• Investigative Magnetic Resonance Imaging
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• v.13 no.2
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• pp.137-145
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• 2009

Purpose : To compare 12 and 32-element surface coil arrays for highly accelerated coronary magnetic resonance angiography (MRA) using parallel imaging. Materials and Methods : Steady state free precession coronary MRA was performed in 5 healthy volunteers at 1.5 T whole body MR scanner using both 12 and 32-element surface coil arrays. Left anterior descending and right coronary artery data sets were acquired for each volunteer. Data sets were sub-sampled for parallel imaging using reduction factors from 1 to 6. Mean geometry factor (g-factor), maximum g-factor, and artifact level were calculated for each of the two coil arrays. Results : Over all reduction factors, the mean and maximum g-factors and artifact level were significantly reduced using the 32-element array compared to the 12element array (P << 0.1). The mean g-factor was sensitive to the imaging orientations of coronary arteries while the maximum g-factor and artifact level were independent of orientation. Conclusion : The 32-element surface coil array significantly improves artifact and noise suppression for highly accelerated coronary MRA using parallel imaging. The increased acceleration factors made feasible with the 32-element array offer the potential to enhance spatial resolution or increase volumetric coverage for 3D coronary MRA.

• Progress in Medical Physics
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• v.18 no.3
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• pp.149-160
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• 2007

Recent advent of 64-multidetctor (MD) CT enables more coverage of Z-axis in the perfusion imaging. The purpose of this study was to evaluate the clinical usefulness of perfusion CT by using 64-MD CT in detecting the lesion in patients with acute stroke. The perfusion CT was performed by using 64-MD CT in 62 consecutive patients who were initially suspected to have subacute ischemic stroke symptoms during the period of recent 9 months. These patients had subacute stroke (n=62). CT scanning was conducted with Jog Mode which provided 16 imaging slices with 5 mm of slice thickness, and 8 cm of coverage in Z-axis. Scan interval was 1 seconds for each imaging slice and total 15 scans were repeated. After CT scanning, perfusion maps (CBV, CBF, MTT and TTP) were created at Extended Brilliance Workstation. The CBV and CBF maps showed that lesions were smaller images. While on the MTT and TTP map lesions were seen to be larger fifty-one were large than they appeared on these images. Two slices of perfusion maps obtained at the level of the basal ganglia were chosen to simulate conventional older perfusion CT with 8 cm of coverage in Z-axis. TTP and MTT maps may be clinically useful for evaluation of the penumbral zone in cases of aubacute cerebral ischemic stroke. The perfusion CT is useful in the assessment of acute stroke as an initial imaging modality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.208-218
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• 2017

Objective: This study examined the caregiver burden, depressive symptoms, and mental-related quality of life of 226 caregivers of stroke patients, who had been hospitalized in 7 general hospitals located in Cheongju and Daejeon Metropolitan city. Methods: Data were collected from August 5, 2014 to October 5, 2014 and a structured self-administered questionnaire was used. The results were analyzed using a t-test, ANOVA for different comparisons of the mental related quality of life in the sociodemographic characteristics, care-related characteristics, health-related behavioral characteristics, caregiver burden, and depressive symptoms. Hierarchical multiple regression was conducted to determine the explanatory power of the independent variables on the dependent variables, with the variables showing significant differences in univariate analysis as independent variables. Results: According to the results of hierarchical multiple regression analysis, the relevant factors that influenced the mental-related quality of life were the relationship with a patient, burden by 'care', burden by sacrifice of 'personal life', and depressive symptoms. Conclusion: To enhance health-related quality of life, not only is a systematic complement on such factors needed, but the development and implementation of an intervention program to the caregiver burden and depressive symptoms is also urgently required.

• Journal of radiological science and technology
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• v.32 no.4
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• pp.371-380
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• 2009

This study was executed to find out the intensity of turnover intention and its associated factors of radiologic technologists who worked for private clinic and university hospitals in Daejoen. Such variables as social and demographic characteristics, job-related features, job stress, job satisfaction, job performance, organizational commitment and turnover intention were investigated based on the survey of randomly sampled 400 radiologic technologists. The results are summarized as follows. 1. College graduates of private clinic workers were significantly higher than junior college graduates of them in the mean score for turnover intention. And low age groups, unmarried group, no religion group, low job career groups and low income groups of university hospital workers were significantly higher than high age groups, married group, religion group, high job career groups and high income groups of them respectively in the mean score for turnover intention. 2. Private clinic and university hospital workers' low and high groups in the variables of job demand, job control, supervisor support, job satisfaction, organizational commitment showed significant difference in the mean score for turnover intention. specially private clinic workers' low and high groups in the variables of coworker support, job performance showed significant difference in the mean score for turnover intention. 3. A hierarchial multiple regression analysis was conducted to catch the influence of related variables on turnover intention according to private clinic workers and university hospital workers. As a result of the analysis, the higher the degrees of education and job demand were and the lower the degree of job satisfaction was for private clinic workers, the higher the degree of turnover intention was. And the lower the degrees of age, job career, job satisfaction and organizational commitment were for university hospital workers, the higher the degree of turnover intention was. In conclusion, it was found that job demand and job satisfaction for private clinic workers and job satisfaction and organizational commitment for university hospital workers influenced on turnover intention.

