Chang Ki Hong

Yonsei University Hospital, Seoul, Seoul, South Korea

Are you Chang Ki Hong?

Claim your profile

Publications (13)20.73 Total impact

  • Article: Temporary stenting and retrieval of the self-expandable, intracranial stent in acute middle cerebral artery occlusion
    [show abstract] [hide abstract]
    ABSTRACT: We describe our experience in which a retrievable Enterprise stent was used as a temporary recanalization and embolectomy device in an acute middle cerebral artery (MCA) occlusion after urgent stenting for ipsilateral carotid artery stenosis.
    Neuroradiology 04/2012; 51(8):541-544. · 2.82 Impact Factor
  • Article: Endovascular treatment of iatrogenic intracranial pseudoaneurysm following stent angioplasty.
    [show abstract] [hide abstract]
    ABSTRACT: Intracranial pseudoaneurysm (IPA) is a rare disease entity associated with blunt trauma or penetration injury and less likely surgical or endovascular procedure. Decision of the therapeutic option is difficult and challenging in the treatment of iatrogenic pseudoaneurysm from the middle cerebral artery (MCA) that is necessary to maintain. We report our experience of reconstructive treatment of iatrogenic IPA, which was developed after stenting and balloon angioplasty, in the left MCA with overlapping Enterprise stents.
    Journal of neuroimaging: official journal of the American Society of Neuroimaging 03/2011; 22(2):194-6. · 1.72 Impact Factor
  • Article: Benefits of surgical treatment for unruptured intracranial aneurysms in elderly patients.
    [show abstract] [hide abstract]
    ABSTRACT: Due to longer life spans, patients newly diagnosed with unruptured intracranial aneurysms (UIAs) are increasing in number. This study aimed to evaluate how management of UIAs in patients age 65 years and older affects the clinical outcomes and post-procedural morbidity rates in these patients. We retrospectively reviewed 109 patients harboring 136 aneurysms across 12 years, between 1997 and 2009, at our institute. We obtained the following data from all patients : age, sex, location and size of the aneurysm(s), presence of symptoms, risk factors for stroke, treatment modality, and postoperative 1-year morbidity and mortality. We classified these patients into three groups : Group A (surgical clipping), Group B (coil embolization), and Group C (observation only). Among the 109 patients, 56 (51.4%) underwent clipping treatment, 25 (23%) patients were treated with coiling, and 28 observation only. The overall morbidity and mortality rates were 2.46% and 0%, respectively. The morbidity rate was 1.78% for clipping and 4% for coiling. Factors such as hypertension, diabetes mellitus, hypercholesterolemia, smoking, and family history of stroke were correlated with unfavorable outcomes. Two in the observation group refused follow-up and died of intracranial ruptured aneurysms. The observation group had a 7% mortality rate. Our results show acceptable favorable outcome of treatment-related morbidity comparing with the natural history of unruptured cerebral aneurysm. Surgical clipping did not lead to inferior outcomes in our study, although coil embolization is generally more popular for treating elderly patients. In the treatment of patients more than 65 years old, age is not the limiting factor.
    Journal of Korean Neurosurgical Society 01/2011; 49(1):20-5. · 0.60 Impact Factor
  • Article: Anti-platelet drug resistance in the prediction of thromboembolic complications after neurointervention.
