Byung Kwan Choi

Pusan National University, Tsau-liang-hai, Busan, South Korea

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Publications (45)40.48 Total impact

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    ABSTRACT: The purpose of this study is to assess the technical feasibility and clinical efficacy of percutaneous transluminal angioplasty and stenting (PTAS) for symptomatic stenosis of the intracranial extradural (petrous and cavernous) internal carotid artery (ICA).Review of medical records identified 26 consecutive patients who underwent PTAS using a balloon-expandable coronary stent (n = 15, 57.7%) or a Wingspan self-expandable stent (n = 11, 42.3%) for treatment of severe stenosis (>70%) involving the intracranial extradural ICA. The inclusion criteria were transient ischemic attack with an ABCD(2) score of ≥3 (n = 12, 46.2%) or minor stroke with an NIHSS score of ≤4 (n = 14, 53.8%). Technical success rates, complications, and angiographic and clinical outcomes were analyzed retrospectively.PTAS was technically successful in all patients. The mean stenosis ratio decreased from 77.1% to 10.0% immediately after PTAS. The overall incidence of procedural complications was 23.1%, and the postoperative permanent morbidity/mortality rate was 7.7%. A total of 22 patients were tracked over an average period of 29.9 months. During the observation period, 20 patients (90.9%) had no further cerebrovascular events and stroke recurrence occurred in two patients (9.1%), resulting in an annual stroke risk of 3.7%. Two cases (11.1%) of significant in-stent restenosis (>50%) were found on follow-up angiography (n = 18).PTAS for severe stenosis (>70%) involving the intracranial extradural ICA showed a good technical feasibility and favorable clinical outcome in patients with transient ischemic attack or minor stroke. © The Author(s) 2015.
    Interventional Neuroradiology 06/2015; DOI:10.1177/1591019915582379 · 0.73 Impact Factor
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    ABSTRACT: Carbon nanotubes (CNTs) are promising candidates as novel scaffolds for peripheral nerve regeneration. Schwann cells (SCs) are attractive therapeutic targets due to their pivotal role in peripheral nerve regeneration, but primary SCs have limitations for clinical application. However, adipose-derived stem cells (ASCs) may differentiate into Schwann-like cells. The present study assesses the potential applicability of multi-wall CNTs (MWNTs) composited with polydimethylsiloxane (PDMS), which were then seeded with differentiated adipose-derived stem cells (dASCs) to promote neuronal differentiation and growth. Aqueous MWNT dispersion was filtered, and the PDMS/MWNT sheets were prepared using a simple printing-transfer method. Characterization of PDMS/MWNT sheets indicated their unique physical properties, such as superior mechanical strength and electroconductivity, compared with bare PDMS sheets. ASCs were differentiated into Schwann-like cells using a mixture of glial growth factors. Dorsal root ganglion (DRG) neurons were co-cultured with SCs and dASCs on PDMS/MWNTs sheets or non-coated dishes. An alamar blue proliferation assay of dASC and SCs showed significantly more dASC and SCs cultured on PDMS/MWNT sheets at 48 h and 72 h than when cultured on non-coated dishes (P < 0.05). Additionally, when DRG were cultured on PDMS/MWNT sheets seeded with dASCs, the proliferation of DRG neurons and the longest neurite outgrowth length per neuron were significantly greater than when DRG were cultured on PDMS/MWNT sheets alone or on non-coated dishes seeded with SCs or dASCs (P < 0.05). Overall, PDMS/MWNT sheets exhibited excellent biocompatibility for culturing Schwann-like cells differentiated from ASCs. Seeding the dASCs on PDMS/MWNT sheets may produce synergistic effects in peripheral nerve regeneration, similarly to SCs. This article is protected by copyright. All rights reserved. © 2015 Wiley Periodicals, Inc.
