The purpose of this study was to evaluate the convenience and image quality of patients with acute lumbar pain patients at a general hospital in Daejeon using ancillary devices for postural changes and correction. The results of the study are summarized as follows. First, the Turbo S pin Echo technique(TS E) using ancillary equipment has the highest image evaluation rating with an average score of 4.440, which is highly valuable on a diagnosis. Second, the average score for patient the questionnaire 'When using ancillary equipment, I feel that my body is calibrated to side without bias.' was shown as 4.440, which is very useful for the correction of the patient's body when using ancillary equipment. Finally, Breath Hold technique(BH) is very effective in shortening test time of acute lumbar pain patients, because it can reduce test time 86.4% faster than Turbo Spin Echo technique(TSE). The results of the study showed that the use of ancillary equipment to perform the test through the side lying postures helped to reduce the pain and control the patient's breathing, and the diagnostic value of the image was high.

The purpose of this study is to evaluate the performance of a "stealth chamber" as a novel reference chamber for measuring percentage depth dose (PDD) and profile of 6, 8 and 10 MV photon energies. The PDD curves and dose profiles with fields ranging from $3{\times}3$ to $25{\times}25cm^2$ were acquired from measurements by using the stealth chamber and CC 13 chamber as reference chamber. All measurements were performed with Varian VitalBeam linear accelerator. In order to assess the performance of stealth chamber, PDD curves and profiles measured with stealth chamber were compared with measurement data using CC13 chamber. For PPDs measured with both chambers, the dosimetric parameters such as $d_{max}$ (depth of maximum dose), $D_{50}$ (PDD at 50 mm depth), and $D_{100}$ (PDD at 100 mm depth) were analyzed. Moreover, root mean square error (RMSE) values for profiles at $d_{max}$ and 100 mm depth were evaluated. The measured PDDs and profiles between the stealth chamber and CC13 chamber as reference detector had almost comparable. For PDDs, the evaluated dosimetric parameters were observed small difference (<1%) for all energies and field sizes, except for $d_{max}$ less than 2 mm. In addition, the difference of RMSEs for profiles at $d_{max}$ and 100 mm depth was similar for both chambers. This study confirmed that the use of stealth chamber for measuring commission beam data is a feasible as reference chamber for fields ranging from $3{\times}3$ to $20{\times}20cm^2$. Furthermore, it has an advantage with respect to measurement of the small fields (less than $3{\times}3cm^2$ field) although not performed in this study.

The results of CBCT was obtained using image guided radiation therapy for radiation therapy in 5 prostate cancer patients. Using these results, we compared and evaluated the dose changes according to the treatment plan depending on the volume and position of bladder, rectum, and prostate. The 28 images of CBCT were acquired using On-Board Imaging device before radiotherapy. After the outline of bladder, rectum, and PTV, pCT images and CBCT images for radiotherapy were treated respectively. The volume of the bladder was increased by 105.6% and decreased by 45.2%. The volume of the rectum was increased by 30.5% and decreased by 20.3%. Prostate volume was increased by 6.3% and decreased by 12.3%. The mean dose of the rectum was higher in the CBCT than in the pCT, and V40 (equivalent to 40 Gy) of the bladder showed a reduction in all treatment regimens in the CBCT than in the pCT. Conformity treatment and homogeneity index of PTV showed better results in all treatment regimens using pCT than CBCT. It was found that the dose distribution of the pelvic internal organs varied greatly according to the patient 's condition and pretreatment.

Cone beam Computed Tomography(CBCT) is an increasing trend in clinical applications due to its ability to increase the accuracy of radiation therapy. However, this leaded to an increase in exposure dose. In this study, the simulation using Monte Carlo method is performed and the absorbed dose of CBCT is analyzed and standardized data is presented. First, after simulating the CBCT, the photon spectrum was analyzed to secure the reliability and the absorbed dose of the tissue in the human body was evaluated using the MIRD phantom. Compared with SRS-78, the photon spectrum of CBCT showed similar tendency, and the average absorbed dose of MIRD phantom was 8.12 ~ 25.88 mGy depending on the body site. This is about 1% of prescription dose, but dose management will be needed to minimize patient side effects and normal tissue damage.

The purpose of this study is to present the reference values for cardiac size and cardiothoracic ratio change, normal range and diagnosis of cardiovascular disease in pregnancy and non pregnancy of normal Korean women using chest X-ray. The subjects of this study were 58 women, who were read as normal by chest radiologist, had chest radiography taken on both last month of pregnancy, pre-pregnancy and within 2 years following delivery. In this study, we defined the last month of pregnancy as pregnancy and before or post pregnancy as non-pregnancy. CS and CTR were measured by two radiological technologist who had clinical experience more ten years with Danzer's method. Statistical methods were paired t-test and one-way ANOVA. Significance level ${\alpha}$ was 0.05 and p-value 0.05 or less was statistically significant. For pregnancy, the mean of left and right cardiac size was $40.11{\pm}8.73mm$ and $89.51{\pm}11.9mm$, CS was $128.60{\pm}13.15mm$, CTR was $44.51{\pm}4.21%$. In non pregnancy, $36.50{\pm}8.18mm$ and $77.68{\pm}13.1mm$. CS and CTR were $114.18{\pm}14.28mm$ and $42.03{\pm}4.04%$. Both pregnancy and non pregnancy, the difference of the mean value in left and right cardiac size, CS and CTR were statistically significant (p<0.01). but comparing mean on age, height and weight, the difference of the mean value between groups was not (p>0.05). In the result of this study, the mean size of CS increased by 12.6% in pregnancy($128.60{\pm}13.15mm$) compared to the non pregnancy($114.18{\pm}14.28mm$), and increased by 9.8% in the right side of the heart and 15.2% in the left side. The mean size of CTR increased about 5.9% in pregnancy ($44.5{\pm}4.21%$) compared to non pregnancy($42.03{\pm}4.04%$).

