• Investigative Magnetic Resonance Imaging
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• v.23 no.2
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• pp.114-124
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• 2019

Purpose: We investigate biases in the assessments of left ventricular function (LVF), by compressed sensing (CS)-cine magnetic resonance imaging (MRI). Materials and Methods: Cardiovascular cine images with short axis view, were obtained for 8 volunteers without CS. LVFs were assessed with subsampled data, with compression factors (CF) of 2, 3, 4, and 8. A semi-automatic segmentation program was used, for the assessment. The assessments by 3 CS methods (ITSC, FOCUSS, and view sharing (VS)), were compared to those without CS. Bland-Altman analysis and paired t-test were used, for comparison. In addition, real-time CS-cine imaging was also performed, with CF of 2, 3, 4, and 8 for the same volunteers. Assessments of LVF were similarly made, for CS data. A fixed compensation technique is suggested, to reduce the bias. Results: The assessment of LVF by CS-cine, includes bias and random noise. Bias appeared much larger than random noise. Median of end-diastolic volume (EDV) with CS-cine (ITSC or FOCUSS) appeared -1.4% to -7.1% smaller, compared to that of standard cine, depending on CF from (2 to 8). End-systolic volume (ESV) appeared +1.6% to +14.3% larger, stroke volume (SV), -2.4% to -16.4% smaller, and ejection fraction (EF), -1.1% to -9.2% smaller, with P < 0.05. Bias was reduced from -5.6% to -1.8% for EF, by compensation applied to real-time CS-cine (CF = 8). Conclusion: Loss of temporal resolution by adopting missing data from nearby cardiac frames, causes an underestimation for EDV, and an overestimation for ESV, resulting in underestimations for SV and EF. The bias is not random. Thus it should be removed or reduced for better diagnosis. A fixed compensation is suggested, to reduce bias in the assessment of LVF.

• Journal of Korean Society on Water Environment
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• v.35 no.1
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• pp.9-18
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• 2019

Recently, it was realized that a significant portion of pollution from urban areas originates from non-point sources such as construction sites, washoff from impervious surfaces, and sewage input from unsewered areas and combined sewer overflows. Especially, Urban stormwater runoff is one of the most extensive cause of the deterioration of the water quality in streams located in urban area. The objective of this study was to investigate runoff characteristics of non-point pollutants source at the urban area in the Suyeong River. Water quality variations were investigated at two points of Suyeong River during a period of 10 rainfall events. Concentration difference of non-point pollution source appeared big by precedent number of days of no rainfall. In addition, Event mean Concentration (EMCs) that well represents runoff characteristics of storm water during rainfall, was calculated, and runoff pollutants loading was also examined. The probability distribution of EMCs of BOD, COD, TOC, T-N, T-P, and TSS were analyzed and the mean values of observed EMC and the median values of estimated EMCs compared through probability distribution. Other objectives of this study were the characterization of discharge from non-point source, the analysis of the pollutant loads and an establishment of a management plan for non-point source of Suyeong River. Also, It was established that the most important thing for the administration of non-point pollution source is to come up with the solution for the reduction of effluent at the beginning.

• BLOOD RESEARCH
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• v.53 no.4
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• pp.307-313
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• 2018

