Won-Sang Cho

Kangwon National University, Shunsen, Gangwon, South Korea

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Publications (19)34.42 Total impact

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    ABSTRACT: The surgical outcomes of adult moyamoya disease are rarely reported. We aimed to evaluate the long-term outcomes of combined revascularization surgery in patients with adult moyamoya disease.
    09/2014;
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    ABSTRACT: Stent-assisted embolization is sometimes limited in wide-necked aneurysms involving the acute-angled origins of tortuous branching arteries, and occasionally, Y-shaped stenting is required to remedy the sweeping effects of a broad aneurysmal neck on arterial branches. Described herein is a modified stent-assisted coil embolization technique entailing strategic placement of far proximal stent ("distal stenting") as an alternate approach in such scenarios.
    Neuroradiology 07/2014; · 2.70 Impact Factor
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    ABSTRACT: Superior cerebellar artery (SCA) aneurysms have distinctive morphologic configurations and vascular origins. Herein, we have analyzed the angioarchitectural characteristics of SCA aneurysms and outcomes achieved through endovascular treatment. Data accruing prospectively from January, 2002 to September, 2013 yielded 53 SCA aneurysms in 53 patients. Each lesion was classified as either basilar artery (BA), BA-SCA, or SCA type, according to the nature of incorporated vasculature. Clinical and morphologic outcomes were assessed, with emphasis on technical aspects of treatment. Angles formed by SCA and posterior cerebral artery were obtuse (124.8 ± 29.1°) on sides ipsilateral to aneurysms, differing significantly from contralateral counterparts (44.8 ± 22.0°) (p < 0.001). The most common type of aneurysm was BA-SCA (54.7 %), followed by SCA (28.3 %) and BA (17.0 %), and BA type aneurysms were the largest in size. Steam-shaped S-configured microcatheters (n = 19, 67.9 %) facilitated aneurysm selection for approach via contralateral vertebral artery (n = 28), whereas pre-shaped 45/90/J microcatheters (n = 21, 84.0 %) primarily were used for ipsilateral vertebral artery approach (n = 25). Single-microcatheter technique (52.8 %) was most often applied, followed by double-microcatheter (34.0 %), stent-assisted (9.4 %), and microcatheter-protection techniques (3.8 %). Aneurysmal occlusion was satisfactorily achieved in 45 lesions (82.1 %), with no procedure-related morbidity and mortality. In follow-up monitoring of 46 patients for a mean period of 25.8 ± 24.4 months, only a single instance of major recanalization (2.2 %) occurred. Coil embolization of SCA aneurysms is a safe and effective treatment modality, enabling individualized procedural strategies to accommodate distinctive angio-anatomic configurations.
    Neuroradiology 05/2014; · 2.70 Impact Factor
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    ABSTRACT: The novel Low-profile Visualized Intraluminal Support (LVIS™, LVIS and LVIS Jr.) device was recently introduced for stent-supported coil embolization of intracranial aneurysms. Periprocedural and midterm follow-up results for its use in stent-supported coil embolization of unruptured aneurysms are presented herein. In this prospective multicenter study, clinical and radiologic outcomes were analyzed for 55 patients with saccular aneurysms undergoing LVIS-assisted coil embolization between October 2012 and February 2013. Magnetic resonance angiography or digital subtraction angiography was performed to evaluate midterm follow-up results. The standard LVIS device, deployed in 27 patients, was more often used in internal carotid artery (ICA) aneurysms (n = 19), whereas the LVIS Jr. (a lower profile stent, n = 28) was generally reserved for anterior communicating artery (n = 14) and middle cerebral artery (n = 8) aneurysms. With LVIS-assisted coil embolization, successful occlusion was achieved in 45 aneurysms (81.8 %). Although no instances of navigation failure or stent malposition occurred, segmentally incomplete stent expansion was seen in five patients where the higher profile LVIS was applied to ICA including carotid siphon. Procedural morbidity was low (2/55, 3.6 %), limited to symptomatic thromboembolism. In the imaging of lesions (54/55, 98.2 %) at 6-month follow-up, only a single instances of major recanalization (1.9 %) occurred. Follow-up angiography of 30 aneurysms (54.5 %) demonstrated in-stent stenosis in 26 (86.7 %), with no instances of stent migration. Only one patient suffered late delayed infarction (modified Rankin Scale 1). The LVIS device performed acceptably in stent-assisted coil embolization of non-ruptured aneurysms due to easy navigation and precise placement, although segmentally incomplete stent expansion and delayed in-stent stenosis were issues.
