arteries located in the interpeduncular fossa were dissected in 26 formalin-fixed human cadaver brains. We investigated the origin site of thalamoperforating arteries from the P1 segment, number and diameter, and variations in their origin. RESULTS Thalamoperforating arteries arose from the superior, posterior or posterosuperior surfaces of the P1 segment at the mean 1.93 mm (range, 0.41-4.71 mm) distance from the basilar apex and entered the brain through the posterior perforated substance. The average number was 3.6 (range 1-8) and mean diameter was 0.70 mm (range 0.24-1.18 mm). Thalamoperforating arteries could be classified into five different types according to their origin at the P1 segment : Type I (bilateral multiple), 38.5%; Type II (unilateral single, unilateral multiple), 26.9%; Type III (bilateral single), 19.2%; Type IV (unilateral single), 11.5%; Type V (unilateral multiple), 3.8%. In 15.4% of all specimens, thalamoperforating arteries arose from the only one side of P1 segment and were not noted in the other side. In such cases, the branches arising from the one side of P1 segment supplied the opposite side. CONCLUSION Variations in the origin of the thalamoperforating arteries should be keep in mind to perform the surgical clipping, endovascular treatment or operation involving the interpeduncular fossa. In particular, unilateral single branch seems to be very risky and significant for surgical technique or endovascular treatment.


Cerebrovascular Diseases | 2012

Which Treatment Modality Is More Injurious to the Brain in Patients with Subarachnoid Hemorrhage? Degree of Brain Damage Assessed by Serum S100 Protein after Aneurysm Clipping or Coiling

Jae-Hyun Shim; Seok-Mann Yoon; Hack-Gun Bae; Yun Ig; Jai-Joon Shim; Lee Ks; Jae-Won Doh

Background: Serum S100 protein has been known to reflect the severity of brain damage. The purpose of this study was to compare the degree of brain damage based on the serum S100 protein level between aneurysm clipping and coiling groups and to evaluate the prognostic value of S100 protein in patients with subarachnoid hemorrhage (SAH). Methods: Serum S100 protein was measured by Elecsys S100 immunoassay at admission, and at 6 and 24 h, and days 3 and 5 postoperatively for 100 consecutive SAH patients (clipping group: 56, coiling group: 44) and for 74 healthy controls. Hunt-Hess grade (HHG), Fisher grade (FG), the presence of intraventricular (IVH) or intracerebral hemorrhage (ICH), and outcome at discharge were evaluated. The time course of serum S100 was compared between the groups. The prognostic value of S100 protein was evaluated by logistic regression analysis. Results: The median S100 level in SAH patients on admission was significantly higher than in healthy controls (0.081 vs. 0.05 µg/l, p < 0.0001) and it was also higher as HHG and FG increased (p < 0.0001). Logistic regression analysis revealed that only the S100 value at admission was an independent prognostic factor for poor outcomes after adjusting for age, sex, HHG, presence of IVH or ICH, and treatment modality (OR: 100.5, 95% CI: 1.65–6,053.61). The baseline S100 value of 0.168 predicted poor outcomes with a sensitivity of 75% and a specificity of 83%. The time course of the median S100 level peaked at 6 h and then decreased serially in both clipping and coiling groups. However, the degree of S100 elevation was marked in the clipping group, especially at 6 h postoperatively (0.177 vs. 0.116 µg/l, p = 0.022), suggesting more severe brain damage in the clipping group. In the coiling group, the S100 value was significantly higher in patients who showed high signal intensity lesions in diffusion-weighted images, suggesting ischemic brain damage. Furthermore, even in patients who were categorized as good clinical grade at admission and as good outcome at discharge, the median S100 values at 6 and 24 h postoperatively were significantly higher in the clipping group than in the coiling group (p < 0.05). Conclusion: The initial S100 protein value is an independent prognostic factor for poor outcomes in SAH patients. Based on the S100 protein level, aneurysm clipping seems to provoke more brain damage than aneurysm coiling. Endovascular coiling should be considered the first therapeutic option for aneurysmal SAH patients.


