Publications by authors named "Seong-Chan Kim"

Article Synopsis
  • The study investigates how the distance between the laser fiber tip and soft tissue affects the destruction of that tissue during holmium laser enucleation of the prostate (HoLEP).
  • By experimenting with a soft tissue phantom at various distances, the researchers evaluated the effects of laser pulses on tissue destruction and thermal impact.
  • Results show that as the distance increases, the laser's ability to destroy tissue decreases, but thermal effects can still be significant even at greater distances.
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  • The study focused on improving shockwave lithotripsy, a treatment for kidney stones, by considering how breathing affects targeting and safety.
  • They used a device to mimic kidney movement during breathing and tested artificial stones in a gel, measuring changes after shockwave exposure, along with clinical trials on patients wearing respiratory masks.
  • Results showed better treatment efficiency with regular breathing patterns, a 65.6% success rate in regular breathers compared to 40% in irregular breathers, suggesting that managing breathing can enhance the lithotripsy process and reduce patient discomfort.
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This study aims to verify if the beating sound of a singing bowl synchronizes and activates brain waves during listening. The singing bowl used in this experiment produce beats at a frequency of 6.68 Hz, while it decays exponentially and lasts for about 50 s.

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Article Synopsis
  • - A polyacrylamide polysaccharide hydrogel (PASG) with a nonionic surfactant (NP14) has been developed to create a cost-effective and reusable tissue-mimicking phantom for visualizing thermal lesions during high intensity focused ultrasound (HIFU) treatment.
  • - This hydrogel is transparent at room temperature but becomes opaque white at temperatures above 55 °C, allowing for easy visualization of changes when heated and cooled.
  • - The acoustic properties of the NP14-PASG mimic those of human liver tissue, making it suitable for evaluating HIFU devices, and it has the potential to replace more expensive options currently used for testing.
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Background: It is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage.

Methods: A total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1 J-10 Hz, 1 J-20 Hz, 1 J-30 Hz, and 2 J-10 Hz.

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Shock waves are commonly used in the field of urology. They have two phases, positive and negative, and the bubble generation is roughly classified into acoustic cavitation (AC) and laser-induced cavitation (LIC). We evaluated the occurrence of cavitation, its duration, the area of interest, and the maximal diameter of the cavitation bubbles.

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Due to the ongoing COVID-19 pandemic situation, measures to mitigate the risk of transmission of the SARS-CoV-2 virus in an indoor setting are urgently needed. Among the various types of disinfectant methods, electrostatic spraying is often applied to decontamination in public places. For quantitatively characterizing electrostatic spraying, we developed the novel evaluation method by using a fluorescent tracer.

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Background: Opening-wedge high tibial osteotomy produces opening gaps; however, there is little consensus on bone graft necessity and the material that would produce a superior union. The purposes of the present study were (1) to compare the serial union patterns associated with various bone-void fillers, (2) to determine whether bone-void filler is necessary to achieve bone union of the opening gap, and (3) to determine whether bone union is different according to the correction degree during opening-wedge high tibial osteotomy.

Methods: In this retrospective study, 97 knees were randomly assigned to treatment with hydroxyapatite chip bone (Group A), allogenic chip bone (Group B), or no bone graft (Group C) and were analyzed after a minimum 1-year follow-up.

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Background: The aims of this study were to evaluate the effects of correcting lower limb alignment by total knee arthroplasty (TKA) on the spinopelvic alignment and to identify patients with difference in the knee joint between clinically measured passive motion and the actual standing posture.

Methods: In this retrospective study, 101 patients who underwent TKA and whose serial whole-body EOS X-ray were available were included. The relationship of the knee and spinopelvic alignment was analyzed by evaluating the parameters of standing anterior-posterior and lateral whole-body EOS X-ray.

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The purposes of this study were (1) to evaluate the relationship between lumbosacral flexibility and the effects of total knee arthroplasty (TKA) on whole-body alignment; and (2) to determine the prerequisites of the adjacent joints for successful TKA. A total of 116 patients (156 cases) who had whole-body X-ray and flexion-extension lumbar radiograph available were enrolled. For the sagittal alignment evaluation, hip-knee-ankle (HKA) angle, pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), and C7 plumb line-sacrum distance (SVA) were evaluated on the whole-body radiographs.

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Background: The purposes of this study were to evaluate whether the planning method using the contralateral limb status is reasonable and to determine the disparity between the preoperative planning and actual postoperative correction status by analyzing lateral cortical hinge fractures (LCHFs) in patients who underwent distal femoral osteotomy (DFO).

Methods: From 2014 to 2018, 31 cases undergoing DFO were evaluated. The patients were divided into two groups according to two preoperative planning methods.

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This study aims to evaluate the filtration performance of three commercially available (3M 8210 respirator, Halyard 48207 surgical mask, and 3M 1820 procedure mask) and two alternative face mask and respirator materials (Halyard H600 sterilization wrap and Cummins EX101) after selected decontamination treatments, including isopropanol (IPA) treatments (soaking or spraying), ultraviolet germicidal irradiation (UVGI), and heat treatments (dry heat at 77 °C or steam heat). Both IPA soaking and spraying removed most electrostatic charges on all four electret materials (three commercial and one alternative), causing significant deterioration of filtration efficiency to unacceptable level. The other non-electret alternative material sustained its N95-grade performance after both IPA soaking and spraying treatments, demonstrating the possible application of IPA disinfection for non-electret alternative respirator/mask materials.

