• Journal of the Korean Society of Radiology
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• v.6 no.5
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• pp.365-371
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• 2012

The radiation therapy treatment technique is developed from 3D-CRT, IMRT to Tomotherapy. and these three technique was most widely using methods. We find out a comparison normal tissue doses and tumor dose of 3D-CRT, IMRT(Linac Based), and Tomotherapy on Head and Neck Cancer. We achieved radiological image used the Human model phantom (Anthropomorphic Phantom) and it was taken CT simulation (Slice Thickness : 3mm) and GTV was nasopharngeal region and PTV(including set-up margin) was GTV plus 2mm area. and transfer those images to the radiation planning system (3D-CRT - ADAC-Pinnacle3, Tomotherapy - Tomotherapy Hi-Art System). The prescription dose was 7020 cGy and measuring PTV's dose and nomal tissue (parotid gland, oral cavity, spinal cord). The PTV's doses was Tomotherapy, Linac Based - IMRT, 3D-CRT was 6923 cGy, 6901 cGy and 6718 cGy its dose value was meet TCP because its value was up to the 95% based on 7020 cGy, Nomal tissue (parotid gland, oral cavity, spinal cord) was 1966 cGy(Tomotherapy), 2405 cGy(IMRT), 2468 cGy(3D-CRT)[parotid gland], 2991 cGy(Tomotherapy), 3062 cGy(IMRT), 3684 cGy (3D-CRT)[oral cavity], 1768 cGy(Tomotherapy), 2151 cGy(IMRT), 4031 cGy(3D-CRT)[spinal cord] its value did not exceeded NTCP. All the treatment techniques are equated with tumor and nomal tissue doses. The 3D-CRT was worse than other techniques on dose distribution, but it is reasonable in terms of TCP and NTCP baseline Tomotherapy, IMRT -dose distribution was relatively superior- was hard to therapy to claustrophobic patients and patients with respiratory failure. Particularly, in case on Tomotherapy, it take MVCT before treatment so dose measurement will be unnecessary radiation exposure to patients. Conclusion, Tomotherapy was the best treatment technique and 2nd was IMRT, and 3rd 3D-CRT. But applicable differently depending on the the patient's condition even though dose not matter.

• Pediatric Infection and Vaccine
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• v.15 no.2
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• pp.121-128
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• 2008

Purpose : The seasonality of influenza virus and rotavirus are well recognized in winter and so viral surveillance and laboratory-based diagnostics are important to guide the timing of prophylaxis and other interventions. Yet the seasonality of these two viruses are changing in Korea. We evaluated the prevalence and clinical features of influenza virus and rotavirus. Methods : From September 2001 to August 2005, nasopharyngeal aspirates were cultured from the hospitalized patients with lower respiratory infections and the stools from hospitalized patients with gastroenteritis were tested for rotavirus. We retrospectively analysed the medical records. Results : During the study period, respiratory virus was isolated in 578 (18.5%) out of 3,121 patients. Influenza virus was isolated in 143 cases. The seasonal distribution of influenza infection was from December to June of the next year. The ratio of males to females was 1.3:1 and the median age was 17 months. The most common diagnosis of influenza infection was bronchiolitis. Fever and cough were present in 94.4% and 83.9% of the patients, respectively. During the same period, 3,850 patients were admitted for gastroenteritis and 1,047 (27%) patients were positive for rotavirus. Rotavirus was prevailed from December to June of the next year and it presented in year-round. The ratio of males to females was 1.1:1 and the median age was 16 months. Diarrhea and vomiting were the most common symptoms. Conclusion : The recent peak prevalence of influenza virus and rotavirus in Korea was in winter and the late spring, respectively. So we need to expand surveillance and carefully consider the correct period to vaccinate people.

• Pediatric Infection and Vaccine
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• v.27 no.2
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• pp.117-126
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• 2020

Purpose: Epstein-Barr virus (EBV) infection is related to infectious mononucleosis or nasopharyngeal cancer, and its epidemiology may change according to the socioeconomic development of communities. This study aimed to evaluate the recent epidemiology of EBV seropositive rate in Korea. Methods: We retrospectively reviewed EBV serology test results obtained from a part of clinical care at Samsung Medical Center, Seoul, South Korea, from January 2000 to December 2017. Results: The EBV seropositive rate in 26,527 subjects during the study period was 81.0% (21,485/26,527): 44.4% (2,716/6,122) in subjects aged 0-9 years, 75.8% (2,077/2,739) in those aged 10-19 years, and 94.5% (16,692/17,666) in those aged ≥20 years. The EBV seropositive rate decreased from 89.4% (8,592/9,616) in 2000-2008 to 76.2% (12,893/16,911) in 2009-2017 (P<0.001). Especially, the EBV seropositive rate in subjects aged 0-19 years significantly decreased from 2000-2008 to 2009-2017 (0-9 years, 62.8% [1,172/1,866] in 2000-2008 and 36.3% [1,544/4,256] in 2009-2017; 10-19 years, 83.8% [745/858] in 2000-2008 and 70.8% (1,332/1,881) in 2009-2017) (P<0.001). Conclusions: The EBV seropositive rate in children has decreased in the last 20 years. As the age of patients with primary EBV infection increased, there is a need for interest in clinical manifestation, such as infectious mononucleosis, in adolescents and young adults.