    [show abstract] [hide abstract]
    ABSTRACT: The aim of this study was to analyze the correlation between thromboembolic complications and antiplatelet drugs before and after neurointervention. Blood samples and radiographic data of patients who received a neurointervention (coil embolization, stent placement or both) were collected prospectively. Rapid platelet function assay-aspirin (RPFA-ASA) was used to calculate aspirin resistance in aspirin reaction units (ARU). For clopidogrel resistance, a P2Y12 assay was used to analyze the percentage of platelet inhibition. ARU > 550 and platelet inhibition < 40% were defined as aspirin and clopidogrel resistance, respectively. Both aspirin and clopidogrel oral pills were administered in fifty-three patients before and after neurointerventional procedures. The mean resistance values of all patients were 484 ARU and < 39%. Ten (17.0%) of 53 patients showed resistance to aspirin with an average of 597 ARU, and 33 (62.3%) of 53 patients showed resistance to clopidogrel with an average of < 26%. Ten patients demonstrated resistance to both drugs, 5 of which suffered a thromboembolic complication after neurointervention (mean values : 640 ARU and platelet inhibition < 23%). Diabetic patients and patients with hypercholesterolemia displayed mean aspirin resistances of 513.7 and 501.8 ARU, and mean clopidogrel resistances of < 33.8% and < 40.7%, respectively. Identifying individuals with poor platelet inhibition using standard regimens is of great clinical importance and may help prevent cerebral ischemic events in the future. Neurointerventional research should focus on ideal doses, timing, choices, safety, and reliable measurements of antiplatelet drug therapy, as well as confirming the clinical relevance of aggregometry in cerebrovascular patients.
    Journal of Korean Neurosurgical Society 10/2010; 48(4):319-24. · 0.60 Impact Factor
  • Article: Characteristics and management of residual or slowly recurred intracranial aneurysms.
    [show abstract] [hide abstract]
    ABSTRACT: Residual aneurysm from incomplete clipping or slowly recurrent aneurysm is associated with high risk of subarachnoid hemorrhage. We describe complete treatment of the lesions by surgical clipping or endovascular treatment. We analyzed 11 patients of residual or recurrent aneurysms who had undergone surgical clipping from 1998 to 2009. Among them, 5 cases were initially clipped at our hospital. The others were referred from other hospitals after clipping. The radiologic and medical records were retrospectively analyzed. All patients presented with subarachnoid hemorrhage at first time, and the most frequent location of the ruptured residual or recurrent aneurysm was in the anterior communicating artery to posterior-superior direction. Distal anterior cerebral artery, posterior communicating artery, and middle cerebral artery was followed. Repositioning of clipping in eleven cases, and one endovascular treatment were performed. No residual aneurysm was found in postoperative angiography, and no complication was noted in related to the operations. These results indicate the importance of postoperative or follow up angiography and that reoperation of residual or slowly recurrent aneurysm should be tried if such lesions being found. Precise evaluation and appropriate planning including endovascular treatment should be performed for complete obliteration of the residual or recurrent aneurysm.
    Journal of Korean Neurosurgical Society 10/2010; 48(4):330-4. · 0.60 Impact Factor
  • Article: Treatment of unruptured intracranial aneurysms in South Korea in 2006 : a nationwide multicenter survey from the korean society of cerebrovascular surgery.
    [show abstract] [hide abstract]
    ABSTRACT: There have been no clinical studies regarding the epidemiology and treatment outcome for unruptured intracranial aneurysm (UIA) in South Korea yet. Thus, The Korean Society of Cerebrovascular Surgery (KSCVS) decided to evaluate the clinical and epidemiological characteristics, and outcome of the treatment of UIA in 2006, using the nationwide multicenter survey in South Korea. A total of 1,696 cases were enrolled retrospectively over one year at 48 hospitals. The following data were obtained from all patients : age, sex, presence of symptoms, location and size of the aneurysm, treatment modality, presence of risk factors for stroke, and the postoperative 30-day morbidity and mortality. The demographic data showed female predominance and peak age of seventh and sixth decades. Supraclinoid internal carotid artery was the most common site of aneurysms with a mean size of 5.6 mm. Eight-hundred-forty-six patients (49.9%) were treated with clipping, 824 (48.6%) with coiling, and 26 with combined method. The choice of the treatment modalities was related to hospital (p = 0.000), age (p = 0.000), presence of symptom (p = 0.003), and location of aneurysm (p = 0.000). The overall 30-day morbidity and mortality were 7.4% and 0.3%, respectively. The 30-day mortality was 0.4% for clipping and 0.2% for coiling, and morbidity was 8.4% for clipping and 6.3% for coiling. Age (p = 0.010), presence of symptoms (p = 0.034), size (p = 0.000) of aneurysm, and diabetes mellitus (p = 0.000) were significant prognostic factors, while treatment modality was not. This first nation-wide multicenter survey on UIAs demonstrates the epidemiological and clinical characteristics, outcome and the prognostic factors of the treatment of UIAs in South Korea. The 30-day postoperative outcome for UIAs seems to be reasonable morbidity and mortality in South Korea.
