Seung Hwan Yoon

Inha University, Seoul, Seoul, South Korea

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Publications (36)58.1 Total impact

  • Article: A Comparison of the Somatometric Measurements of Adolescent Males with and Without Idiopathic Scoliosis.
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    ABSTRACT: STUDY DESIGN:: Prospective study comparing the somatometric measurements of young males with normal spinal curves and with adolescent idiopathic scoliosis (AIS) with respect to the severity of AIS. OBJECTIVE:: To access the somatometric measurements of young males with normal spinal curves and with AIS using the conscription data. SUMMARY OF BACKGROUND DATA:: The progression of AIS is closely correlated with longitudinal growth during puberty. Although abnormal growth in female AIS patients has been well investigated, but the growth of male AIS patients has not been well reported. METHODS:: During Korean conscription, 409 adolescent males with a normal spinal curvature and 420 adolescent males with AIS were enrolled. Those with AIS were grouped according to the severity of scoliosis using Cobb angles, according to the guidelines issued by the Korean military directorate. Group somatometric measurements, such as, body height, corrected body height (corrected using Bjure's equation), body weight, and body mass index (BMI) were compared. RESULTS:: Uncorrected heights were insignificantly different (P=0.234), but corrected heights, body weights, and BMIs were all significantly different between the normal and all AIS groups (P<0.001) (in AIS corrected height was greater and body weight and BMIs corrected or not corrected for height were lower). Cobb angles was not related to corrected body height or BMI, but was related to weight. Body weight was significantly less in the severe AIS group (Cobb angle >40 degrees) than in the mild or moderate AIS group (P<0.042). CONCLUSION:: In Korean male AIS, significantly different somatometric results were observed, namely, a greater corrected height and lower body weight and BMIs corrected or not corrected for height. Furthermore, body weight was significantly lower in the severe group than in the moderate group. This study shows abnormal growth is observed in male AIS and that body weight is closely correlated with AIS severity.
    Journal of spinal disorders & techniques 03/2013; · 1.21 Impact Factor
  • Article: The psychopathological influence of adolescent idiopathic scoliosis in korean male : an analysis of multiphasic personal inventory test results.
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    ABSTRACT: There are few published studies which have documented psychopathological abnormalities in patients with of adolescent idiopathic scoliosis (AIS) The aim of this study was to evaluate the psychopathological influence of AIS in Korean 19-year-old males. The authors compared the Korean military multiphasic personal inventory (KMPI) military profiles of 105 AIS cases (more than 10 degrees of Cobb's angle without surgical treatment) with the KMPI profiles of 108 normal controls. The AIS group was split depending on Cobb's angle to further evaluate this relation by the severity of AIS. A significantly decreased result on the faking-good response scale and an significantly increased result on the faking-bad response were observed in the AIS group compared to the control (p<0.012). The neurosis scale results, including anxiety, depression and somatization symptoms, were significantly increased in the AIS group compared to the control (p<0.010). The severity level of personality disorder and schizophrenia were also significantly increased in the AIS group (p<0.010). Differences in KMPI scale scores were not related to the severity of AIS. Young males with AIS tend to have abnormal results on the multiphasic personal inventory test compared to normal volunteers, suggesting that AIS may be related to psychopathology in the young male group in Korea. Although these psychopathology in AIS were differently observed compared to normal controls, but not interfered with military life. Clinicians are recommended to pay attention the psychopathological traits of patients with AIS.
    Journal of Korean Neurosurgical Society 01/2013; 53(1):13-8. · 0.60 Impact Factor
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    Article: The psychopathological influence of congenital heart disease in korean male adolescents: an analysis of multiphasic personal inventory test results.
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    ABSTRACT: Purpose: The aim of this study was to evaluate the psychopathological influence of congenital heart disease (CHD) in Korean 19-year-old males. Materials and Methods: The authors compared the Korean military multiphasic personal inventory (KMPI) military profiles of 211 CHD cases (atrial septal defect, ventricular septal defect, patent ductus arteriosus, or combined CHD) with the KMPI profiles of 300 normal controls. The CHD group was also divided according to whether or not the subjects had undergone open cardiac surgery in order to evaluate the psychopathological effects of an operation among the subjects. Results: A decreased result on the faking-good response scale and an increased result on the faking-bad response were observed in the CHD group compared to the control (p<0.01). The neurosis scale results, including anxiety, depression and somatization symptoms, were markedly increased in the CHD group compared to the control (p<0.01). The severity level of personality disorder was also increased in the CHD group (p<0.001). Differences in KMPI scale scores were not related to open cardiac surgery history. Conclusion: In this study, young males with CHD tended to report more abnormal results on the multiphasic personal inventory test in comparison to normal subjects, suggesting that CHD may be related to psychopathology in young males in Korea. Therefore, clinicians are recommended to evaluate the psychopathological traits of patients with CHD.