• Progress in Medical Physics
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• v.18 no.2
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• pp.55-64
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• 2007

Our objective was to evaluate the clinical feasibility of spatial domain filtering as an alternative to additional image reconstruction using different kernels in CT. Kernels were grouped as H30 (head medium smooth), B30 (body medium smooth), S80 (special) and U95 (ultra sharp). Derived from thin coilimated source images, four sets of images were generated using phantom kernels. MTF (50%, 10%, 2%) measured with H30 (3.25, 5.68, 7.45 Ip/cm) B30 (3.84, 6.25, 7.72 Ip/cm), S80 (4.69, 9.49, 12.34 Ip/cm), and U95 (14.19, 20.31, 24.67 Ip/cm). Spatial resolution for the U95 kernel (0.6 mm) was 33.3% greater than that of the H30 and B30 (0.8 mm) kernels. Initially scanned kernels images were rated for subjective image qualify, using a five-point scale. Image scanned with a convolution kernel led to an increase in noise (U95), whereas the results for CT attenuation coefficient were comparable. CT images increase the diagnostic accuracy in head (H30), abdomen (B30), temporal bone and lung (U95) kernels may be controlled by adjusting CT various algorithms, which should be adjusted to take into account the kernels of the CT undergoing the examination.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.55-74
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• 1996

This study was carried out to improve service efficiency and to cope with a emergency situation in emergency radiography, through analysis of the radiographic distribution and literature cited about emergency care. Data collection of radiographic distribution was surveyed for 761 emergency outpatients who visit during JAN, 1994 at ER of the general hospital in Pusan city. The results is as follows: Emergency radiography rate of simple radiography was 61.1 %, special radiography 2.5 %, CT 12.6 %, and ultrasonography 6.7 %. In simple radiography rate, a high rate was distributed on male(63.6 %), thoracicsurgery part(90.0%), admission patient(74.9 %), and long stayed patient at ER. In special raiography rate, a high rate was observed in urologic part(28.6%), and in CT rate, observed neurosurgery part(49.2 %) and neurologic part(36.7%). Ultrasonography rate was high for female(8.8 %) and internal medicine part(15.9 %). There are distributed regional radiography rate in radiographic type that chest(55.3 %) is high in the simple radiography, urinary system(1.2%) in the special study, and brain(40.0 %) in the CT. Regional radiography rate according to diagnostic department also was showed highly for head(64.6%) in neurosurgery, chest(90.0%) in thoracic-surgery, abdomen(58.0%) in general-surgery, spine (40.0% ) in neuro-surgery, and pelvis(15.9%), upper extrimity(20.5%), and lower extrimity(31.8%) in orthopedic-surgery each. Mean radiographic case number per patient of simple radiography was sinificant on sex, age, transfer relation in both total and radiographic patients(p<0.05). Mean radiographic case number was highly distributed on male(2.2 case number) in sex, on thirties(2.7) in age, transfered patient(2.7) in patient type, and on neurosurgery(3.4) in diagnostic charged part. Total radiographic case number in regional part was highly distributed on chest(499 case number). Considering the above results, emergency radiographer should take care of the elder patient in emergency radiography and get hold of injury mechanism to decrease possible secondary injury during radiography. Because of high radiography rate of urinary system in special study, radiographer should know well about dealing with contrastmedia administration and related instrument. All radiographer who take charge emergency patient should cope with a emergency situation during radiography, Because head trauma patients is very important in patient care, especilly in CT at night, charged doctor should be always silted with CT room and monitoring-patient. Radiography was reqested by many diagnostic department in ER. Considering that rate of simple radiography is high, special room for emergency radiography should be established in ER area, and the radiographer of this room should be stationed radiologic technician who is career and can implement emergency patient care.