    Neuroradiology 04/2014; · 2.70 Impact Factor
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    ABSTRACT: The purpose of this study was to assess the risk factors of prospective symptomatic haemorrhage in a large series of adult patients with cerebral cavernous malformation (CM). Three hundred twenty-six patients >18 years of age with 410 CMs were evaluated retrospectively. Symptomatic haemorrhage was defined as new clinical symptoms with radiographic features of haemorrhage. Clinical data and the characteristics of CM were analysed. MR appearance was divided into three groups according to Zabramski's classification. The overall haemorrhage rate of CM was 4.46% per lesion-year. The overall annual haemorrhage rate according to MR appearance was as follows: type I, 9.47%; type II, 4.74%; and type III, 1.43%. A multivariate analysis revealed that prior symptomatic haemorrhage (p<0.001) and MR appearance (p<0.001) were statistically significant. After multiple comparisons, type I (p<0.001) and type II (p=0.016) showed higher haemorrhage risk than type III. However, no significant difference in haemorrhage rate was observed between type I and type II (p=0.105). Other variables including female gender, age, location, multiplicity, hypertension, size and associated venous angioma were not significant. The haemorrhage rates based on risk factors were estimated at 3 years as follows: 33.77% in patients with prior haemorrhage versus 7.54% in patients without prior haemorrhage (p<0.001); type I, 27.62% vs type II, 15.44% vs type III, 5.38% (p<0.001). Prior symptomatic haemorrhage and MR appearance could be related to prospective symptomatic CM haemorrhage in adults. A prospective multicentre observational study is necessary to confirm our results.
    Journal of neurology, neurosurgery, and psychiatry 03/2014; · 4.87 Impact Factor
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    ABSTRACT: Ehlers-Danlos syndrome (EDS) is a rare inherited connective disease. Among several subgroups, type IV EDS is frequently associated with spontaneous catastrophic bleeding from a vascular fragility. We report on a case of carotid-cavernous fistula (CCF) in a patient with type IV EDS. A 46-year-old female presented with an ophthalmoplegia and chemosis in the right eye. Subsequently, seizure and cerebral infarction with micro-bleeds occurred. CCF was completely occluded with transvenous coil embolization without complications. Thereafter, the patient was completely recovered. Transvenous coil embolization can be a good treatment of choice for spontaneous CCF with type IV EDS. However, every caution should be kept during invasive procedure.
    Journal of Korean Neurosurgical Society 02/2014; 55(2):92-5. · 0.56 Impact Factor
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    ABSTRACT: The elevation of cellular retinoic acid-binding protein-I (CRABP-I) has been suggested as a candidate in the pathogenesis of paediatric moyamoya disease (MMD). However, few studies have addressed CRABP-I in adult onset MMD. The aim of this study was to examine the expression of CRABP-I in the cerebrospinal fluid (CSF) of adult onset MMD, and to evaluate its association with clinical presentation and postoperative haemodynamic change. This study examined the CSF from 103 patients: bilateral MMD, n=58 (56.3%); unilateral MMD, n=19 (18.4%); atherosclerotic cerebrovascular disease (ACVD), n=21 (20.4%); and control group, n=5 (4.9%). The intensity of CRABP-I was confirmed by western blotting and expressed as the median (25th-75th percentile). The differences in CRABP-I expression according to disease entity (unilateral MMD vs bilateral MMD vs ACVD), initial presenting symptoms (haemorrhage vs ischaemia) and postoperative haemodynamic change (vascular reserve in single photon emission CT and basal collateral vessels in digital subtraction angiography) were analysed. CRABP-I intensities in bilateral MMD (1.45(0.86-2.52)) were significantly higher than in unilateral MMD (0.91(0.78-1.20)) (p=0.044) or ACVD (0.85(0.66-1.11)) (p=0.004). No significant differences were noted based on the initial presenting symptoms (p=0.687). CRABP-I was not associated with improvement in vascular reserve (p=0.327), but with decrease in basal collateral vessels (p=0.023) postoperatively. Higher CRABP-I in the CSF can be associated with typical bilateral MMD pathogenesis in adults. Additionally, postoperative basal collateral change may be related to the degree of CRABP-I expression.