    Yonsei medical journal 11/2012; 53(6):1107-12. · 0.77 Impact Factor
  • Article: Usefulness of chest radiographs for scoliosis screening: a comparison with thoraco-lumbar standing radiographs.
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    ABSTRACT: Purpose: The purposes of this study were to evaluate the usefulness and limitations of chest radiographs in scoliosis screening and to compare these results with those of thoraco-lumbar standing radiographs (TLSR). Materials and Methods: During Korean conscription, 419 males were retrospectively examined using both chest radiographs and TLSR to confirm the scoliosis and Cobb angle at the Regional Military Manpower. We compared the types of spinal curves and Cobb angles as measured from different radiographs. Results: In the pattern of spinal curves, the overall matching rate of chest radiographs using TLSR was about 58.2% (244 of 419 cases). Cobb angle differences between chest radiographs and TLSR with meaningful difference was observed in 156 cases (37.2%); a relatively high proportion (9.5%) of Cobb angle differences more than 10 degrees was also observed. The matching rate of both spinal curve types and Cobb angle accuracy between chest radiographs and TLSR was 27.9% (117 among 419 cases). Chest radiographs for scoliosis screening were observed with 93.94% of sensitivity and 61.67% of specificity in thoracic curves; however, less than 40% of sensitivity (38.27%, 20.00%, and 25.80%) and more than 95% of specificity (97.34%, 99.69%, and 98.45%) were observed in thoraco- lumbar, lumbar, and double major curves, respectively. Conclusion: The accuracy of chest radiographs for scoliosis screening was low. The incidence of thoracic curve scoliosis was overestimated and lumbar curve scoliosis was easily missed by chest radiography. Scoliosis screening using chest radiography has limited values, nevertheless, it is useful method for detecting thoracic curve scoliosis.
    Yonsei medical journal 11/2012; 53(6):1183-9. · 0.77 Impact Factor
  • Article: Improvement in sensory function via granulocyte-macrophage colony-stimulating factor in rat spinal cord injury models.
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    ABSTRACT: Object The aim in this study was to determine whether granulocyte-macrophage colony-stimulating factor (GM-CSF) leads to sensory improvement in rat spinal cord injury (SCI) models. Methods Thirty male Sprague-Dawley rats were included in this study: 10 in the sham group (laminectomy alone without SCI), 10 in the SCI group (SCI treated with phosphate-buffered saline), and 10 in the GM-CSF treatment group (SCI treated with GM-CSF). A locomotor function test and pain sensitivity test were conducted weekly for 9 weeks after SCI or sham injury. Spinal tissue samples from all rats were immunohistochemically examined for the expression of calcitonin gene-related peptide (CGRP) and abnormal sprouting at Week 9 post-SCI. Results Granulocyte-macrophage colony-stimulating factor treatment improves functional recovery after SCI. In the tactile withdrawal threshold and frequency of the hindlimb paw, the GM-CSF group always responded with a statistically significant lower threshold than the SCI group 9 weeks after SCI (p < 0.05). The response of the forelimb and hindlimb paws to cold in the GM-CSF group always reflected a statistically significant lower threshold than in the SCI group 9 weeks after injury (p < 0.05). Decreased CGRP expression, observed by density and distribution area, was noted in the GM-CSF group (optical density 113.5 ± 20.4) compared with the SCI group (optical density 143.1 ± 18.7; p < 0.05). Conclusions Treatment with GM-CSF results in functional recovery, improving tactile and cold sense recovery in a rat SCI model. Granulocyte-macrophage colony-stimulating factor also minimizes abnormal sprouting of sensory nerves after SCI.