    Journal of Biomedical Materials Research Part A 04/2015; DOI:10.1002/jbm.a.35488 · 2.83 Impact Factor
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    ABSTRACT: Double stenting in a Y-configuration is a promising therapeutic option for wide-necked cerebral aneurysms not amenable to reconstruction with a single stent. We retrospectively evaluated the efficacy and safety of the crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms. By collecting clinical and radiological data we evaluated from January 2007 through December 2013, 20 wide-necked bifurcation aneurysms. Twelve unruptured and eight ruptured aneurysms in 20 patients were treated with crossing Y-stent-assisted coiling. Aneurysm size and neck size ranged from 3.2 to 28.2mm (mean 7.5mm) and from 1.9 to 9.1mm (mean 4.5mm). A Y-configuration was established successfully in all 20 patients. All aneurysms were treated with a pair of Neuroform stents. The immediate angiographic results were total occlusion in 17 aneurysms, residual neck in two, and residual sac in one. Peri-operative morbidity was only 5%. Fifteen of 18 surviving patients underwent follow-up conventional angiography (mean, 10.9 months). The result showed stable occlusion in all 15 aneurysms and asymptomatic in-stent occlusion in one branch artery. At the end of the observation period (mean, 33.5 months), all 12 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS 0), except one (mRS 2). Of eight patients with subarachnoid hemorrhage, four remained symptom free (mRS 0), while the other four had were dependent or dead (mRS score, 3-6). In this report on 20 patients, crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms showed a good technical safety and favorable clinical and angiographic outcome. Copyright © 2015. Published by Elsevier B.V.
    Clinical Neurology and Neurosurgery 03/2015; 132:54-60. DOI:10.1016/j.clineuro.2015.02.002 · 1.25 Impact Factor
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    ABSTRACT: For improving the drawbacks of previous thoracolumbar spine trauma classification, the Spine Trauma Study Group was developed new classification, Thoracolumbar Injury Classification and Severity Score (TLICS). The simplicity of this scoring system makes it useful clinical application. However, considering criteria of Korean Health Insurance Review and Assessment Service (HIRA), the usefulness of TLICS system is still controversial in the treatment decision of thoracolumbar spine injury. Total 100 patients, who admitted to our hospital due to acute traumatic thoracolumbar injury, were enrolled. In 45, surgical treatment was performed and surgical treatment was decided following the criteria of HIRA in all patients. With assessing of TLICS score and Denis's classification, the treatment guidelines of TLICS and Denis's classification were applied to the criteria of Korean HIRA. According to the Denis's three-column spine system, numbers of patients with 2 or 3 column injuries were 94. Only 45 of 94 patients (47.9%) with middle column injury fulfilled the criteria of HIRA. According to TLICS system, operation required fractures (score>4) were 31 and all patients except one fulfilled the criteria of HIRA. Conservative treatment required fractures (score<4) were 52 and borderline fracture (score=4) were 17. The TLICS system is very useful system for decision of surgical indication in acute traumatic thoracolumbar injury. However, the decision of treatment in TLICS score 4 should be carefully considered. Furthermore, definite criteria of posterior ligamentous complex (PLC) injury may be necessary because the differentiation of PLC injury between TLICS score 2 and 3 is very difficult.
    Journal of Korean Neurosurgical Society 03/2015; 57(3):174-7. DOI:10.3340/jkns.2015.57.3.174 · 0.52 Impact Factor
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    Kyoung Hyup Nam, Jae Il Lee, Byung Kwan Choi, In Ho Han
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    ABSTRACT: Spinal subarachnoid hemorrhages (SAH) can extend into the intracranial subarachnoid space, but, severe cerebral vasospasm is rare complication of the extension of intracranial SAH from a spinal subarachnoid hematoma. A 67-year-old woman started anticoagulant therapy for unstable angina. The next day, she developed severe back pain and paraplegia. MRI showed intradural and extramedullar low signal intensity at the T2-3, consistent with intradural hematoma. High signal intensity was also noted in the spinal cord from C5 to T4. We removed subarachnoid hematoma compressing the spinal cord. The following day, the patient complained of severe headache. Brain CT revealed SAH around both parietal lobes. Three days later, her consciousness decreased and left hemiplegia also developed. Brain MRI demonstrated multiple cerebral infarctions, mainly in the right posterior cerebral artery territory, left parietal lobe and right watershed area. Conventional cerebral angiography confirmed diffuse severe vasospasm of the cerebral arteries. After intensive care for a month, the patient was transferred to the rehabilitation department. After 6 months, neurologic deterioration improved partially. We speculate that surgeons should anticipate possible delayed neurological complications due to cerebral vasospasm if intracranial SAH is detected after spinal subarachnoid hematoma.