Background Primary ocular adnexal extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (POML) is the most common subtype of lymphoma involving the eyes in Thailand. We sought to assess the characteristics and treatment outcomes of patients with POML in Thailand. Methods We retrospectively reviewed patient data and included patients diagnosed with POML between January 2004 and December 2016 at Chiang Mai University Hospital and King Chulalongkorn Memorial Hospital, Thailand. We collected and analyzed patients' clinical characteristics and treatment outcomes. Results Among 146 patients with lymphoma involving the eyes, 121 (82%) were diagnosed with POML. Sixty-four (52.9%) were women with median age 58 (range, 22-86) years. The most common presenting symptom was orbital mass (71.1%). Common sites of origin were the orbit (46.3%) and lacrimal gland (34.7%). At presentation, 22.3% of patients had bilateral eye involvement. About half of patients had stage I disease (N=59, 56.2%) and 20% had stage IV. Most patients (73.3%) had a low-risk International Prognostic Index. Radiotherapy was the main treatment for patients with limited-stage disease (66.7% in stage I and 56.5% in stage II). The overall response rate was 100% with complete response rates 80%, 77.3%, and 64.7% for stages I, II, and IV, respectively. Five-year progression-free survival (PFS) and overall survival were 66.1% and 94.0%, respectively. For patients with limited-stage disease, radiotherapy significantly improved PFS compared with treatment not involving radiotherapy (5-year PFS 89.9% vs. 37.3%, P=0.01). Conclusion We revealed that POML has good response to treatment, especially radiotherapy, with excellent long-term outcome.

• Yonsei Medical Journal
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• v.59 no.9
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• pp.1049-1056
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• 2018

Purpose: Local recurrence is the most common cause of failure in retroperitoneal soft tissue sarcoma patients after surgical resection. Postoperative radiotherapy (PORT) is infrequently used due to its high complication risk. We investigated the efficacy of PORT using modern techniques in patients with retroperitoneal soft tissue sarcoma. Materials and Methods: Eighty patients, who underwent surgical resection for non-metastatic primary retroperitoneal soft tissue sarcoma at the Yonsei Cancer Center between 1994 and 2015, were retrospectively reviewed. Thirty-eight (47.5%) patients received PORT: three-dimensional conformal radiotherapy in 29 and intensity-modulated radiotherapy in nine patients. Local failure-free survival (LFFS), overall survival (OS), and RT-related toxicities were investigated. Results: Median follow-up was 37.1 months (range, 5.8-207.9). Treatment failure occurred in 47 (58.8%) patients including local recurrence in 33 (41.3%), distant metastasis in eight (10%), and both occurred in six (7.5%) patients. The 2-year and 5-year LFFS rates were 63.9% and 47.9%, respectively. The 2-year and 5-year OS rates were 87.5% and 71.1%. The 5-year LFFS rate was significantly higher in PORT group than in no-PORT group (74.2% vs. 24.3%, p<0.001). In multivariate analysis, PORT was the only independent prognostic factor for LFFS. However, there was no significant correlation between RT dose and LFFS. OS showed no significant difference between the two groups. Grade ${\leq}2$ acute toxicities were observed in 63% of patients, but no acute toxicity ${\geq}$ grade 3 was observed. Conclusion: PORT using modern technique markedly reduced local recurrence in retroperitoneal sarcoma patients, with low toxicity. The optimal RT technique, in terms of RT dose and target volume, should be further investigated.

• Journal of Korean Neurosurgical Society
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• v.64 no.1
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• pp.39-50
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• 2021

Objective : The treatment of large aneurysms of the posterior circulation is complicated and remains challenging. We here analyzed our institutional clinical outcomes of large unruptured aneurysms of the posterior circulation. Methods : This study included 56 patients who presented with a large (>10 mm) unruptured aneurysm of the posterior circulation between 2002 and 2018. Results : There were 18 (32.1%) male and 38 (67.9%) female patients, with a mean age of 53.4 years. The most common location was the vertebral artery, followed by the basilar tip and posterior cerebral artery. The median follow-up duration was 29 months. Eighteen patients (32.1%) were treated by transcranial surgery and 38 (67.9%) were treated by endovascular treatment (EVT). Post-treatment complications occurred in 16 patients (28.6%), with there being no significant difference between the transcranial surgery and EVT groups. Complete obliteration was achieved in 30 patients (53.6%), with there being no statistically significant difference between the transcranial surgery and EVT groups. Recurrence occurred in 17 patients (30.4%), and the rate of recurrence was higher in the EVT group than in the transcranial surgery group (39.5% vs. 11.1%, p=0.03). Forty-four (84%) of 56 patients showed a favorable functional outcome. In saccular aneurysm, EVT was negative predictor of worsening of functional status. Conclusion : Treatment of these aneurysms harbors an inherent high risk of morbidity. No superiority was found between transcranial surgery and EVT in terms of complications and complete obliteration, but transcranial surgery showed a higher treatment durability than EVT.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.619-630
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• 2021