    Journal of neurosurgery. Spine 10/2012; · 1.61 Impact Factor
  • Article: The impact of primary spontaneous pneumothorax on multiphasic personal inventory test results in young South Korean males.
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    ABSTRACT: Few reports have documented psychopathological abnormalities in patients with primary spontaneous pneumothorax (PSP). We analyzed the results of a multiphasic personal inventory test to investigate the psychopathologic impact of PSP in young Korean males. The authors reviewed the results of a Korean military multiphasic personal inventory (KMPI) administered to military conscripts in South Korea. A total of 234 young males participated in this study. The normal volunteer group (n=175) comprised individuals who did not have any lung disease. The PSP group (n=59) included individuals with PSP. None of the examinees had any psychological problems. The KMPI results of both groups were compared. There were more abnormal responses in the PSP group (17.0%) than the normal volunteer group (9.1%, p=0.002). The anxiety scale and depression scale scores of the neurosis category were greater for the PSP group than the normal group (p=0.039 and 0.014, respectively). The personality disorder and paranoia scale scores of the psychopathy category were greater for the PSP group than the normal group (p=0.007 and 0.018, respectively). Young males with PSP may have greater tendencies to suffer from anxiety, depression, personality disorders, and paranoia compared to normal individuals. Clinicians should be advised to evaluate the psychopathological aspects of patients with PSP.
    Yonsei medical journal 09/2012; 53(5):901-5. · 0.77 Impact Factor
  • Article: Interobserver and Intraobserver Reliability of Sub-Axial Injury Classification and Severity Scale between Radiologist, Resident and Spine Surgeon.
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    ABSTRACT: The sub-axial injury classification (SLIC) and severity scale was developed to decide whether to operate the cervical injured patient or not, but the reliability of SLIC and severity scale among the different physicians was not well known. Therefore, we evaluated the reliability of SLIC among a spine surgeon, a resident of neurosurgery and a neuro-radiologist. In retrograde review in single hospital from 2002 to 2009 years, 75 cases of sub-axial spine injured patients underwent operation. Each case was blindly reviewed for the SLIC and severity scale by 3 different observers by two times with 4 weeks interval with randomly allocated. The compared axis was the injury morphology score, the disco-ligamentous complex score, the neurological status score and total SLIC score; the neurological status score was derived from the review of medical record. The kappa value was used for the statistical analysis. Interobserver agreement of SLIC and severity scale was substantial agreement in the score of injury morphology [intraclass correlation (ICC)=0.603] and total SLIC and severity sacle (ICC value=0.775), but was fair agreement in the disco-ligamentous complex score (ICC value=0.304). Intraobserver agreements were almost perfect agreement in whole scales with ICC of 0.974 in a spine surgeon, 0.948 in a resident of neurosurgery, and 0.963 in a neuro-radiologist. The SLIC and severity scale is comprehensive and easily applicable tool in spine injured patient. Moreover, it is very useful tool to communicate among spine surgeons, residents of neurosurgery and neuro-radiologists with sufficient reproducibility.
    Journal of Korean Neurosurgical Society 09/2012; 52(3):200-3. · 0.60 Impact Factor
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    Article: Missed diagnosis of syrinx.
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    ABSTRACT: Prospective, randomized, controlled human study. We checked the proportion of missed syrinx diagnoses among the examinees of the Korean military conscription. A syrinx is a fluid-filled cavity within the spinal cord or brain stem and causes various neurological symptoms. A syrinx could easily be diagnosed by magnetic resonance image (MRI), but missed diagnoses seldom occur. In this study, we reviewed 103 cases using cervical images, cervical MRI, or whole spine sagittal MRI, and syrinxes was observed in 18 of these cases. A review of medical certificates or interviews was conducted, and the proportion of syrinx diagnoses was calculated. The proportion of syrinx diagnoses was about 66.7% (12 cases among 18). Missed diagnoses were not the result of the length of the syrinx, but due to the type of image used for the initial diagnosis. The missed diagnosis proportion of the syrinx is relatively high, therefore, a more careful imaging review is recommended.
    Asian spine journal 03/2012; 6(1):1-5.
  • Article: Outcome evaluation with signal activation of functional MRI in spinal cord injury.