    Journal of Korean Neurosurgical Society 12/2014; 56(6):527-30. DOI:10.3340/jkns.2014.56.6.527 · 0.52 Impact Factor
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    ABSTRACT: Study Design. Prospective study of 25 patients who underwent anterior cervical surgery.Objective. To assess retraction pressure and the exposure of pharynx/esophagus (P/E) wall to the medial retractor blade to clarify whether medial retraction causes direct pressure transmission to the P/E wall.Summary of Background Data. Retraction pressure on P/E walls has been used to explain the relation between the retraction pressure and dysphagia or the efficacies of new retractor blades. However, it is doubtful whether the measured pressure represent real retraction pressure on the P/E wall because exposure of the P/E in the surgical field could be reduced by the shielding effect of thyroid cartilage.Methods. Epi- and endo-esophageal pressures were serially measured using online pressure transducers at 15minutes before retraction, immediately after retraction, and 30 minute after retraction. To measure the extent of P/E wall exposure to pressure transducer, we used posterior border of thyroid cartilage (PBTC) as a landmark. Intra-operative X-ray was used to mark the position of the posterior border of thyroid cartilage (PBTC). We checked out the marked location on retractors by measuring the distance from distal retractor tip.Results. The mean epi-esophageal pressure significantly increased after retraction (0 mmHg: 88.7±19.6 mmHg: 81.9±15.3 mmHg). The mean endo-esophageal pressure minimally changed after retraction (9.0±6.6 mmHg: 15.7±13.8 mmHg: 17.0±14.3 mmHg). The mean location of the posterior border of thyroid cartilage was 7.3±3.5mm on the retractor blade from the tip, which means epi-esophageal pressure was measured against the PBTC, not against the P/E wall.Conclusion. We suggest that a medial retraction blade does not transmit direct pressure on P/E wall due to minimal wall exposure and intervening thyroid cartilage. Our result should be considered when measuring retraction pressure during anterior cervical surgery or designing novel retractor systems.
    Spine 10/2014; 40(1). DOI:10.1097/BRS.0000000000000649 · 2.45 Impact Factor
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    ABSTRACT: Objective The purpose of this study was to investigate the incidence, cause, and influence of the adverse drug reactions (ADRs) associated with long-term intravenous antibiotics in patients with pyogenic spondylitis (PS). Methods We retrospectively reviewed the medical records of 84 patients with PS who underwent intravenous antibiotic therapy in our hospital from January 2001 to December 2012. ADRs were categorized to drug eruption, acute renal failure (ARF), hematologic toxicity, toxic hepatitis, pseudomembranous colitis (PMC), drug fever, and neuronal toxicity. Incidence and onset time of each ADR after antibiotic therapy were analyzed with the incidence of ADRs according to types of antibiotics. Results ADRs occurred in 38 of the 84 patients (incidence: 45.2%). The use of antibiotics was longer in the patients with ADRs (62.7 days) than in the patients without ADRs (44.3 day). The incidence of drug eruption, ARF, hematologic toxicity, toxic hepatitis, PMC, drug fever, and neuronal toxicity were 22.6, 11.9, 11.9, 10.7, 7.1, 3.6%, and 1.2%, respectively. The duration of antibiotics administration was related to the occurrence of PMC (p=0.001). ADRs were more common in patients treated by glycopeptides including vacomycin and teicoplanin. Conclusion The incidence of ADRs due to long-term intravenous antibiotics was as high as 45.2% in patients with PS. Therefore, we speculate that the possibility of delayed ADRs should be considered after long-term use of the antibiotics. Furthermore, close observation is mandatory to identify and treat ADRs promptly, even though PS revealed the improvement after antibiotic therapy.
    09/2014; 11(3):113-6. DOI:10.14245/kjs.2014.11.3.113
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    ABSTRACT: Artificial nerve guidance conduits (aNGCs) prepared from polymer scaffolds and carbon nanotubes (CNTs) possess unique chemical and physical properties, and have been widely used in preclinical trials to promote neuronal differentiation and growth. However, there have been only a few reports on the clinical applicability of CNT sheets for proliferation of primary neuronal cells due to safety concerns. The present study assesses the ability and potential applicability of multi-wall CNTs (MWNTs) composited with polydimethylsiloxane (PDMS) sheets to promote and enhance the proliferation of primary neuronal cells. In this study, the aqueous MWNT dispersion was filtered, and the PDMS/MWNT sheets were prepared using a simple printing transfer method. Characterization of PDMS/MWNT sheets demonstrated their unique physical properties such as superior mechanical strength and electroconductivity compared with PDMS sheets. The effect of the PDMS/MWNT sheets on the neural cell proliferation and cytotoxicity was evaluated using MTT and alamar blue assays. Our results indicate the viability and proliferation of primary neuronal cells and Schwann cells in PDMS/MWNT sheets increased over twice compared with a non-coated dish that is not usual in the primary neuronal cell growth control (p < 0.05). In addition, PDMS/MWNT sheets enhanced the adhesion and viability of the cells compared with poly-L-lysine coated dishes, which are most commonly used for improving cell adherence. Additionally, the PDMS/MWNT sheets exhibited excellent biocompatibility for culturing neuronal and Schwann cells. Overall, all assessments indicate that PDMS/MWNT sheets are ideal candidates for the development of artificial nerve conduits for clinical use following peripheral nerve injury.