    Journal of neurology, neurosurgery, and psychiatry 11/2013; · 4.87 Impact Factor
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    ABSTRACT: The fate of the contralateral unaffected side of the surgically treated unilateral moyamoya disease (MMD) in adults has not been well described due to the limited number of cases and the heterogeneous ages and treatment methods. The aim of this study was to evaluate the contralateral angiographic progression rate and its risk factors in homogeneous adult MMD patients who underwent surgical revascularization, with a review of pertinent literature. Forty-one surgically treated unilateral MMD patients were retrospectively evaluated. We reviewed medical and radiological records including data on gender, age, hypertension (HTN), smoking, familial MMD, presenting symptom, surgical method, Suzuki stage, and contralateral progression. Then, we conducted univariate and multivariate analyses to determine risk factors. Six of the 41 cases (14.6 %) exhibited contralateral progression during the mean follow-up of 34 months. Four of those six patients (66.7 %) were asymptomatic. Additional revascularization surgery was performed in the two symptomatic patients. The presence of a contralateral angiographic abnormality on initial angiography was a statistically significant risk factor for progression (OR, 49.00; p = 0.04). Younger age at diagnosis (32.7 ± 7.8 years in progression group vs. 42.5 ± 10.3 years in non-progression group, p = 0.046) was statistically significant in the univariate analysis, but age was not a significant factor in the multivariate analysis (p = 0.82). Other variables, such as gender (p = 0.13), HTN (p = 0.24), smoking (p = 0.47), and familial MMD (p = 0.20), did not show statistical significance. The presence of a contralateral angiographic abnormality on initial angiography was a significant risk factor for progression in surgically treated unilateral adult MMD. Consequently, patients with contralateral abnormalities should be monitored closely.
    Acta Neurochirurgica 11/2013; · 1.55 Impact Factor
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    ABSTRACT: Artifacts introduced by stents limit the value of magnetic resonance (MR) imaging as a follow-up modality after the stent-assisted coil embolization of cerebral aneurysms. To investigate the usefulness of 3 Tesla (3T) time-of-flight (TOF) MR angiography (MRA) for the follow-up evaluation. Twenty-two aneurysms of 20 patients treated with stent-assisted coil embolization were followed up with 3T TOF MRA and digital subtraction angiography (DSA) with three-dimensional rotational angiography (3DRA). The status of coiled aneurysms was compared with 3T TOF MRA and DSA with 3DRA in terms of complete occlusion, residual neck, and residual aneurysm. TOF MRA at 3T was performed 1 day before DSA with 3DRA, with a mean follow-up period of 20.1 ± 10.8 months. Twenty (90.9%) of 22 cases were concordant between the two modalities. The degree of agreement and correlation between them were high (κ = 0.771, P < 0.001; r = 0.832 and P < 0.001). When evaluating the status of residual neck, the sensitivity was 80% (4/5 cases); specificity was not available because there were no cases of complete occlusion. For the status of residual aneurysm, the sensitivity and specificity were 94.1% (16/17 cases) and 100% (all 5 cases), respectively. TOF MRA at 3T with source images could be useful as a non-invasive follow-up modality after the stent-assisted coil embolization of cerebral aneurysms. Further study with a larger patient sample is needed to confirm the effectiveness of 3T TOF MRA.