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    ABSTRACT: The authors investigated the changes of cortical sensorimotor activity in functional MRI (fMRI) and functional recovery in spinal cord injury (SCI) patients who had been treated by bone marrow cell transplantation. Nineteen patients with SCI were included in this study; ten patients with clinical improvement and nine without. The cortical sensorimotor activations were studied using the proprioceptive stimulation during the fMRI. Diagnostic accuracy of fMRI with neurological improvement was 70.0% and 44.4% for sensitivity and specificity, respectively. Signal activation in the ipsilateral motor cortex in fMRI was commonly observed in the clinically neurological improved group (p-value=0.002). Signal activation in the contralateral temporal lobe and basal ganglia was more commonly found in the neurological unimproved group (p-value<0.001). Signal activation in other locations was not statistically different. In patients with SCI, activation patterns of fMRI between patients with neurologic recovery and those without varied. Such plasticity should be considered in evaluating SCI interventions based on behavioral and neurological measurements.
    Journal of Korean Neurosurgical Society 09/2011; 50(3):209-15. · 0.60 Impact Factor
  • Article: Influence of history of brain disease or brain trauma on psychopathological abnormality in young male in Korea : analysis of multiphasic personal inventory test.
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    ABSTRACT: The purpose of this study is to confirm whether brain disease or brain trauma actually affect psychopathology in young male group in Korea. The authors manually reviewed the result of Korean military multiphasic personal inventory (KMPI) in the examination of conscription in Korea from January 2008 to May 2010. There were total 237 young males in this review. Normal volunteers group (n=150) was composed of those who do not have history of brain disease or brain trauma. Brain disease group (n=33) was consisted of those with history of brain disease. Brain trauma group (n=54) was consisted of those with history of brain trauma. The results of KMPI in each group were compared. Abnormal results of KMPI were found in both brain disease and trauma groups. In the brain disease group, higher tendencies of faking bad response, anxiety, depression, somatization, personality disorder, schizophrenic and paranoid psychopathy was observed and compared to the normal volunteers group. In the brain trauma group, higher tendencies of faking-good, depression, somatization and personality disorder was observed and compared to the normal volunteers group. Young male with history of brain disease or brain trauma may have higher tendencies to have abnormal results of multiphasic personal inventory test compared to young male without history of brain disease or brain trauma, suggesting that damaged brain may cause psychopathology in young male group in Korea.
    Journal of Korean Neurosurgical Society 08/2011; 50(2):114-8. · 0.60 Impact Factor
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    Article: Time-related changes in detrusor overactivity in awake rats with spinal cord injury observed by simultaneous registrations of intravesical and intraabdominal pressures.
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    ABSTRACT: To compare the physical characteristics of detrusor overactivity (DO) induced by intravesical infusion of saline in awake, sham rats and rats with chronic spinal cord injury (SCI), by simultaneous registrations of intravesical and intraabdominal pressures. Male Sprague-Dawley rats, normal or with a spinal vascular clip at the level of Th9, were investigated cystometrically 1 and 4 weeks after SCI. Intravesical pressure (IVP) and intraabdominal pressure (IAP) were recorded simultaneously to evaluate true DO. During the filling phase, the event of IVP rises, defined as increments that exceeded 2 cmH(2)O from baseline, were determined as DO according to the absence of simultaneous changes in IAP. All SCI rats exhibited DO during the filling phase, which was not shown in sham rats. The frequency and pressure of DO had a tendency to decrease with time. The DO frequency of SCI rats after 4 weeks (0.9±0.2 min(-1)) was decreased compared with that after 1 week (2.1±0.4 min(-1); P<0.05). The DO pressure of SCI rats after 4 weeks (8.4±1.9 cmH(2)O) was decreased compared with that after 1 week (11.6±2.9 cmH(2)O; P>0.05). Cystometric studies in awake male SCI rats showed some significant changes in bladder function after SCI. All SCI rats exhibited DO during the filling phase, and showed different physical characteristics of DO over the course of time. The neurological basis of these time-related changes remains poorly understood, but may provide important prognostic information about long-term urological management in SCI patients.
    International neurourology journal 03/2011; 15(1):19-24.
  • Article: Dual and single memory rod construct comparison in an animal study.