• Journal of Life Science
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• v.21 no.6
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• pp.893-900
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• 2011

Prostatic acid phosphatase (PAP) is one of the widely used biomarkers in the diagnosis of prostate cancer. It was initially identified in 1935 and is the most abundant phosphatase in the human prostate. PAP is a prostate-specific enzyme that is synthesized in prostate epithelial cells. It belongs to the acid phosphatase group that shows enzymatic activity in acidic conditions. PAP is abundant in prostatic fluid and is thought to have a role in fertilization and oligospermia. It also has a potential role in reducing chronic pain. But one of the most apparent functions of PAP is the dephosphorylation of macromolecules such as HER-2 and PI3P that are involved in the ERK1/2 and MAPK pathways, which in turn leads to inhibition of cell growth and tumorigenesis. Currently, clinical trials using PAP DNA vaccine are underway and FDA-approved immunotherapy using PAP is commercially available. Despite these clinically important aspects, molecular mechanisms underlying PAP regulation are not fully understood. The promoter region of PAP was reported to be regulated by NF-${\kappa}B$, TNF-${\alpha}$, IL-1, androgen and androgen receptors. Here, the features of PAP gene and protein structures together with the function, regulation and roles of PAP in prostate cancer are discussed.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.375-381
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• 2015

Digital Radiography is a big part of diagnostic radiology. Because uncorrected digital radiography image supported false effect of Patient's health care. We must be manage the correct digital radiography image. Thus, the artifact images can have effect to make a wrong diagnosis. We report types of occurrence by analyzing the artifacts that occurs in digital radiography system. We had collected the artifacts occurred in digital radiography system of general hospital from 2007 to 2014. The collected data had analyzed and then had categorize as the occurred causes. The artifacts could be categorized by hardware artifacts, software artifacts, operating errors, system artifacts, and others. Hardware artifact from a Ghost artifact that is caused by lag effect occurred most frequently. The others cases are the artifacts caused by RF noise and foreign body in equipments. Software artifacts are many different types of reasons. The uncorrected processing artifacts and the image processing error artifacts occurred most frequently. Exposure data recognize (EDR) error artifacts, the processing error of commissural line, and etc., the software artifacts were caused by various reasons. Operating artifacts were caused when the user didn't have the full understanding of the digital medical image system. System artifacts had appeared the error due to DICOM header information and the compression algorithm. The obvious artifacts should be re-examined, and it could result in increasing the exposure dose of the patient. The unclear artifact leads to a wrong diagnosis and added examination. The ability to correctly determine artifact are required. We have to reduce the artifact occurrences by understanding its characteristic and providing sustainable education as well as the maintenance of the equipments.

• Journal of radiological science and technology
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• v.34 no.3
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• pp.203-208
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• 2011

In this study, we investigated factors for affecting pneumothorax in percutaneous needle aspiration biopsy of lung lesions. This research were conducted at University Hospital in Daejeon from August 2007 to May 2008. Total 104 patients between the ages of 25~85 who had focal lung lesions were grouped in terms of the tumor location, tumor size, depth of lesion, gender, age, biopsy time, and the number of biopsies. Then, their correlations with pneumothorax were studied. The incidence of pneumothorax according to the positions showed 27.3% in the right lower lobe, 24.3% in the right upper lobe, 15% in the left lower lobe and 12% in the left upper, respectively. In addition, the incidence by lesion size showed 24.0% in 0~2.0 cm, 18.2% in 2.1~4.0 cm, above 20.0% in 4.1 cm respectively. The probabilities of pneumothorax was 6.7% at 0 cm depth of lesion, 24.2% at 0.1~2.0 cm and greater than 26.8% at 2.1 cm. By gender differences, we found that probability of incidence of pneumothrax is 21.7% for male and 17.1% for female. According to age, pneumothorax occurred in 25% in the group of less than 40-years-old, 11.7% in 41~50 years, 14.3% in 51~60 years, 24.1% in 61~70 years old and 24.1% in over 70 years. According to the time of biopsy, the incidence of pneumothorax was 3.8% from 0 to 10.0 minutes, 18.9% from 10.1 to 20.0 minutes and 40% more than 21 minutes.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.163-170
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• 2016

To evaluate whether the difference in geometrical characteristics between high-dose-rate (HDR) $^{192}Ir$ sources would influence the dose distributions of intracavitary brachytherapy. Two types of microSelectron HDR $^{192}Ir$ sources (classic and new models) were selected in this study. Two-dimensional (2D) treatment plans for classic and new sources were generated by using PLATO treatment planning system. We compared the point A, point B, and bladder and rectum reference points based on ICRU 38 recommendation. The radial dose function of the new source agrees with that of the classic source except difference of up to 2.6% at the nearest radial distance. The differences of anisotropy functions agree within 2% for r=1, 3, and 5 cm and $20^{\circ}$ < ${\theta}$ < $165^{\circ}$. The largest discrepancies of anisotropy functions reached up to 27% for ${\theta}$ < $20^{\circ}$ at r=0.25 cm and were up to 13%, 10%, and 7% at r=1, 3, and 5 cm for ${\theta}$ > $170^{\circ}$, respectively. There were no significant differences in doses of point A, point B, and bladder point for the treatment plans between the new and classic sources. For the ICRU rectum point, the percent dose difference was on average 0.65% and up to 1.0%. The dose discrepancies between two treatment plans are mainly affected due to the geometrical difference of the source and the sealed capsule.