• Pediatric Infection and Vaccine
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• v.5 no.2
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• pp.258-266
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• 1998

Purpose : Cases of adenoviral penumonia with rapidly progressive clinical course were experienced. We reviewed these patients in viewpoint of clinical manifestation and adenoviral serotypes. Methods : Culture and indirect immunofluorescence for respiratory viruses including respiratory syncytial virus, influenza virus, parainfluenza virus, adenovirus was done with nasopharyngeal aspirates from patients who admitted due to respiratory infections in Fatima Hospital, Masan from Nov. 1996 to Jul. 1997. Cultured adenovirus was serotyped by both neutralization and hemagglutination inhibition test. Medical records were reviewed for 5 patients with respiratory failure from adenovirus was isolated and serotyped. Results : The total number of examined patients was 460 patients. We isolated respiratory viruses in 143(30.9%) patients. Adenovirus was isolated from 66 out of 143(46.2%) patients. During Jan 1997 to May 1997, five patients with ages of 18 days to 11 months who were infected by adenovirus and had high fever with dyspnea and required assisted mechanical ventilation. One patients discharged against doctor's advice then died. Two of four patients had complications of disseminated intravascular coagulation; two had bronchiolitis obliterans. Two isolates were serotype 7, and one was serotype 5, and two were untyped. Conclusion : Severe pneumonia caused by serotype 7 continued to occur in 1997 following the epidemic in 1996, and severe pneumonia may also be caused by serotype 5 and other serotypes.

• Journal of Chest Surgery
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• v.33 no.6
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• pp.445-468
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• 2000

Background: Retrograde cerebral perfusion(RCP) is currently used for brain protection during aorta surgery, however, for the safety of it, various data published so far are insufficient. We performed RCP using pig and investiaged various parameters of cerebral metabolism and brain injury after RCP under deep hypothermia. Material and Method: We used two experimental groups: in group I(7 pigs, 20 kg), we performed RCP for 120 minutes and in group II (5 pigs, 20 kg), we did it for 90 minutes. Nasopharyngeal temperature, jugular venous oxygen saturation, electroencephalogram were continuously monitored, and we checked the parameters of cerebral metabolism, histological changes and serum levels of neuron-specific enolose(NSE) and lactic dehydrogenase(LDH). Central venous pressure during RCP was mainained in the range of 25 to 30 mmHg. Result: Perfusion flow rates(ml/min) during RCP were 130$\pm$57.7(30 minutes), 108.6$\pm$55.2(60 minutes), 107.1$\pm$58.8(90 minutes), 98.6$\pm$58.7(120 minutes) in group I and 72$\pm$11.0(30 minutes), 72$\pm$11.0(60 minutes), 74$\pm$11.4(90 minutes) in group II. The ratios of drain flow to perfusion flow were 0.18(30 minutes), 0.19(60 minutes), 0.17(90 minutes), 0.16(120 minutes) in group I and 0.21, 0.20, 0.17 in group II. Oxygen consumptions(ml/min) during RCP were 1.80$\pm$1.37(30 minutes), 1.72$\pm$1.23(60 minutes), 1.38$\pm$0.82(90 minutes), 1.18$\pm$0.67(120 minutes) in group I and 1.56$\pm$0.28(30 minutes), 1.25$\pm$0.28(60 minutes), 1.13$\pm$0.26(90 minutes). We could observe an decreasing tendency of oxygen consumption after 90 minutes of RCP in group I. Cerebrovascular resistance(dynes.sec.cm-5) during RCP in group I incrased from 71370.9$\pm$369145.5 to 83920.9$\pm$49949.0 after the time frame of 90 minutes(p<0.05). Lactate(mg/min) appeared after 30 minutes of RCP and the levels were 0.15$\pm$0.07(30 minutes), 0.18$\pm$0.10(60 minutes), 0.19$\pm$0.19(90 minutes), 0.18$\pm$0.10(120 minutes) in group I and 0.13$\pm$0.09(30 minutes), 0.19$\pm$0.03(60 minutes), 0.29$\pm$0.11(90 minutes) in group II. Glucose utilization, exudation of carbon dioxide, differences of cerebral tissue acidosis between perfusion blood and drain blood were maintained constantly during RCP. Oxygen saturation levels(%) in drain blood during RCP were 22.9$\pm$4.4(30 minutes), 19.2$\pm$4.5(60 minutes), 17.7$\pm$2.8(90 minutes), 14.9$\pm$2.8(120 minutes) in group I and 21.3$\pm$8.6(30 minutes), 20.8$\pm$17.6(60 minutes), 21.1$\pm$12.1(90 minutes) in group II. There were no significant changes in cerebral metabolic parameters between two groups. Differences in serum levels of NSE and LDH between perfusion blood and drain blood during RCP showed no statistical significance. Serum levels of NSE and LDH after resuming of cardipulmonary bypass decreased to the level before RCP. Brain water contents were 0.73$\pm$0.03 in group I and 0.69$\pm$0.06 in group II and were higher than those of the controls(p<0.05). The light microscopic findings of cerebral neocortex, basal ganglia, hippocampus(CA1 region) and cerebellum showed no evidence of cerebral injury in two groups and there were no different electron microscopy in both groups(neocortex, basal ganglia and hippocampus), but they were thought to be reversible findings. Conclusion: Although we did not proceed this study after survival of pigs, we could perform the RCP successfully for 120 minutes with minimal cerebral metabolism and no evidence of irreversible brain damage. The results of NSE and LDH during and after RCP should be reevaluated with survival data.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.330-338
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• 2009