    Journal of Biomedical Materials Research Part A 09/2014; 103(5). DOI:10.1002/jbm.a.35294 · 2.83 Impact Factor
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    ABSTRACT: Objectives Acupuncture is commonly used as a complimentary treatment for pain management. However, there has been no systematic review summarizing the current evidence concerning the effectiveness of acupuncture for acute postoperative pain after back surgery. This systematic review aimed at evaluating the effectiveness of acupuncture treatment for acute postoperative pain (≤1 week) after back surgery.Methods We searched 15 electronic databases without language restrictions. Two reviewers independently assessed studies for eligibility and extracted data, outcomes, and risk of bias. Random effect meta-analyses and subgroup analyses were performed.ResultsFive trials, including 3 of high quality, met our inclusion criteria. The meta-analysis showed positive results for acupuncture treatment of pain after surgery in terms of the visual analogue scale (VAS) for pain intensity 24 hours after surgery, when compared to sham acupuncture (standard mean difference −0.67 (−1.04 to −0.31), P = 0.0003), whereas the other meta-analysis did not show a positive effect of acupuncture on 24-hour opiate demands when compared to sham acupuncture (standard mean difference −0.23 (−0.58 to 0.13), P = 0.21).Conclusion Our systematic review finds encouraging but limited evidence for the effectiveness of acupuncture treatment for acute postoperative pain after back surgery. Further rigorously designed clinical trials are required.
    Pain Practice 04/2014; 15(3). DOI:10.1111/papr.12208 · 2.18 Impact Factor
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    ABSTRACT: Cerebrospinal fluid (CSF) diversion is an essential component of neurosurgical care, but the rates and significance of hemorrhage associated with external ventricular drainage (EVD) and ventriculoperitoneal (VP) shunt procedures have not been well quantified. In this retrospective study, the authors examined the frequencies of hemorrhagic complications associated with EVD and VP shunt procedures, and attempted to identify associated risk factors. The treatment records of 370 EVDs in 276 patients and 102 VP shunts in 96 patients performed between 2008 and 2010 were retrospectively reviewed. Post-insertion computed tomographic (CT) scans were analyzed for any new hemorrhage related to the ventricular catheter. The effects of diagnosis at admission, endovascular treatment, anti-platelet medication, and a concurrent craniotomy operation were included in the analysis conducted to identify risk factors of ventricular catheterrelated hemorrhage. Hemorrhage following EVD was detected on CT scans in 76 (20.5%) of the 370 cases. However, symptomatic hemorrhage occurred in only 5 cases (1.4% of all EVDs). VP shunt was associated with a higher incidence of ventricular catheter-related hemorrhage than EVD (hemorrhage rate: 43.1%) and the rate of detectable neurological change was 2.9%. Multivariate logistic-regression analysis of risk factors of EVD-related hemorrhage identified preoperative anti-platelet medication as the only significant factor (odds ratio, 3.583 [95% confidence interval, 1.353 to 9.486]; p = 0.010). Ventriculostomy-related hemorrhagic complications were more common than anticipated, especially for the VP shunt procedure. However, such hemorrhages are rarely large, rarely the cause of neurological deterioration, and rarely require surgical removal. Preoperative anti-platelet medication appears to affect EVD-related hemorrhage development.