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    ABSTRACT: Single- or dual-shape memory metal (nitinol) rods were used to create spinal deformity in a mini-pig model. To determine the practicality of employing nitinol rods for clinical spinal deformity correction using an animal deformity creation model. Nitinol rods can, theoretically, be approximated to curved spines when cooled/malleable, achieving spinal deformity correction on warming and returning to their original (straight) shape. Square cross-sectional rods may allow transverse plane correction. Single-rod constructs could achieve greater deformity correction clinically, whereas dual rods provide lower implant failure risk. The clinical feasibility and potential effectiveness of single versus dual nitinol rod constructs in creating spinal deformity in an animal model was studied. Twenty mature mini-pigs were grouped: single rod with screws locked to the rod, single rod with screws unlocked, dual rods--locked, dual rods--unlocked. Square nitinol rods (80° manufactured curvature) were cooled (-20°C), straightened, placed into multilevel square-headed pedicle screws and warmed (40°C). Serial radiographs followed deformity creation over 12 weeks. Single versus dual rods, locked versus unlocked rods were compared (P<0.01). Computed tomography showed screw placement and fusion (none attempted). Preoperative and 12-week postoperative serum nickel levels were compared (P<0.05). Scoliotic deformities were created immediately in single and dual rod groups (28°±8°, 26°±7°; P=0.59); locked and unlocked groups (24°±7°, 30°±6°; P=0.08). At final follow-up, there was no difference between single and dual rods (31°±11°, 28°±10°; P=0.58); unlocked rods and locked rods were 34.9°±9.4° and 25.0°±8.1° (P=0.02). No implant failure occurred, however, the aggressive rod contour led to vertebral endplate fractures. Serum nickel 12 weeks post rod placement were unchanged from preop levels (5.1±0.6 μg/L, 4.7±0.2 μg/L, P=0.10). Nitinol rods, reliable in creating spinal deformity in an animal model, could potentially straighten deformed spines. Square rods, facilitated by markedly reduced stiffness when cooled, have the potential to predictably perform axial plane correction.
    Spine 01/2011; 36(14):E904-13. · 2.08 Impact Factor
  • Article: Primary paravertebral low-grade fibromyxoid sarcoma.
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    ABSTRACT: The authors report a 58-year-old woman with low-grade fibromyxoid sarcoma primarily located in the right paravertebral area with extension to L4 neural foramen. The patient complained lower back pain with radiating pain along the posterolateral aspect of the right lower leg. She underwent subtotal surgical removal and Cyber Knife therapy. Diagnosis was made by strikingly characteristic microscopic appearance of a bland spindle cell sarcoma which contained numerous giant collagen rosettes and was also supported by immunohistological findings. The diagnostic image findings and literatures are reviewed and discussed.
    Journal of Korean Neurosurgical Society 11/2010; 48(5):461-4. · 0.60 Impact Factor
  • Article: A Comparison of fixed-hole and slotted-hole dynamic plates for anterior cervical discectomy and fusion.
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    ABSTRACT: A retrospective review of clinical data at 1 institution was performed. To compare the clinical and radiologic outcomes between fixed-hole and slotted-hole dynamic cervical plates. Anterior cervical plating is commonly used to increase stability and promote spinal fusion. Two techniques, fixed-hole dynamic plating that uses variable angled screws and slotted-hole dynamic plating that permits sliding, are viable options, but there have been no clinical studies comparing their effectiveness. Fifty-six patients at 1 institution having anterior cervical discectomy and fusion for degenerative disease over a 5-year period were entered into this study. Surgeries were performed with 1 of the dynamic plates for 1 to 3 levels. For the slotted-hole dynamic plate group, a slotted-hole plate was used (ABC, Aesculap, Tuttlingen, Germany or C-tek, Biomet, Parssipany, NJ) and for the fixed-hole dynamic plated group, a variable angled screw was used (C-tek, Biomet, Parssipany, NJ). Radiographic measurements included were graft subsidence, lordotic angle change from each end plate of fusion construct, and implant translation from end plates after a minimum of 12 months follow-up. Fusion state and clinical outcome using Odom's criteria were also evaluated. Demographics were not different among patient populations. The average age of the patients was 51.0 years (range: 27 to 77 y). Mean follow-up period was 20.6 months (range: 12 to 41 mo). Slotted-hole dynamic plates were used for 29 patients (ABC plate, 17; C-tek plate, 12) and fixed-hole dynamic plates for 27 patients. Clinical outcomes and pseudoarthrosis rates were similar for both types of plates. Radiographic measurements showed a statistically significant increased incidence of graft subsidence and implant translation with the slotted-hole dynamic plates. Loss of lordosis was also greater in the slotted-hole dynamic plated group, although the difference was not statistically significant. The use of a fixed-hole dynamic plate is more favorable in regards to graft subsidence and implant translation in the follow-up period, although clinical outcome and fusion rates are similar in patients with either the fixed-hole or slotted-hole dynamic plates.