Purpose : The causes of acute lower respiratory tract infection (ALRTI) are mostly attributable to viral infection, including respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus A/B (IFV A/B), or adenovirus (ADV). Several Korean studies reported human metapneumovirus (hMPV) as a common pathogen of ALRTI. However, studies on seasonal distribution and clinical differences relative to other viruses are insufficient, prompting us to perform this study. Methods : From November 2006 to October 2007, we tested nasopharyngeal aspiration specimens in children hospitalized with ALRTI with the multiplex reverse transcriptase-polymerase chain reaction to identify 6 kinds of common pathogen (hMPV, RSV, PIV, IFV A/B, and ADV). We analyzed positive rates and clinical features by respiratory chart review. Results : We detected 38 (8.4%) hMPV-positive cases out of 193 (41.8%) virus-positive specimens among 462 patients. HMPV infection prevailed from March to June with incidence peaking in April. HMPV-positive patients were aged 15 years (76.3%), and the ratio of boys to girls was 1.2:1. The median age was 27 months. HMPV primarily caused pneumonia (76.3 %) (P=0.018). Average hospitalization of HMPV-associated ALRTI patients was 5.8 days. In addition, they showed parahilar peribronchial infiltration (100%) on chest X-ray, normal white blood cell count (73.7%), and negative C-reactive protein (86.8 %) (P>0.05). All hMPV-positive patients recovered without complication. Conclusion : HMPV is a common pathogen of ALRTI in Korean children, especially in 1-5 year olds, from March to May. Immunocompetent children diagnosed with hMPV-associated ALRTI may have a good prognosis.

• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.178-183
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• 2010

Purpose : The aim of this study was to identify mutations associated with macrolide resistance in Mycoplasma pneumoniae (MP) and to establish a cultural method to determine antimicrobial susceptibility. Methods : Nasopharyngeal aspirates (NPAs) were collected from 62 children diagnosed with MP pneumonia by a serologic method or polymerase chain reaction. The 23S rRNA and L4 ribosomal protein genes of MP were amplified and sequenced. To identify mutations in these 2 genes, their nucleotide sequences were compared to those of the reference strain M129. MP cultivation was carried out for 32 (28 frozen and 5 refrigerated) NPAs and M129 strain using Chanock's glucose broth and agar plate in a 5% $CO_2$ incubator at $37^{\circ}C$ and examined at 2-3 day intervals for 6 weeks. Results : Among the 62 specimens, 17 had M144V mutations in ribosomal protein L4. The A2064G mutation was observed in 1 specimen; its 23S rRNA gene was successfully sequenced. Culture for MP was successful from the M129 strain and 2 of the 5 NPAs that were refrigerated for no longer than 3 days. However, MP did not grow from the 28 NPAs that were kept frozen at $-80^{\circ}C$ since 2003. Conclusion : We found the M144V mutation of L4 protein to be common and that of domain V of 23S rRNA gene was relatively rare among MP. Studies on the prevalence of macrolide-resistant MP and the relationship between the mutations of 23S rRNA gene and ribosomal protein L4 will aid in understanding the mechanism of macrolide resistance in MP.

• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.834-841
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• 2008

Purpose : This study was perfomed to analyze in detail the viral etiology of acute lower respiratory tract infections (ALRI) in Cheunan, Korea by multiplex RT-PCR, including human rhinovirus (hRV) and newly identified viruses such as human metapneumovirus (hMPV) and human coronavirus (HCoV-OC43, HCoV-229E/NL63). Method : Nasopharyngeal aspirates (NPA) were collected from 863 hospitalized children with ALRI on the first day of admission at Soonchunhyang University Cheonan Hospital and analyzed by multiplex RT-PCR from December 2005 to November 2006. Results : Viral agents were detected from 474 subjects (54.9%). The identified viral pathogens were hRV 9.2%, hMPV 6.8%, HCoV-229E/NL63 1.4%, and HCoV-OC43 2.1%. Coinfections with ${\geq}2$ viruses were observed in 108 patients (22.8%). The major period of viral ALRI was the first year of life. Clinical diagnoses of viral ALRI were pneumonia (59.5%), bronchiolitis (24.7%), tracheobronchitis (11.4%), and croup (4%). The most common causes of bronchiolitis was respiratory syncytial virus B (RSV B), whereas hMPV, hRV, HCoV-229E/NL63, and HCoV-OC43 were commonly found in patients with pneumonia. The number of hMPV infections peaked between March and May 2006. HCoV-OC43 was prevalent from November to February 2006, whereas HCoV-229E and hRV were detected throughout the year. Conclusion : Although the study was confined to one year, hMPV was not detected during winter and peaked between March and April, which was not consistent with previous studies'. This present study indicates that HCoV is a less common respiratory pathogen in cases of ALRI in Korean children

• Pediatric Infection and Vaccine
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• v.5 no.1
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• pp.79-87
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• 1998

Purpose : The P1 protein of Mycoplasma pneumoniae mediates the attachment of the pathogen to its host cell and elicits a strong humoral immune response during infection with this organism. Mycoplasma pneumoniae strains can be classified into two groups(I and II) by PCR method of P1 cytadhesin gene. In this study, we evaluated the prevalence, epidemiological and clinical characteristics of each group. Methods : From 155 patients with Mycoplasma pneumoniae, who admitted to the Department of Pediatrics, Sung-Ae and Kwangmyung Sung-Ae Hospital between November 1996 and October 1997, we collected their throat swabs or nasopharyngeal aspirates for DNA extraction and serum for indirect hemagglutination test of Mycoplasma pneumoniae. The group specific PCR amplification were performed using specific oligonucleotide primers designed for P1 gene genotyping. Results : Group I(137 patients, 88.4%) occurred frequently than group II(18 patients, 11.6%). In both group, the most prevalent season was winter in 1996(Nov. to Dec.) and fall in 1997(Aug. to Oct.) The prevalent age was four to six years old. The number of male was more than female in both group; Group 1(1.2:1), Goup 2(1.6:1). No significant relationship were found between two groups in duration of fever and hospital days(P>0.05). The rate of high antibody titers(>1:5120) was lower in group I(6/137, 4.4%) than group II(2/18, 11.1%). Conclusion : Group I was much more prevalent than group II during 1996~1997 in Korea. There was no difference between two groups in epidemiological and clinical parameters except the rate of high antibody titers. Further follow-up survey will be needed for the epidemiologic and clinical studies of Mycoplasma pneumoniae in Korea.

• Pediatric Infection and Vaccine
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• v.9 no.2
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• pp.193-200
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• 2002

Purpose : This study was performed to investigate the epidemiology of viral acute lower respiratory tract infection(ALRI) in two different areas of Korea. Methods : A total of 796 patients hospitalized for ALRI aged 15 years or less from June 2000 to June 2001 in Samsung Seoul hospital(SSH) and Masan Fatima hospital(MFH) were enrolled. Viral etiologies were confirmed using nasopharyngeal aspirates. We compared etiologic agents, age distribution, clinical manifestations, and seasonal occurrence of viral ALRI between the two hospitals. Results : Virus was isolated in 208 patients(26.1%). The proportion of patients aged under 2 years in SSH was 60.2%, while those in MFH was 90.0%(P<0.05). Respiratory syncytial virus(RSV) was more prevalent in MFH, but adenovirus, influenza virus and parainfluenza virus were more prevalent in SSH(P<0.05). Croup and bronchiolitis occurred more frequently in MFH than in SSH(P<0.05). The most frequent viral pathogens causing bronchiolitis and croup were RSV and parainfluenza virus, respectively, in both hospitals. Adenovirus was the main cause of pneumonia in SSH, in contrast to RSV in MFH. In terms of tracheobronchitis, adenovirus was detected most frequently in SSH, whereas influenza virus-type A was mainly isolated in MFH. Similar pattern of seasonal occurrences of RSV, parainfluenza virus and influenza virus-type A was noted in both hospitals. Adenovirus was isolated sporadically throughout the study periods. Conclusion : Seasonal occurrence and clinical syndromes according to viral pathogens showed similar pattern in two areas. However, distribution of offending viruses was different, although this is mainly related to the different age distribution. An annual nationwide surveillance is necessary to understand the viral epidemiology associated with respiratory illnesses in Korea.