Journal of Korean Medical Science | 2004

Transient Paraparesis After Laminectomy in a Patient with Multi-Level Ossification of the Spinal Ligament

Lee Ks; Jae-Jun Shim; Jae-Won Doh; Seok-Mann Yoon; Hack-Gun Bae; Yun Ig

Acute neurologic deterioration is not a rare event in the surgical decompression for thoracic spinal stenosis. We report a case of transient paraparesis after decompressive laminectomy in a 50-yr-old male patient with multi-level thoracic ossification of the ligamentum flavum and cervical ossification of the posterior longitudinal ligament. Decompressive laminectomy from T9 to T11 was performed without gross neurological improvement. Two weeks after the first operation, laminoplasty from C4 to C6 and additional decompressive laminectomies of T3, T4, T6, and T8 were performed. Paraparesis developed 3 hr after the second operation, which recovered spontaneously 5 hr thereafter. CT and MRI were immediately performed, but there were no corresponding lesions. Vascular compromise of the borderlines of the arterial supply by microthrombi might be responsible for the paraparesis.


British Journal of Neurosurgery | 2003

Diagnostic criteria for the clinical syndrome of internal disc disruption: are they reliable?

Kyu-Taeg Lee; Jae-Won Doh; Hack-Gun Bae; Yun Ig

A new disease, named internal disc disruption (IDD), has provoked debate. Some insist that discography is specific for the diagnosis, while others disagree. Without scientific verification, some doctors have performed invasive operations for this uncertain disease. It is necessary to explore the diagnostic criteria and characteristics of IDD. We investigated the background, history, diagnostic methods and criteria of IDD by a review of the literature. The criteria for diagnosis of IDD are diverse. The minimum requirements for the diagnosis were the pattern of pain and the shape on discography. Although the pain pattern is important for the correct diagnosis, it depends on the subjective report of the patient. The diagnosis is up to the patient, and the examiner alone cannot make it. We conclude that IDD is not a real, but a hypothetical disease. Until scientific verification is forthcoming any invasive procedures should be restricted.


Journal of Cerebrovascular and Endovascular Neurosurgery | 2014

Thromboembolic Event Detected by Diffusion Weighted Magnetic Resonance Imaging After Coil Embolization of Cerebral Aneurysms

Dong-Ho Seo; Seok-Mann Yoon; Hye-Ran Park; Jai-Joon Shim; Hack-Gun Bae; Yun Ig

Objective The purpose of this study was to evaluate the occurrence rate of diffusion positive lesions (DPLs), and to assess the peri-procedural risk factors for the occurrence of DPLs in patients who underwent coil embolization of cerebral aneurysms. Materials and Methods A total of 304 saccular aneurysms were embolized during a seven-year period from Jan 2007 to Dec 2013. Of these, postoperative diffusion-weighted images were obtained in 186 procedures. There were 100 ruptured aneurysm and 86 unruptured aneurysms. The coiling procedures were as follows: simple coiling in 96, balloon assisted coiling (BAC) in 39, and stent assisted coiling (SAC) in 51 aneurysms. Clinical, angiographic and procedural factors were analyzed in relation to the occurrence of DPLs. Results Overall, DPLs were observed in 50.5%. In unruptured aneurysms, DPLs occurred in 23.5% of BAC, 41.9% of SAC and 57.7% of simple coiling (p = 0.08). Among ruptured aneurysms, DPLs occurred in 63.6% of BAC, 62.5% of SAC and 54.3% of simple coiling (p = 0.71). DPLs had a tendency to increase in ruptured aneurysms compared with unruptured aneurysms (57% vs. 43%, p = 0.077). Logistic regression analysis revealed that age > 55 years was the only independent risk factor for the occurrence of DPLs. Conclusion DPLs occured more frequently in ruptured aneurysm and at an older age. Although most DPLs are asymptomatic, careful manipulation of cerebral or extracerebral arteries using various endovascular devices is important to reducing the occurrence of DPLs. BAC appeared to reduce occurrence of TE events in patient with unruptured aneurysm.