    Neurologia medico-chirurgica 02/2014; 54(7). DOI:10.2176/nmc.oa.2013-0178 · 0.65 Impact Factor
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    ABSTRACT: A 47-year-old woman visited with lumbago and severe left leg pain that had been presented for 1 week. The patient complained of severe radiating pain on left L3 sensory dermatome area and reported aggravation of leg pain at 20 degrees of hip flexion by straight leg raising test (SLRT). However, there was no motor weakness on neurological examination. Magnetic resonance imaging (MRI) demonstrated contrast enhancing spinal extradural mass at L2-3 level that was iso-signal intensity (SI) on T1-weighted images (WI), hypo-SI on T2WI. She was not able to walk and sleep due to incapacitating pain. Thus, surgical removal was performed via left partial laminectomy. Postoperatively, the radiating pain was relieved completely. Histopathologic examination revealed that the tumor consisted of chondroma, which had mature hyaline cartilage with nests of benign-appearing cells and calcium deposits in lacunae.
    12/2013; 10(4):252-4. DOI:10.14245/kjs.2013.10.4.252
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    ABSTRACT: The purpose of this study is to evaluate the efficacy of laminoplasty in the treatment of spinal cord injury (SCI) without instability. 79 patients with SCI without instability who underwent surgical treatment in our institute between January 2005 and September 2012 were retrospectively reviewed. Twenty nine patients fulfilled the inclusion criteria as follows: SCI without instability, spinal cord contusion in MRI, cervical stenosis more than 20%, follow up at least 6 months. Preoperative neurological state, clinical outcome and neurological function was measured using the American Spinal Injury Association (ASIA) impairment scale, modified Japanese Orthopedic Association (mJOA) grading scale and Hirabayashi recovering rate. Seventeen patients showed improvement in ASIA grade and twenty six patients showed improvement in mJOA scale at 6 month follow up. However, all patients with ASIA grade B and C have shown improvement of one or more ASIA grade. Mean Hirabayashi recovery rate was 47.4±23.7%. There was better neurologic recovery in those who had cervical spondylosis without ossification of posterior longitudinal ligament (OPLL) (p<0.05, χ(2) test). It is different in B, C, D with ASIA A that there are debates going on about the application of surgical treatment in ASIA A, and surgical treatment is helpful in B, C, D since it contributes to neurologic improvement. We concluded that laminoplasty provided good neurologic recovery in SCI without instability that cervical canal stenosis, especially spondylosis without OPLL and neurologic deterioration in ASIA B, C and D.
    09/2013; 10(3):133-7. DOI:10.14245/kjs.2013.10.3.133
  • Kyoung Hyup Nam, In Ho Han, Won Ho Cho, Byung Kwan Choi
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    ABSTRACT: Lumbar intradural disc herniation (IDH) is rare, and intradural cyst associated with IDH is quite rare. Only seven cases of an intradural cyst associated with lumbar disc herniation have been reported, and all were gas-filled cysts. We report the first case, to our knowledge, of a fluid-filled intradural cyst associated with IDH. To report an extremely rare case of a fluid-filled intradural cyst associated with lumbar IDH and suggests the possible pathogenesis. Case report. An 82-year-old woman presented with right leg pain and motor weakness. Computed tomography and magnetic resonance imaging (MRI) scans showed calcified lumbar disc herniation and an intradural cystic mass at the L1-L2 level. An MRI, which was performed 2 years before admission, showed an IDH without a cyst at the same level. Surgical resection of the intradural cyst was performed. Intraoperative finding showed a fluid-filled intradural cyst with 1-cm diameter of displacing nerve rootlets. The cyst was connected with extradural cystic components through a ventral dural hole, but the tract was blocked by fibrous septum. Histopathologic examination showed a pseudocyst that consisted of degenerative cartilaginous and fibrous tissues, including degenerative disc materials. We concluded that the cyst was an intradural cyst transformed from the intradural disc fragment. The current case is the first report to our knowlege of a fluid-filled intradural cyst associated with IDH. The possible mechanism may be focal degeneration and spontaneous absorption of the intradural disc with fluid production. Unlike the gas-filled intradural cysts, the cause of the pure fluid-filled cyst may be disconnection from the intervertebral vacuum because of a calcified disc and septation of the cyst.