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Background: Early osteoarthritis of the knee joint mostly affects the medial compartment, making osteotomy a rational approach to slow the progression of the disease. However, some patients show asymptomatic mild degeneration in the lateral or patellofemoral compartment.

Purpose: To evaluate the effect of asymptomatic mild lateral or patellofemoral degeneration on the outcomes of medial open wedge high tibial osteotomy (OWHTO) by assessing the outcomes according to the preoperative status of the lateral or patellofemoral degenerative changes.

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Background: The aims of this study were to (1) describe our functional stepwise multiple needle puncturing (MNP) technique as the final step in medial ligament balancing during total knee arthroplasty (TKA) and (2) evaluate whether this technique can provide sufficient medial release with safety.

Methods: A total of 137 patients with 212 consecutive knees who underwent TKAs with or without functional stepwise MNP of superficial medial collateral ligament was recruited in this prospective cohort. Eighty-one patients with 129 knees who performed serial stress radiographs were enrolled in the final assessment.

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Background: This study aimed at assessing the morphometry of resected femurs in Korean patients during total knee arthroplasty (TKA) and comparing these measurements with current Western-designed femoral component dimensions.

Methods: This single-blind, prospective, randomized, controlled trial involved intraoperative measurements for 271 femoral component implantations from 3 contemporary TKA systems, with 2 systems offering narrow sizing options. The difference between femoral component dimensions and the resected surface of distal femur was measured in millimeters at 5 distinct zones.

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Background: Water pressure and muscle contraction may influence bone mineral density (BMD) in a positive way. However, divers experience weightlessness, which has a negative effect on BMD. The present study investigated BMD difference in normal controls and woman free-divers with vertebral fracture and with no fracture.

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Purpose: The modified Yale Preoperative Anxiety Scale (mYPAS) was developed for evaluating the level of preoperative anxiety in children. The purpose of this study was to develop a Korean version of the mYPAS (K-mYPAS) and to establish its validity and reliability based on the Korean preoperative pediatric patients.

Methods: K-mYPAS was made through stringent back-translation procedure.

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Brain cortico-striatal circuits have consistently been implicated in the pathology of addiction related disorders. We applied a reliable seed-based analysis of the resting-state brain activity to comprehensively delineate the subdivisions of striatal functional connectivity implicated in internet gaming disorder. Among twelve right-handed male adolescents with internet gaming disorder and 11 right-handed and gender-matched healthy controls, we examined group differences in the functional connectivity of dorsal and ventral subdivisions of the caudate nucleus and putamen, as well as the association of these connectivity indices with behavioral measures of internet use.

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Genes associated with circadian rhythms have been suggested to play an important role in the pathophysiology of bipolar disorder. A single nucleotide polymorphism (SNP) in the 3'-flanking region of CLOCK (3111T/C; rs1801260) has been reported to be associated with sleep disturbances and an increased recurrence rate in patients with bipolar disorder. We examined the association of CLOCK 3111T/C with bipolar disorder in 260 patients and 350 controls in a Korean population.

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Objectives: Although a broad range of circadian rhythm variations have been reported, analyses of chronotypes in bipolar I disorder (BDI) and schizophrenia are rare. The present study aimed to investigate specific chronotype patterns in BDI and schizophrenia compared with healthy subjects.

Methods: All patients were clinically stable and recruited from the outpatient clinics of Seoul National University Hospital.

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Recent studies have suggested the involvement of Glycogen synthase kinase-3 beta (GSK-3 beta) in pathogenesis and treatment target of schizophrenia and bipolar disorder, which led to consider GSK-3 beta as one of the candidate genes for those disorders. However, the association analysis between GSK-3 beta and either schizophrenia or bipolar disorder is yet to be reported in Korean population. Along with 350 healthy individuals, a sample of 138 schizophrenia and 120 bipolar patients was analyzed for two common SNPs at position -1727 A/T and -50 C/T polymorphism localized in intron 1 of the gene.

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The present study aimed to elucidate the effectiveness of clozapine treatment in reducing the disabling period of chronically ill schizophrenic patients by investigating their rehospitalization status. Of 232 schizophrenic patients with a history of clozapine use who were recruited from the clinic at Seoul National University Hospital, 117 were selected who had been followed up for more than 1 year with respect to rehospitalization. To obtain information about the period before the clozapine change, a chart review of these 117 patients was conducted.

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The Liverpool University Neuroleptic Side-Effect Rating Scale (LUNSERS) was examined for its usefulness as a subjective measure of drug-induced parkinsonism and akathisia. Eighty-three subjects were assessed using the LUNSERS, the Simpson-Angus Scale (SAS) and the Barnes Akathisia Rating Scale (BARS), before and after a 6-week treatment with olanzapine. Significant correlations were found between the changes in scores of parkinsonism items of LUNSERS and SAS.

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