Journal of Korean Neurosurgical Society | 2008

Open Surgical Evacuation of Spontaneous Putaminal Hematomas: Prognostic Factors and Comparison of Outcomes between Transsylvian and Transcortical Approaches

Dong-Sung Shin; Seok-Mann Yoon; Sung-Ho Kim; Jai-Joon Shim; Hack-Gun Bae; Yun Ig

OBJECTIVE The purpose of this study was to investigate the factors affecting the surgical outcome and to compare the surgical results between transsylvian and transcortical approaches in patients with putaminal hematomas. METHODS Retrospective review of charts and CT scan images was conducted in 45 patients (20 transsylvian and 25 transcortical approaches) who underwent open surgical evacuation of putaminal hematomas. Mean Glasgow coma scale (GCS) score and hematoma volume were 7.5+/-3.2 and 78.1+/-29.3 cc, respectively. The factors affecting the functional mortality were investigated using a multivariate logistic regression analysis. In addition, surgical results between transsylvian and transcortical approaches were compared. RESULTS None of the patients had a good recovery after the surgery. Overall functional survival rate and mortality were 37.7% and 31%, respectively. The only risk factor for functional mortality was GCS motor score after controlling age, history of hypertension, side of hematoma, hematoma amount, midline shift, presence of intraventricular hemorrhage and surgical approach (p=0.005). Even though a transcortical approach was shorter in operative time (4.4 versus 5.1 hour) and showed a higher mortality rate (40% versus 20%) and lower functional survival (45% versus 35%) compared to the transsylvian approach, the differences were not statistically significant between the two groups. CONCLUSION In patients who have large amounts of hematoma and require open surgical evacuation, the only significant risk factor for functional survival is the preoperative GCS score. Cortical incision methods such as transsylvian and transcortical approaches have no influence on the surgical outcome. To decompress the swollen brain rapidly, transcortical approach seems to be more suitable than transsylvian approach.


Journal of Cerebrovascular and Endovascular Neurosurgery | 2015

Iatrogenic Carotid-Cavernous Fistula after Stent Assisted Coil Embolization of Posterior Communicating Artery Aneurysm

Hye-Ran Park; Seok-Mann Yoon; Jai-Joon Shim; Hack-Gun Bae; Yun Ig

Stent assisted coiling (SAC) is a useful technique for the treatment of wide necked complex aneurysm. As the frequency of SAC increases, stent-related complications such as thromboembolism, aneurysm rupture, and vessel rupture have been reported. However, to the best of our knowledge, carotid-cavernous fistula (CCF) after SAC has never been reported. The authors experienced a case of direct CCF after a SAC procedure for treatment of a complex posterior communicating artery (PCoA) aneurysm regrowth, which was treated by clip ligation 12 years before. The patient was managed conservatively and angiograms performed three months after the procedure showed the complete obliteration of the left PcoA aneurysm and the spontaneous disappearance of CCF. Navigation of Solitaire stent lumen with microcatheter can cause unexpected arterial injury, especially when the proximal tip is placed in the curved portion. It seems to be desirable to place the proximal tip of Solitaire stent in the straight portion whenever possible to reduce the risk of inadvertent arterial injury which might be caused by future navigation of stent lumen.

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Lee Ks

Soonchunhyang University

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Bae Hg

Soonchunhyang University Hospital

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Doh Jw

Soonchunhyang University Hospital

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Hack-Gun Bae

Soonchunhyang University

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B J Byun

Soonchunhyang University

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Jae-Won Doh

Soonchunhyang University

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Seok-Mann Yoon

Soonchunhyang University

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I S Lee

Soonchunhyang University

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Jai-Joon Shim

Soonchunhyang University

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Seong-Min Choi

Chonnam National University

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