    Acta Radiologica 09/2013; · 1.33 Impact Factor
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    ABSTRACT: Object Spinal vascular diseases, such as spinal dural arteriovenous fistulas (DAVFs), perimedullary arteriovenous fistulas (AVFs), and spinal arteriovenous malformations (AVMs), are very rare. The authors analyzed the features and treatment outcomes of these conditions. Methods Data from 64 patients were retrospectively reviewed. There were 33 spinal DAVFs (1 patient had 2 lesions), 20 perimedullary AVFs, and 12 spinal AVMs. Clinical features, radiological findings, treatment results, and clinical outcomes were evaluated according to the diseases, subtypes, and treatment modalities. The median duration of follow-up was 20, 42, and 56 months for spinal DAVFs, perimedullary AVFs, and spinal AVMs, respectively. Results Spinal DAVFs showed faster progression of symptoms (median 5, 12, and 36 months for spinal DAVFs, perimedullary AVFs, and spinal AVMs, respectively) and worse neurological status at diagnosis (poor neurological status in 56%, 65%, and 33%, respectively). On MRI, signal voids were demonstrated in all except 1 spinal DAVF. At the last follow-up, 94% of spinal DAVFs, 68% of perimedullary AVFs, and 50% of spinal AVMs were completely obliterated. Favorable clinical outcomes were achieved in 91%, 95%, and 58%, respectively. In detail, the majority (78%) of spinal DAVFs were embolized, resulting in complete obliteration in 92% and favorable clinical outcomes in 92%. Most Type IVa and IVb perimedullary AVFs were surgically treated (71% and 88%), with complete obliterations of 86% and 71%, and favorable clinical outcomes in 100% and 86%, respectively. All Type IVc lesions were embolized with a low cure rate of 40%; however, clinical outcomes were satisfactory. Spinal AVMs were generally embolized (67%), and only glomus-type lesions attained a satisfactory cure rate (80%) and clinical outcome (100%). Conclusions Embolization produced satisfactory outcomes in spinal DAVFs and glomus-type spinal AVMs. Surgery is advantageous in Type IVa and IVb perimedullary AVFs. Palliative embolization can be effective in Type IVc perimedullary AVFs and juvenile spinal AVMs.
    Journal of neurosurgery. Spine 05/2013; · 1.61 Impact Factor
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    ABSTRACT: Intracranial dural arteriovenous fistulas (DAVFs) of the transverse and sigmoid sinuses (TSS) are rare in Asian populations. This study sought to evaluate the treatment outcomes of intracranial TSS DAVFs at a single Asian institute. Between 1989 and 2007, 122 patients presented to the Seoul National University Hospital with intracranial DAVFs; we performed a retrospective analysis of the 38 patients (31.1%) with TSS DAVFs. The common clinical presentations were headache (44.7%), tinnitus (39.5%), and intracranial hemorrhage (26.3%), and 71.1% had Borden type II or III lesions. Two patients were conservatively managed, two underwent surgery, and 34 were treated endovascularly with transarterial embolization (TAE), transvenous embolization (TVE), or both. The complete occlusion rate immediately after treatment was 50%. Of the 31 patients (81.6%) who underwent follow-up angiography, initial complete occlusion was achieved in 51.6%, and, at the last follow-up, the complete occlusion rate was 64.5%, with the surgery and TVE groups achieving 100% occlusion. The clinical cure rate was 34.2%, and 86.8% of patients had a favorable clinical outcome. However, all patients in both the surgery and TVE groups achieved a favorable clinical outcome. Four (26.7%) of 15 lesions with initially partial embolization showed delayed occlusion. Five patients (13.2%) exhibited clinical or angiographic signs of recurrence, and five patients had permanent complications. TSS DAVFs were less common than cavernous sinus DAVFs, unlike in Western countries, but the angiographic and clinical characteristics of TSS DAVFs were similar to those in Western countries. TSS DAVFs were successfully managed with different modalities, but both surgery and TVE were superior to conservative management or TAE.
    Journal of Clinical Neuroscience 01/2013; · 1.25 Impact Factor
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    ABSTRACT: Six patients who experienced transient neurological deteriorations with no evidences of hemorrhage and infarction after encephaloduroarteriogaleosynangiosis for moyamoya disease were evaluated with semiquantitative analysis using brain perfusion SPECT. Postoperative transient neurological deteriorations topographically corresponded to hyperperfusion areas on SPECT. Cerebral blood flows of both the operated hemisphere and focal hyperperfusion area increased significantly after surgery (P = 0.046 and 0.028, respectively), compared with the preoperative ones. Symptomatic cerebral hyperperfusion may occur transiently after indirect revascularization surgery for adult moyamoya disease. Further study is needed to clarify the exact mechanism of cerebral hyperperfusion after indirect surgery.