    Journal of spinal disorders & techniques 02/2010; 23(1):22-6. · 1.21 Impact Factor
  • Article: Evaluation of Spinal Fusion Using Bone Marrow Derived Mesenchymal Stem Cells with or without Fibroblast Growth Factor-4.
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    ABSTRACT: In this study, the authors assessed the ability of rat bone marrow derived mesenchymal stem cells (BMDMSCs), in the presence of a growth factor, fibroblast growth factor-4 (FGF-4) and hydroxyapatite, to act as a scaffold for posterolateral spinal fusion in a rat model. Using a rat posterolateral spine fusion model, the experimental study comprised 3 groups. Group 1 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite only. Group 2 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite containing 1 x 10(6)/ 60 microL rat of BMDMSCs. Group 3 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite containing 1 x 10(6)/ 60 microL of rat BMDMSCs and FGF-4 1 microG to induce the bony differentiation of the BMDMSCs. Rats were assessed using radiographs obtained at 4, 6, and 8 weeks postoperatively. After sacrifice, spines were explanted and assessed by manual palpation, high-resolution microcomputerized tomography, and histological analysis. Radiographic, high-resolution microcomputerized tomographic, and manual palpation revealed spinal fusion in five rats (83%) in Group 2 at 8 weeks. However, in Group 1, three (60%) rats developed fusion at L4-L5 by radiography and two (40%) by manual palpation in radiographic examination. In addition, in Group 3, bone fusion was observed in only 50% of rats by manual palpation and radiographic examination at this time. The present study demonstrates that 0.08 gram of hydroxyapatite with 1 x 10(6)/ 60 microL rat of BMDMSCs induced bone fusion. FGF-4, added to differentiate primitive 1 x 10(6)/ 60 microL rat of BMDMSCs did not induce fusion. Based on histologic data, FGF-4 appears to induce fibrotic change rather than differentiation to bone by 1 x 10(6)/ 60 microL rat of BMDMSCs.
    Journal of Korean Neurosurgical Society 10/2009; 46(4):397-402. · 0.60 Impact Factor
  • Article: GM-CSF inhibits glial scar formation and shows long-term protective effect after spinal cord injury.
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    ABSTRACT: This study investigated the effects of granulocyte macrophage-colony stimulating factor (GM-CSF) on the scar formation and repair of spinal cord tissues in rat spinal cord injury (SCI) model. Sprague-Dawley male rats (8 weeks old) were randomly divided into the sham-operated group, spinal cord injury group, and injury with GM-CSF treated group. A spinal cord injury was induced at T9/10 levels of rat spinal cord using a vascular clip. GM-CSF was administrated via intraperitoneal (IP) injection or on the dural surface using Gelfoam at the time of SCI. The morphological changes, tissue integrity, and scar formation were evaluated until 4 weeks after SCI using histological and immunohistochemical analyses. The administration of GM-CSF either via IP injection or local treatment significantly reduced the cavity size and glial scar formation at 3-4 weeks after SCI. GM-CSF also reduced the expression of core proteins of chondroitin sulfate proteoglycans (CSPGs) such as neurocan and NG2 but not phosphacan. In particular, an intensive expression of glial fibriallary acidic protein (GFAP) and neurocan found around the cavity at 4 weeks was obviously suppressed by GM-CSF. Immunostaining for neurofilament (NF) and Luxol fast blue (LFB) showed that GM-CSF preserved well the axonal arrangement and myelin structure after SCI. The expression of GAP-43, a marker of regenerating axons, also apparently increased in the rostral grey matter by GM-CSF. These results suggest that GM-CSF could enhance long-term recovery from SCI by suppressing the glial scar formation and enhancing the integrity of axonal structure.
    Journal of the Neurological Sciences 12/2008; 277(1-2):87-97. · 2.35 Impact Factor
  • Article: Time course of symptom disappearance after microvascular decompression for hemifacial spasm.