    The spine journal: official journal of the North American Spine Society 08/2013; 13(11). DOI:10.1016/j.spinee.2013.06.009 · 2.80 Impact Factor
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    ABSTRACT: The purposes of this study were to evaluate the prevalence, types, and locations of Modic changes (MCs) in the thoracic spine in a large number of subjects, and to investigate the relation between the distributions of MCs and disc herniations (DHs) in the thoracic spine. Two experienced musculoskeletal radiologists assessed the presence of MCs and DHs by consensus in the thoracic MRIs of 144 patients with non-specific back pain. Patient ages ranged from 22 to 88 years (mean=53.3±14.66 years), and 72 were female (50%). The prevalence, distribution, relation of MCs and DHs was recorded. MC was observed in 8 of the 144 patients (5.6%) and 10 of 1728 segments (0.58%). The most common MC was type II. Of the 8 patients exhibiting MC, 6 had type II (75.0%), and 2 had mixed MCs (type I/II or type II/III). MCs were distributed mainly at the mid-thoracic level (from T5/6 to T9/10). DH was detected in 18 patients (12.5%), 36 of 1728 segments (2.1%). Of the 10 segments exhibiting MC, 5 had DHs at the same level (50.0%). Accordingly, DH was strongly associated with MC (p=0.000). A low prevalence of MC was observed in the thoracic spine, and type II MC predominated. The low prevalence of MC in the thoracic spine suggests that it was caused by a relative lack of mobility as compared with the cervical and lumbar spines. And DHs were found to be strongly associated with MCs even in the thoracic spine.
    Journal of Korean Neurosurgical Society 07/2013; 54(1):34-7. DOI:10.3340/jkns.2013.54.1.34 · 0.52 Impact Factor
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    ABSTRACT: Ginsenoside is known to have potential cancer-preventive activities. The major active components in red ginseng consist of a variety of ginsenosides including Rg3, Rg5 and Rk1, each of which has different pharmacological activities. Among these, Rg3 has been reported to exert anticancer activities through inhibition of angiogenesis and cell proliferation. However, the effects of Rg3 and its molecular mechanism on glioblastoma multiforme (GBM) remain unclear. Therefore, it is essential to develop a greater understanding of this novel compound. In the present study, we investigated the effects of Rg3 on a human glioblastoma cell line and its molecular signaling mechanism. The mechanisms of apoptosis by ginsenoside Rg3 were related with the MEK signaling pathway and reactive oxygen species. Our data suggest that ginsenoside Rg3 is a novel agent for the chemotherapy of GBM.
    Oncology Reports 06/2013; 30(3). DOI:10.3892/or.2013.2555 · 2.19 Impact Factor
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    Hwa Joong Lee, Won Ho Cho, In Ho Han, Byung Kwan Choi
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    ABSTRACT: The standard treatment for symptomatic spinal extradural arachnoid cyst (SEAC) is complete surgical removal of cyst and closure of the dural defect. In most cases, total laminectomy has been performed at affected vertebra for complete removal of the SEAC. However, this invasive surgery may result in postoperative kyphosis and back pain. We report a case of large SEAC involving T10-L1 which was excised through the minimal skipped hemilaminectomy, to minimize the risk of postoperative kyphotic deformity. Simultaneously, we closed the dural defect after preoperative precise identification of the site through several radiological studies.
    03/2013; 10(1):28-31. DOI:10.14245/kjs.2013.10.1.28
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    ABSTRACT: The Leksell Gamma Knife® (LGK) is based on a single-fraction high dose treatment strategy. Therefore, independent verification of the Leksell GammaPlan® (LGP) is important for ensuring patient safety and minimizing the risk of treatment errors. Although several verification techniques have been previously developed and reported, no method has ever been tested statistically on multiple LGK target treatments. The purpose of this study was to perform and to evaluate the accuracy of a verification method (modified variable ellipsoid modeling technique, MVEMT) for multiple target treatments. A total of 500 locations in 10 consecutive patients with multiple brain tumor targets were included in this study. We compared the data from an LGP planning system and MVEMT in terms of dose at random points, maximal dose points, and target volumes. All data was analyzed by t-test and the Bland-Altman plot, which are statistical methods used to compare two different measurement techniques. No statistical difference in dose at the 500 random points was observed between LGP and MVEMT. Differences in maximal dose ranged from -2.4% to 6.1%. An average distance of 1.6 mm between the maximal dose points was observed when comparing the two methods. Statistical analyses demonstrated that MVEMT was in excellent agreement with LGP when planning for radiosurgery involving multiple target treatments. MVEMT is a useful, independent tool for planning multiple target treatment that provides statistically identical data to that produced by LGP. Findings from the present study indicate that MVEMT can be used as a reference dose verification system for multiple tumors.