    Clinical nuclear medicine 01/2013; 38(1):44-6. · 3.92 Impact Factor
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    ABSTRACT: Intracystic bleomycin (ICB) administration is known to be effective in the treatment of cystic craniopharyngiomas (CRPs) and rarely causes serious complications. The authors report a case of vasculopathy after ICB injection for a recurrent cystic CRP. A 5-year-old boy presented with the cystic recurrence of a CRP. A catheter and Ommaya system were inserted into the cyst, followed by a leakage test 2 weeks later. Bleomycin was delivered at 3 mg per week for 14 weeks (total dose 42 mg). Four months later, the patient's activity decreased and right hemiparesis occurred. Magnetic resonance imaging and cerebral angiography demonstrated a recurrent multicystic mass and infarction at the left middle cerebral artery territory with stenosis/occlusion of the left distal internal carotid artery and posterior cerebral artery. During the operation to remove the recurrent cystic mass, fibrotic stenoocclusion of the left intracranial arteries was identified. The cyst was totally removed. However, additional multiple border zone infarctions occurred in the left hemisphere, and the patient became wheelchair bound. Leakage of ICB was considered as the most probable cause of the cerebral vasculopathy and corresponding infarction. A leakage test may not always guarantee a leakage-free status even if the test is negative. Direct bypass surgery should have been considered to prevent a high risk of postoperative infarction in this case of a recurrent CRP with confirmed vasculopathy.
    Journal of Neurosurgery Pediatrics 04/2012; 9(4):394-9. · 1.63 Impact Factor
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    ABSTRACT: Nocardia brain abscess is rare. We report on a unique case of N. farcinica brain abscess in a liver transplant recipient, following Aspergillus fumigatus pneumonia. A 43-year-old liver transplant recipient presented with altered mentality at 2 months after A. fumigates pneumonia. He was successfully treated with surgical removal and antibiotic therapy with trimethoprim-sulfamethoxazole and ceftriaxone.
    Journal of Korean Neurosurgical Society 10/2011; 50(4):396-8. · 0.60 Impact Factor
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    ABSTRACT: The aim of this study was to analyze the treatment outcome of patients with vein of Galen aneurysmal malformations (VGM). Clinical and angiographic data of six consecutive patients with VGM were retrospectively reviewed. VGMs were angiographically classified by Yasargil's method. Treatment outcomes were evaluated. Mean age at initial treatment was 4.4±5.7 months. Angiographic types of VGMs were type II in two patients and type III in four. Three patients had cardiac symptoms and the others were asymptomatic. Two patients were treated with transvenous embolization, three with transarterial embolization, and one was managed conservatively. Two patients died due to venous hypertension few days after transvenous approach. Of three patients who were transarterially embolized, one was completely occluded with Onyx and two were incompletely occluded. During the follow-up period (range, one to six years) two of three patients treated with transarterial approach were asymptomatic and the other showed mild symptoms. One patient who was managed conservatively showed normal performance. Transarterial embolization of VGMs may be better than transvenous approach in terms of the treatment outcome and complication. Further studies are needed because of the rarity of the disease and rapid advancement of endovascular techniques.
    Journal of Korean Neurosurgical Society 09/2011; 50(3):191-4. · 0.60 Impact Factor
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    ABSTRACT: Intradural extraaxial cavernous malformations (CM) are very rare. We report a case of CM originating from the cisternal portion of trigeminal nerve in a 20-year old male. Surgery produced favourable outcome in this case.