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    ABSTRACT: This study is to investigate time course of symptom disappearance in patients whose spasm relieved completely after microvascular decompression (MVD). Of 115 patients with hemifacial spasm (HFS) who underwent MVD from April 2003 to December 2006, 89 patients who had no facial paralysis after operation and showed no spasm at last follow-up more than 1.5 years after operation were selected. Symptom disappearance with time after MVD was classified into type 1 (symptom disappearance right after operation), type 2 (delayed symptom disappearance) and type 3 (unusual symptom disappearance). Type 2 was classified into type 2a (with postoperative silent period) and type 2b (without silent period). Type 1, type 2a, type 2b and type 3 were 38.2%, 48.37%, 12.4% and 1.1%, respectively. Delayed disappearance group (type 2) was 60.7%. Post-operative symptom duration in all cases ranged from 0 to 900 days, average was 74.6 days and median was 14 days. In case of type 2, average post-operative symptom duration was 115.1 days and median was 42 days. Five and 3 patients required more than 1 year and 2 years, respectively, until complete disappearance of spasm. In type 2a, postoperative silent period ranged from 1 to 10 days, with an average of 2.4 days. Surgeons should be aware that delayed symptom disappearance after MVD for HFS is more common than it has been reported, silent period can be as long as 10 days and time course of symptom disappearance is various as well as unpredictable.
    Journal of Korean Neurosurgical Society 11/2008; 44(4):245-8. · 0.60 Impact Factor
  • Article: Comparative Study of Outcomes between Shunting after Cranioplasty and in Cranioplasty after Shunting in Large Concave Flaccid Cranial Defect with Hydrocephalus.
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    ABSTRACT: The cranioplasty and ventriculoperitoneal (VP) shunt operation have been used to treat a large cranial defect with posttraumatic hydrocephalus (PTH). The aim of this study was to evlauate the difference of outcomes between in the shunting after the cranioplasty (group 1) and the cranioplasty after the shunting (group 2) in a large flaccid cranial defect with PTH. In this study, a retrospective review was done on 23 patients undergoing the cranioplasty and VP shunt operation after the decompressive craniectomy for a refractory intracranial hypertension from 2002 to 2005. All of 23 cases had a large flaccid concave cranial defect and PTH. Ten cases belong to group 1 and 13 cases to group 2. The outcomes after operations were compared in two groups 6 months later. The improvement of Glasgow outcome scale (GOS) was seen in 8 cases (80.0%) of total 10 cases in group 1, and 6 cases (46.2%) of 13 cases in group 2. Three (75.0%) of 4 cases with hemiparesis in group 1 and 3 of 6 cases (50.0%) in group 2 were improved. All cases (2 cases) with decrease of visual acuity were improved in each group. Dysphasia was improved in 3 of 5 cases (60%) in group 1 and 4 of 6 cases (66.6%) in group 2. These results suggest that outcomes in group 1 may be better than in group 2 for a large flaccid concave cranial defect with PTH.
    Journal of Korean Neurosurgical Society 11/2008; 44(4):211-6. · 0.60 Impact Factor
  • Article: Comparison between 4.0-mm stainless steel and 4.75-mm titanium alloy single-rod spinal instrumentation for anterior thoracoscopic scoliosis surgery.