    Journal of Korean Neurosurgical Society 02/2013; 53(2):102-7. DOI:10.3340/jkns.2013.53.2.102 · 0.52 Impact Factor
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    ABSTRACT: Study Design. A case report of anaerobic vertebral osteomyelitis after percutaneous epidural adhesiolysis.Objective. To present a case of Bacteroides fragilis spondylodiscitis (BFS) secondary to percutaneous epidural adhesiolysis in 38-year-old woman without predisposing factors.Summary of Background Data. Most cases of BFS result from hematogenous spread from a perianal abscess or sigmoidoscopy or local spread from an adjacent infection. However, BFS due to direct inoculation after percutaneous epidural adhesiolysis has not been previously reported.Methods. A 38-year-old woman presented with spondylodiscitis at the L4-5 level 2 weeks after percutaneous epidural adhesiolysis. Despite empirical antibiotherapy, the spondylodiscitis and an epidural abscess became much aggravated. Open biopsy and curettage was performed, and metronidazole sensitive Bacteroides fragilis was identified by tissue culture.Results. Metronidazole was administrated for 5 weeks and symptoms were completely resolved. Follow-up MRI showed that the spondylodiscitis was completely cured.Conclusion. This is the first report to be issued regarding BFS secondary to percutaneous epidural adhesiolysis. In our case, the pathogenesis may have been direct inoculation of Bacteroides fragilis into the epidural space and disc during percutaneous epidural adhesiolysis because the procedural approach used was adjacent to the anus.
    Spine 01/2013; DOI:10.1097/BRS.0b013e31828671f9 · 2.45 Impact Factor
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    ABSTRACT: Coding Systematized Nomenclature of Medicine, Clinical Terms (SNOMED CT) with complex and polysemy clinical terms may ask coder to have a high level of knowledge of clinical domains, but with simpler clinical terms, coding may require only simpler knowledge. However, there are few studies quantitatively showing the relation between domain knowledge and coding ability. So, we tried to show the relationship between those two areas. We extracted diagnosis and operation names from electronic medical records of a university hospital for 500 ophthalmology and 500 neurosurgery patients. The coding process involved one ophthalmologist, one neurosurgeon, and one medical record technician who had no experience of SNOMED coding, without limitation to accessing of data for coding. The coding results and domain knowledge were compared. 705 and 576 diagnoses, and 500 and 629 operation names from ophthalmology and neurosurgery, were enrolled, respectively. The physicians showed higher performance in coding than in MRT for all domains; all specialist physicians showed the highest performance in domains of their own departments. All three coders showed statistically better coding rates in diagnosis than in operation names (p < 0.001). Performance of SNOMED coding with clinical terms is strongly related to the knowledge level of the domain and the complexity of the clinical terms. Physicians who generate clinical data can be the best potential candidates as excellent coders from the aspect of coding performance.
    09/2012; 18(3):186-90. DOI:10.4258/hir.2012.18.3.186
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    ABSTRACT: The purpose of this study was to present the MRI and CT findings of solitary spinal bone lesions (SSBLs) with the aims of aiding the differential diagnoses of malignant tumors and benign lesions, and proposing a diagnostic strategy for obscure SSBLs. The authors retrospectively reviewed the imaging findings of 19 patients with an obscure SSBL on MRI at our hospital from January 1994 to April 2011. The 19 patients were divided to benign groups and malignant groups according to final diagnosis. MRI and CT findings were evaluated and the results of additional work-up studies were conducted to achieve a differential diagnosis. At final diagnoses, 10 (52.6%) of the 19 SSBLs were malignant tumors and 9 (47.4%) were benign lesions. The malignant tumors included 6 metastatic cancers, 3 multiple myelomas, and 1 chordoma, and the benign lesions included 4 osteomyelitis, 2 hemangiomas, 2 nonspecific chronic inflammations, and 1 giant cell tumor. No MRI characteristics examined was found to be significantly different in the benign and malignant groups. Reactive sclerotic change was observed by CT in 1 (10.0%) of the 10 malignant lesions and in 7 (77.8%) of the 9 benign lesions (p=0.005). Approximately half of the obscure SSBLs were malignant tumors. CT and MRI findings in combination may aid the differential diagnosis of obscure SSBLs. In particular, sclerotic change on CT images was an important finding implying benign lesion. Finally, we suggest a possible diagnostic strategy for obscure SSBLs on MRI.
    Journal of Korean Neurosurgical Society 08/2012; 52(2):126-32. DOI:10.3340/jkns.2012.52.2.126 · 0.60 Impact Factor