    British Journal of Neurosurgery 02/2011; 25(3):339-40. · 0.86 Impact Factor
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    ABSTRACT: A 67-year-old man presented with a case of recurrent subdural hematomas (SDHs) from a pseudoaneurysm at the cortical artery after mild head trauma. He had undergone two episodes of burr hole trephination and evacuation of SDH in a 6-day interval. Review of previous imaging findings and additional cerebral angiography then identified a pseudoaneurysm arising from the precentral branch of the middle cerebral artery. Acute rebleeding suddenly occurred, and the leak point on the cortical artery was completely repaired with a single suture. SDH from pseudoaneurysm after mild head injury is very unusual. The high morbidity and mortality rates necessitate early detection, but the rarity of this type of injury makes detection difficult. If the clinical course is not easily explainable and is worse than the severity of trauma, repeated SDHs occur, or abnormal lesions and/or subarachnoid hemorrhage are identified, computed tomography or magnetic resonance imaging with contrast medium should be performed to identify the underlying cerebrovascular diseases and determine whether cerebral angiography is necessary.
    Neurologia medico-chirurgica 01/2011; 51(3):217-21. · 0.49 Impact Factor
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    ABSTRACT: Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor of infancy and early childhood that occurs mainly in soft tissue and the retroperitoneum. The pathological characteristics of a KHE are fascicles of spindleshaped endothelial cells and slitlike vascular channels with irregular tumor margins. In spite of benign features such as rare mitoses and a low MIB-1 labeling index, a KHE is categorized as an intermediate malignancy because of local invasiveness into adjacent lymph nodes or organs. Resection is the treatment of choice for this type of tumor and adjuvant medical therapy is prepared for the tumor remnants and the associated Kasabach-Merritt syndrome. In this paper the authors report a case of a KHE without Kasabach-Merritt syndrome arising from the right tentorium cerebelli in a 13-month-old male child. The biological behavior of the tumor, including its pathological traits and clinical course, was malignant in nature. This case may be not only the first intracranial extraaxial KHE, but also the first truly malignant variant. Kaposiform hemangioendothelioma should be considered in the differential diagnosis of intracranial and extraaxial tumors.
    Journal of Neurosurgery Pediatrics 03/2009; 3(2):147-50. · 1.63 Impact Factor
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    ABSTRACT: Total laminectomy (TL) is an effective surgical technique for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) along multiple levels. However, kyphosis and probable neurological deterioration have been frequently reported after laminectomy. We analyzed the changes in the cervical curvature after TL and subsequent changes in neurological status. We retrospectively reviewed the records of 14 patients who underwent TL for the treatment of cervical OPLL between Jan. 1998 and Dec. 2003. TL was selected according to the previously determined criteria. The curvature of the cervical spine was visualized on a lateral cervical spine X-ray and measured using Ishihara's Curvature Index (CI) before the operation and at the last follow-up examination. Perioperative neurological status was estimated using the modified Japanese Orthopedic Association score and the Improvement Rate (IR) at the same time as the images were evaluated. The mean age of the patients was 57 years, the male/female ratio was 10:4, and the mean follow-up period was 41 months. The mean number of OPLL was 4.9, and the mean number of operated levels was also 4.9. The CI decreased after TL (p=0.002), which was indicative of a kyphotic change. However, this kyphotic change showed no correlation with the length of the follow-up period, number of operated levels and preoperative CI. Neurological examination at the last follow-up showed an improved neurological status in all patients (p=0.001). There was no neurological deterioration in any case during the follow-up period. Moreover, there was no correlation between IR and the degree of kyphotic change. Postoperative complications, such as C5 radiculopathy and epidural bleeding, resolved spontaneously without neurological sequelae. Kyphotic change was observed in all but one patient who underwent TL for the treatment of cervical OPLL. However, we did not find any contributing factors to kyphosis or evidence of postoperative neurological deterioration.
    Journal of Korean Neurosurgical Society 07/2008; 43(6):259-64. · 0.56 Impact Factor

Publication Stats

22 Citations
34.42 Total Impact Points

Institutions

  • 2011–2013
    • Kangwon National University
      • Department of Neurosurgery
      Shunsen, Gangwon, South Korea
    • Kangwon National University Hospital
      Shunsen, Gangwon, South Korea
  • 2008–2013
    • Seoul National University Hospital
      • • Department of Neurosurgery
      • • Department of Internal Medicine
      Seoul, Seoul, South Korea
    • Seoul National University
      • Department of Neurosurgery
      Seoul, Seoul, South Korea