Automated breast ultrasound (ABUS) equipment is a new innovative technique for 3D automatic breast scanning, but limited for the examination in the concave axillary region. The purpose of this study was to determine feasible candidate materials for the ultrasonic wave propagation media in ABUS, enabling the evaluation of the axillary region. Ultrasonography was performed using an ABUS system ($Invenia^{TM}ABUS$, GE, USA) on the ultrasound-specific phantom (UC-551M-0.5, ATS Laboratories, USA) covered by different candidate materials. The validity of feasible candidate materials was evaluated by image quality. Three independent radiological technologists, with more than 10 years of experience, visually assessed on the images. The inter-observer agreements according to the candidate materials were tested using Cronbach's alpha. Unenveloped solidified carrageenan can be a feasible material for the use of ABUS with excellent test reliability. Therefore, the coverage of the axillary region with carrageenan may be effective for ABUS which was originally developed for the convex anatomic structure as female breast.

The purpose of this study was to compare the ultrasound gel container washing methods for the sterilization of contaminants and to find the useful methods for the prevention of infection caused by the ultrasonic gel containers. In this experiment, a 250 mL ultrasonic gel container was used, and the ultrasonic gel used was a non-sterile gel (ECO GEL 99, SeungWon Medical, Korea). In order to evaluate the degree of contamination, new 250 mL 15 containers were divided into 5 groups to perform five types of washing by no treatment, washing with water, washing with soap, washing with bottle cleaner and high disinfection level washing. After the washing process, filled the gel container with gel and after 2 weeks, the number of colonies in the gel container was sampled repeatedly twice in the same ultrasonic laboratory and compared before and after washing. As a result of among the five cleaning methods used in this study, 87.2% and 88.9% of the soapy water washing (p = 0.028) and high level washing (p = 0.027) showed significant bacterial reduction rates, respectively. Our findings conclusively an ultrasonic gel container cleaning method for removing contaminants has been found to be an effective sterilization method at a low cost with a soapy water cleaning method. Therefore, it is expected that it will be helpful to prevent the infection caused by the ultrasonic gel container by suggesting the sterilization cleaning method that is practically useful in this study.

In this study, we evaluated the DAP(Dose Area Product) reduction effect of the newly developed IRIS collimator by measuring the DAP of the Rectangle collimator and the IRIS collimator depending on the field, SID(Source to Image recpetor Distance) change, and AEC mode use. The results were as follows. The IRIS collimator decreased DAP by 34.91, 29.33, and 29.04%, respectively, compared to the Rectangle collimator when the field was increased to $8{\times}8$, $12{\times}12$, $16{\times}16inch$. And also, when the SID was increased to 100, 120 and 140 cm, the IRIS collimator decreased DAP by 10.73, 33.68 and 46.22%, respectively, compared to the Rectangle collimator. In AEC mode and none-AEC mode, DAP in IRIS collimator was reduced by 32.71 and 21.69%, respectively, compared with the Rectangle type. The IRIS collimator can reduce DAP by 29.62% on average compared to Rectangle type, which is statistically significant. These results suggest that the newly developed IRIS collimator can be used in medical field to alleviate radiation exposure.

Most patients and parents and guardians display frequent anxiety due to radiation exposure during outpatient, ward, and pediatric general radiographic examinations. This is a behavior that perceives only the harmfulness of radiation. For the recognition of medical radiation, we conduct surveys on outpatients, inpatients, and pediatric parents and guardians to identify their awareness, and then use the radiation dose promotional materials After providing accurate information on the use of radiation, the outpatient, inpatient, and pediatric parents and guardians were asked to explain the change in awareness. The questionnaire items were classified into five categories: repetitive radiation awareness for diagnosis, awareness of exposure dose, availability of exposure information, awareness of radiation risk, and awareness of health problems caused by radiation. There was a statistically significant difference in the items of recognition result of medical radiation, although there was a slight difference in the individual items in the pre and post-recognition results of providing information about the radiologists of the protector and the outpatient(p<0.05). Therefore, through the installation of these promotional materials, we will improve our awareness of medical radiation safety during general radiography surveillance in the Department of Radiology to provide better quality medical information and medical services, thereby contributing to strengthening the competitiveness of the hospital.

Most schools and educational institutions, as well as most companies, show willingness to teach CPR. However, as an essential element for the health care workers, this study aims to analyze the appropriate timing of education and improvements to the education, focusing on those who have trained for CPR. The survey was conducted for only those who applied for CPR education regardless of their profession in medical institutions. There were 105 males and 93 females by gender, and an average of 198 females were 33.5 years. The difference in CPR education depending on individual characteristics showed a high demand that all research subjects' gender, age and marital status should be improved to a practical education. During the education period, the efficiency of CPR was high. It is expected that the education of CPR will be used for the improvement of the training cycle and the training content since it is the enhancement of the performance capabilities that require practical application.