Objective : The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS. Methods : A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled. We retrospectively reviewed the medical and radiological records to analyze the preoperative features and postoperative results. Results : The diagnoses included craniopharyngioma (46.8%), meningioma (34.0%), pituitary adenoma (5.3%), chordoma (1.6%), Rathke's cleft cyst (1.1%) and others (n=21, 11.2%). The trans-planum/tuberculum approach (94.3%) was the most commonly adapted surgical method, followed by the trans-sellar and transclival approaches. The third ventricle was opened in 78 patients (41.5%). Lumbar CSF drainage was not performed postoperatively in any of the patients. Postoperative CSF leakage occurred in four patients (1.7%) due to technical mistakes and were repaired with the same technique. However, postoperative meningitis occurred in 13.5% (n=31) of the patients, but no microorganisms were identified. The median latency to the diagnosis of meningitis was 8 days (range, 2-38). CSF leakage was the unique risk factor for postoperative meningitis (p<0.001). Conclusion : The use of multiple onlay grafts with FSP, HAC, and PNF is a reliable reconstruction technique that provides immediate and complete CSF leakage repair and mucosal grafting on the skull base without the need to harvest autologous tissue or perform postoperative CSF diversion. However, postoperative meningitis should be monitored carefully.

• Obstetrics & gynecology science
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• v.61 no.6
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• pp.649-654
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• 2018

Objective Isotretinoin is a notorious teratogen otherwise used for the treatment of acne vulgaris. Some countries, including those in North America and the European Union, implemented the pregnancy prevention program (PPP); however, no PPP has yet been established in South Korea. So the aim of this study was to evaluate the rate of pregnant women exposed to isotretinoin among the callers of the Korean Mother Safe Counseling Center. Methods This is a prospective cohort study. We evaluated the demographic characteristics, obstetric history, and isotretinoin exposure of pregnant women based on the mother safe registry from April 2010 to July 2016. Results Among 22,374 callers, 650 (2.9%) pregnant women were exposed to isotretinoin. The mean age was $29.0{\pm}4.4$ years in the isotretinoin-exposed group and $32.0{\pm}4.2$ years in the unexposed group (P<0.001). Moreover, the incidence of pregnancies within 30 days after isotretinoin discontinuation or during isotretinoin intake was 78.9% (513/650). The median duration of isotretinoin exposure was 18 (1-4,231) days. Furthermore, from 2011 to 2015, the incidence of isotretinoin exposure was $2.9{\pm}1.2$ pregnancies per 10,000 births in South Korea. Conclusion Approximately 80% of pregnant women are exposed to isotretinoin within the recommended 30 days of contraception or during pregnancy. Therefore, the PPP has to be established in South Korea.

• Journal of Pharmacopuncture
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• v.24 no.2
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• pp.84-90
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• 2021

Objectives: Our study aimed to determine the attitudes of second- and final-year medical students and doctors (teaching faculty) of modern medicine towards complementary and alternative medicine (CAM) using the Complementary, Alternative, and Integrative Medicine Attitude Questionnaire (CAIMAQ). Methods: We invited 248 second-year medical students, 245 final-year medical students, and 48 faculty members to participate in the study. The CAIMAQ consists of 30 items, divided into five categories assessing various aspects of CAM, and scored using a 7-point Likert scale. The median scores obtained were compared between groups; a p-value < 0.05 was considered statistically significant. Results: A total of 138 medical students and faculty responded and participated in the study, of which, 24 (17.4%) were faculty, 40 (29%) were final-year medical students and 74 (53.6%) were second-year medical students. The overall attitude towards the various CAM concepts and therapies was positive. In general, the faculty were significantly less likely to consider referring patients for CAIM treatments, integrating them with conventional medicine, referring patients to alternative healthcare providers, considering the use of subtle energy fields as an ethical form of treatment, or considering CAIM treatments to be less invasive and harmful compared with conventional medicine. There was no significant difference in the attitudes of second- and final-year students. Conclusion: The attitude of medical students and doctors towards CAM is positive, and although the medical faculty have reservations in recommending specific types of CAM therapies or integrating them with conventional care, building evidence for supporting CAM therapies in specific diseases is likely to increase its uptake among health care professionals.