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    ABSTRACT: Retrospective review of a consecutive, single surgeon case series. To compare minimum 2-year postoperative outcomes between 4.0-mm stainless steel and 4.75-mm titanium alloy single-rod anterior thoracoscopic instrumentation for the treatment of thoracic idiopathic scoliosis. Advances in anterior thoracoscopic spinal instrumentation for scoliosis have attempted to mitigate the postoperative complications of rod failure, pseudarthrosis, and deformity progression. Biomechanical data suggest that the 4.75-mm titanium construct has a lower risk of fatigue failure compared to the 4.0-mm stainless steel construct. Sixty-four consecutive anterior thoracoscopic spinal instrumentation cases in patients with thoracic scoliosis performed by a single surgeon and with minimum 2-year follow-up were retrospectively reviewed. The first 34 cases used a 4.0-mm stainless steel (SS) construct, whereas the subsequent 30 cases used a 4.75-mm titanium (Ti) alloy instrumentation system. The first 10 SS cases and the first 5 Ti cases were excluded from the statistical comparison to account for a potential learning curve effect. A multivariate analysis of variance (P < 0.05) was used to compare radiographic, perioperative, and postoperative complication data between patients surgically treated with the 2 different instrumentation systems. Patients in the SS group (n = 24) underwent surgery from 2000 to 2001, whereas patients in the Ti group (n = 25) underwent surgery from 2002 to 2004. The mean age at surgery, gender ratio, length of hospitalization, estimated blood loss, and operative time were not statistically different between the 2 patient groups (P > 0.13). The average follow-up in the SS group was, however, significantly longer than in the Ti group (4.0 +/- 1.4 years vs. 2.3 +/- 1.0 years; P = 0.001). Preop main thoracic Cobb angles were similar between the 2 groups (P = 0.62); however, the 2-year main thoracic Cobb was significantly smaller (P = 0.03) and the 2-year percent correction was significantly greater in the Ti group (P = 0.03). Five patients (21%) in the SS group had a pseudarthrosis, 3 (13%) experienced rod failure, and 2 (8%) required a revision posterior spinal fusion. In the Ti group, 2 patients (8%) had a pseudarthrosis, and no patient experienced rod failure or required a revision procedure. Although the average follow-up in the Ti group was significantly shorter than in the SS group, the 4.75-mm titanium alloy construct resulted in improved maintenance of deformity correction at 2-years postop and a lower incidence of instrumentation-related complications (pseudarthrosis, rod breakage, and surgical revisions) compared to the 4.0-mm stainless steel construct. Improved outcomes with the titanium alloy construct are likely because of the mechanical properties of the implant, refined patient selection criteria, and greater surgical experience gained with time.
    Spine 10/2008; 33(20):2173-8. · 2.08 Impact Factor
  • Article: Comparison of lentiviral and adenoviral gene therapy for spinal fusion in rats.
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    ABSTRACT: Rat spinal fusion model. This study aimed to compare the efficacy of lentiviral gene therapy, and adenoviral gene therapy in inducing spinal fusion in an immune competent rat spinal fusion model. Recombinant bone morphogenetic proteins (BMPs) have also been used for spinal fusion successfully in clinical trials. However, large doses of BMPs are required to induce adequate bone repair. Hence, regional gene therapy may be a more efficient method to deliver proteins to a specific anatomic site. Recently, lentiviral vectors based on human immunodeficiency virus have been developed for gene therapy. However, lentiviral gene therapy for spinal fusion has not been compared with adenoviral gene therapy. Lewis rats were divided into 7 groups. group I, II, III, and IV rats were implanted with a collagen sponge containing rat bone marrow cells (RBMCs) transfected with Lenti-BMP-2, Adeno-BMP-2, Lenti-GFP, Adeno-LacZ, respectively. Group V, VI, and VII rats were implanted with a collagen sponge containing recombinant BMP-2, a collagen sponge containing untransfected RBMCs, and a collagen sponge alone, respectively. The rats were assessed at 4, 6, and 8 weeks after implantation. After sacrificing the rats, their spines were explanted and assessed by manual palpation, high-resolution microcomputed tomography, and histologic analysis. Spinal fusion was observed in all animals in group I, II, and V rats at 8 weeks. None of the rats in groups III, IV, VI, and VII showed spinal fusion. The volumes of the new bone in the area between the L4 and L5 transverse processes were greater in group I rats than in group II, and V rats with a significant difference. BMP-2-producing RBMCs developed using lentiviral gene transfer induced more abundant bone within the fusion mass than the RBMCs transduced via adenoviral gene transfer and recombinant protein therapy.
    Spine 07/2008; 33(13):1410-7. · 2.08 Impact Factor

Institutions

  • 2008–2012
    • Inha University
      • Department of Neurosurgery
      Seoul, Seoul, South Korea
    • University of California, Los Angeles
      • Department of Orthopaedic Surgery
      Los Angeles, CA, USA
    • University of California, San Diego
      • Department of Orthopaedic Surgery
      San Diego, CA, USA
  • 2010
    • Wooridul Spine Hospital Group
      Seoul, Seoul, South Korea
  • 2004–2008
    • Inha University Hospital
      Sinhyeon, South Gyeongsang, South Korea