    Journal of Korean Neurosurgical Society 02/2010; 47(2):112-8. · 0.60 Impact Factor
  • Article: Ectopic ventricular recurrence of an epidermoid cyst in the middle fossa.
    [show abstract] [hide abstract]
    ABSTRACT: We present the first case of ectopic ventricular recurrence of an epidermoid cyst in the middle fossa with confirming histological characteristics. A 51-year-old woman presented with an epidermoid cyst in the middle fossa and underwent complete resection. On the 6-month surgical follow-up MRI, a nodular lesion was detected in the frontal horn of the left lateral ventricle without evidence of recurrence at the primary site. The patient underwent transcortial tumor resection. Results of histological studies confirmed that the lesion was an epidermoid cyst similar to the primary lesion. This is a case report of the cerebrospinal fluid spread of an epidermoid cyst, which strengthens the case for special care at the time of surgery to prevent spread of the lesion.
    Journal of Clinical Neuroscience 06/2008; 15(5):578-80. · 1.25 Impact Factor
  • Article: Leo stent-assisted coil embolization of a giant middle cerebral artery aneurysm.
    [show abstract] [hide abstract]
    ABSTRACT: We report a case of a 70-year-old man harboring a wide-necked thrombosed giant aneurysm of the left middle cerebral artery (MCA) on the M1 segment. The patient presented with generalized tonic-clonic seizures. A computerized tomography scan showed a calcified aneurysmal wall with perianeurysmal swelling. The aneurysm was successfully embolized using closed-cell nitinol stent-assisted coiling (Leo, BALT Co., Montmorency, France).
    Journal of neuroimaging: official journal of the American Society of Neuroimaging 01/2008; 18(3):332-5. · 1.72 Impact Factor
  • Article: Structural and functional insights into intramolecular fructosyl transfer by inulin fructotransferase.
    [show abstract] [hide abstract]
    ABSTRACT: Inulin fructotransferase (IFTase), a member of glycoside hydrolase family 91, catalyzes depolymerization of beta-2,1-fructans inulin by successively removing the terminal difructosaccharide units as cyclic anhydrides via intramolecular fructosyl transfer. The crystal structures of IFTase and its substrate-bound complex reveal that IFTase is a trimeric enzyme, and each monomer folds into a right-handed parallel beta-helix. Despite variation in the number and conformation of its beta-strands, the IFTase beta-helix has a structure that is largely reminiscent of other beta-helix structures but is unprecedented in that trimerization is a prerequisite for catalytic activity, and the active site is located at the monomer-monomer interface. Results from crystallographic studies and site-directed mutagenesis provide a structural basis for the exolytic-type activity of IFTase and a functional resemblance to inverting-type glycosyltransferases.
    Journal of Biological Chemistry 04/2007; 282(11):8414-23. · 4.77 Impact Factor
  • Article: Therapeutic endovascular treatments for traumatic vertebral artery injuries.
    [show abstract] [hide abstract]
    ABSTRACT: Traumatic vertebral artery injuries pose difficulty in early diagnosis and management because of concomitant neurologic dysfunction and limitations in direct surgical access. The purpose of this report is to review endovascular therapy in patients with traumatic vertebral artery injuries for preservation of the parent artery, and to determine the safety and efficacy of such endovascular therapy. Six patients with traumatic vertebral artery lesions were treated using therapeutic endovascular methods. Endovascular therapy was accomplished by stent insertion or coil embolization or both. Except one patient who underwent coil embolization of a transected vertebral artery, all dissections and pseudoaneurysms were successfully treated by stent placement or stent-assisted coiling with preservation of parent arteries. No additional surgical procedures for vascular lesions were required. There were no delayed neurologic or vascular complications and no lesions recurred during the follow-up period (mean, 36.7 months). The author's experience demonstrates that endovascular therapy using stents and coils is both feasible and safe in the treatment of traumatic vertebral artery injuries. Endovascular therapy selectively eliminated the vascular abnormality while maintaining the normal patency of the cerebral arteries. Long-term follow-up review of these repairs will be necessary to provide a full evaluation of the safety and efficacy of these devices.