• The Korean Journal of Pain
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• v.34 no.3
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• pp.315-321
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• 2021

Background: Pillar pain may develop after carpal tunnel release surgery (CTRS). This prospective double-blinded randomized trial investigated the effectiveness of extracorporeal shock wave therapy (ESWT) in pillar pain relief and hand function improvement. Methods: The sample consisted of 60 patients with post-CTRS pillar pain, randomized into two groups. The ESWT group (experimental) received three sessions of ESWT, while the control group received three sessions of sham ESWT, one session per week. Participants were evaluated before treatment, and three weeks, three months, and six months after treatment. The pain was assessed using the visual analogue scale (VAS). Hand functions were assessed using the Michigan hand outcomes questionnaire (MHQ). Results: The ESWT group showed significant improvement in VAS and MHQ scores after treatment at all time points compared to the control group (P < 0.001). Before treatment, the ESWT and control groups had a VAS score of 6.8 ± 1.3 and 6.7 ± 1.0, respectively. Three weeks after treatment, they had a VAS score of 2.8 ± 1.1 and 6.1 ± 1.0, respectively. Six months after treatment, the VAS score was reduced to 1.9 ± 0.9 and 5.1 ± 1.0, respectively. The ESWT group had a MHQ score of 54.4 ± 7.7 before treatment and 73.3 ± 6.8 six months after. The control group had a MHQ score of 54.2 ± 7.1 before treatment and 57.8 ± 4.4 six months after. Conclusions: ESWT is an effective and a safe non-invasive treatment option for pain management and hand functionality in pillar pain.

• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.320-329
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• 2021

Background: Smoking exposure may be objectively assessed through specific biomarkers. The most common biomarker for smoking is cotinine concentration in urine, and setting an optimal cut-off point can accurately classify smoking status. Such a cut-off point for Korean adolescents has never been studied. Objectives: The aim of this study was to determine a cut-off point for urinary cotinine concentration for the discrimination of smoking in adolescents. Methods: Participants were adolescents aged 13~18 years who participated in the third cycle of the Korean National Environmental Health Survey. We used urine samples to confirm the level of cotinine concentrations. Smoking status was determined by self-reported questionnaire. We identified the optimal cotinine cut-off point for discriminating smoking status using receiver operating characteristic curve analysis. Results: Of the 904 participants, 28 (3.1%) were smokers, among whom 20 (71.4%) were male. The median urinary cotinine concentrations in smokers was 218 ㎍/L (male: 215 ㎍/L, female: 303 ㎍/L), and that in non-smokers was 1.31 ㎍/L (male: 1.46 ㎍/L, female: 1.18 ㎍/L). We found significant differences in urinary cotinine concentration according to smoking status and sex (p<0.001). Urinary cotinine concentrations performed well for identifying smoking adolescents [area under the curve: 0.954 (male: 0.963, female: 0.908)]. The cut-off that optimally distinguished smokers from non-smokers was 39.85 ㎍/L (sensitivity: 89.3%, specificity: 97.4%). Male [39.85 ㎍/L (sensitivity: 90.0%, specificity: 94.9%)] had a different optimal cut-off point than female [26.26 ㎍/L (sensitivity: 87.5%, specificity: 99.6%)]. Conclusions: This study determined a cut-off point for urinary cotinine of 39.85 ㎍/L (male: 39.85 ㎍/L, female: 26.26 ㎍/L) to distinguish smokers from non-smokers in adolescents.