    The Journal of trauma 04/2007; 62(4):886-91. · 2.48 Impact Factor
  • Article: Cloning, expression, and characterization of Bacillus sp. snu-7 inulin fructotransferase.
    [show abstract] [hide abstract]
    ABSTRACT: A gene encoding inulin fructotransferase (di-D-fructofuranose 1,2': 2,3' dianhydride [DFA III]-producing IFTase, EC 4.2.2.18) from Bacillus sp. snu-7 was cloned. This gene was composed of a single, 1,353-bp open reading frame encoding a protein composed of a 40-amino acid signal peptide and a 410-amino acid mature protein. The deduced amino acid sequence was 98% identical to Arthrobacter globiformis C11-1 IFTase (DFA III-producing). The enzyme was successfully expressed in E. coli as a functionally active, His-tagged protein, and it was purified in a single step using immobilized metal affinity chromatography. The purified enzyme showed much higher specific activity (1,276units/mg protein) than other DFA III-producing IFTases. The recombinant and native enzymes were optimally active in very similar pH and temperature conditions. With a 103-min half-life at 60 degrees C, the recombinant enzyme was as stable as the native enzyme. Acidic residues and cysteines potentially involved in the catalytic mechanism are proposed based on an alignment with other IFTases and a DFA IIIase.
    Journal of Microbiology and Biotechnology 02/2007; 17(1):37-43. · 1.38 Impact Factor
  • Article: Interrelationships among pain, disability, and psychological factors in young Korean conscripts with lumbar disc herniation.
    [show abstract] [hide abstract]
    ABSTRACT: The aim of this study was to compare the psychological factors between young Korean conscripts with lumbar disc herniation (LDH) and healthy controls and to evaluate the interrelationships among pain, disability, and psychological factors in LDH conscripts. The subjects consisted of 56 young conscripts with LDH and 76 controls. All subjects completed Beck's Depression Inventory and Spielberger's State-Trait Anxiety Inventory. To evaluate pain intensity and functional disability, the Visual Analogue Scale and the Modified Oswestry Low Back Pain Disability Questionnaire were used. LDH conscripts had more depression and anxiety than the controls. The functional disability of the LDH conscripts was significantly related to the four variables: pain intensity, depression, state anxiety, and trait anxiety. Pain intensity and state anxiety significantly contributed to the functional disability in the LDH conscripts. This study suggests that LDH conscripts have some psychological problems, such as depression and anxiety, in comparison to healthy controls. Furthermore, the pain intensity and state anxiety predict the functional disability in LDH conscripts.
    Military medicine 12/2006; 171(11):1113-6. · 0.92 Impact Factor
  • Article: Ruptured distal anterior choroidal artery aneurysm.
    [show abstract] [hide abstract]
    ABSTRACT: Ruptured aneurysms of the distal anterior choroidal artery (AchA) are extremely rare and management is dictated by clinical presentation. This report describes a rare patient with a distal AchA aneurysm and subarachnoid and intraventricular haemorrhage. A 60-year-old woman presented with a sudden onset of severe headache and vomiting. No aneurysms could be found on initial angiograms. A repeat angiogram performed 10 days after admission demonstrated an aneurysm in a branch of the cisternal segment of the left AchA without a definite neck. Surrounding vessels showed multifocal stricture and dilatation. Microsurgical clipping was not performed because the patient died suddenly due to pulmonary failure. The aetiology of the aneurysm in this case and surgical strategy are discussed.
    Journal of Clinical Neuroscience 11/2006; 13(8):872-5. · 1.25 Impact Factor