• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.317-322
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• 1989

In this paper, brain CT images are automatically segmented to reconstruct the 3-D scene from consecutive CT sections. Contextual segmentation technique was applied to overcome the partial volume artifact and statistical fluctuation phenomenon of soft tissue images. Images are hierarchically analyzed by region growing and graph editing techniques. Segmented regions are discriptively decided to the final organs by using the semantic informations.

• Journal of Trauma and Injury
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• v.27 no.3
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• pp.63-70
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• 2014

Purpose: In children, mild traumatic brain injuries (TBI) account for 70~90% of head injuries. Without guidelines, many of these children may be exposed to excess radiation due to unnecessary imaging. The purpose of this study was to evaluate the impact of a mild TBI guideline in imaging of pediatric patients. Methods: The medical records of all children who had head computed tomography and were admitted to our hospital with a TBI with Pediatric Glasgow Coma Scale and Glasgow Coma Scale of 14 to 15 were retrospectively reviewed and compared with PECARN Rule. Results: A total of 1260 children were included and all children checked with head computed tomography. 61 pediatrics had CT positive and presented skull fracture 40, hemorrhage 8, hemorrhagic contusion 7, and diffuse axonal injury 1. Also, 4 patients diagnosed both skull fracture and brain haemorrhage and 1 patient diagnosed both haemorrhage and haemorrhagic contusion. Conclusion: There are many pediatric traumatic patients who exposed to radiation due to CT. But, the most of results were negative. So, consider to follow the CT guideline for children and many do not require brain CT.

• Korean Journal of Artificial Intelligence
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• v.12 no.1
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• pp.1-6
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• 2024

Recently, various techniques are being applied through the development of medical AI, and research has been conducted on the application of super-resolution AI models. In this study, evaluate the results of the application of the super-resolution AI model to brain CT as the basic data for future research. Acquiring CT images of the brain, algorithm for brain and bone windowing setting, and the resolution was downscaled to 5 types resolution image based on the original resolution image, and then upscaled to resolution to create an LR image and used for network input with the original imaging. The SRCNN model was applied to each of these images and analyzed using PSNR, SSIM, Loss. As a result of quantitative index analysis, the results were the best at 256×256, the brain and bone window setting PSNR were the same at 33.72, 35.2, and SSIM at 0.98 respectively, and the loss was 0.0004 and 0.0003, respectively, showing relatively excellent performance in the bone window setting CT image. The possibility of future studies aimed image quality and exposure dose is confirmed, and additional studies that need to be verified are also presented, which can be used as basic data for the above studies.

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.106-106
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• 2002

Purpose： The purposes of our study are (1) to develop a brain phantom which can be used for multimodal image registration, (2) to evaluate the accuracy of image registration with the home-made phantom. Method： A brain phantom which could be used for image registration technique of CT-MR and CT-SPECT images using chamfer matching was developed. The brain phantom was specially designed to obtain imaging dataset of CT, MR, and SPECT. The phantom had an external frame with 4 N-shaped pipes filled with acryl rods for CT, MR imaging and Pb rods for SPECT imaging. 8 acrylic pipes were inserted into the empty space of the brain phantom to be imaged for geometric evaluation of the matching. Accuracy of image fusion was assessed by the comparison between the center points of the section of N-shaped bars in the external frame and the inserted pipes of the phantom. Technique with partially transparent, mixed images using color on gray was used for visual assessment of the image registration process.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2775-2780
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• 2016

Background: Precise staging of lung cancer is usually evaluated by PET-CT and brain MRI. Recently, however, whole-body diffusion-weighted magnetic resonance imaging (WB-DWI) has be applied. The aim of this study is to determine whether the diagnostic performance of lung cancer staging by WB-DWI is superior to that of PET-CT+brain MRI. Materials and Methods: PET-CT + brain MRI and WB-DWI were used for lung cancer staging before surgery with 59 adenocarcinomas, 16 squamous cell carcinomas and 6 other carcinomas. Results: PET-CT + brain MRI correctly identified the pathologic N staging in 67 patients (82.7%), with overstaging in 5 (6.2%) and understaging in 9 (11.1%), giving a staging accuracy of 0.827. WB-DWI correctly identified the pathologic N staging in 72 patients (88.9%), with overstaging in 1 (1.2%) and understaging in 8 patients (9.9%), giving a staging accuracy of 0.889. There were no significant differences in accuracies. PET-CT + brain MRI correctly identified the pathologic stages in 56 patients (69.1%), with overstaging in 7 (8.6%) and understaging in 18 (22.2%), giving a staging accuracy of 0.691. WB-DWI correctly identified the pathologic stages in 61 patients (75.3%), with overstaging in 4 (4.9%) and understagings in16(19.7%), giving a staging accuracy of 0.753. There were no significant difference in accuracies. Conclusions: Diagnostic efficacy of WB-DWI for lung cancer staging is equivalent to that of PET-CT + brain MRI.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.2
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• pp.120-125
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• 2012

Purpose : The purpose of this study was to compare count between Chang's method and CT-based attenuation correction (AC-CT) among the attenuation correction (AC) methods for non-attenuation correction (AC-non) images of Brain SPECT (Single Photon Emission Computed Tomography). Materials and Methods : We injected $^{99m}Tc$ 37Mbq in a Hoffman 3D phantom filled with distilled water in the phantom study, and injected intravenously $^{99m}Tc$-HMPAO 740Mbq in a normal volunteer in the patient study, and then obtained Brain SPECT images with Symbia T6 of Siemens and conducted quantitative brain analysis. Transverse images to which each method was applied were rebuilt at the same position, and 6 regions of interest (ROI) were drawn on each of Slice No. 10, 20 and 30 and then the counts of AC-non, AC-CT and Chang's method were compared. Results : The mean counts of AC-non, AC-CT and Chang's method were $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, and $8752.6{\pm}896.5$, respectively, in the phantom study and $5460.8{\pm}519.6$, $15320{\pm}1171.6$ and $12795{\pm}1422.1$, respectively, in the patient study. In the phantom study, the ratio of AC-CT to AC-non was 3.70 and the ratio of Chang's method to AC-non was 1.92, and in the patient study, they were 2.85 and 2.38, respectively. Conclusion : From this study, we found that AC-CT makes higher AC than Chang's method. In addition, when Chang's method was used, AC in the patient study was higher than that in the phantom study. These results need to be considered also in other examinations.

• Journal of Trauma and Injury
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• v.25 no.4
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• pp.152-158
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• 2012

Purpose: To understand the epidemiology of head trauma and the utilization of brain CT in Korea, we analyzed a national sampling data set, the National Patient Sample obtained from the Health Insurance Review and Assessment Service. Methods: We retrospectively collected and analyzed demographic and clinical data on enrolled patients from the National Patient Sample based on medical claims data for 2009. The data included patient's age, sex, treatment date, diagnosis codes, procedure codes related with CT, holiday or night consultation fee, and fee for emergency management services. Results: In 2009, the estimated population with head trauma was 819,059(1.8%), and the rate of brain CT utilization was 22.4%. Children ages 5 to 15 were the most commonly injured group(22.8%), but had the lowest brain CT utilization(16.5%). The mean age of the estimated population with head trauma was $34.9{\pm}0.5years$ old, and male patients accounted for 60.5% of that population. Intracranial injury was found in 8.6% of all head traumas, and the rate of intracranial injury in children was lower than it was in adults(4.1% vs. 10.9%, p<0.001). Twenty- three percent of patients with head trauma visited the emergency department (ED). More patients with head trauma visited medical facilities in the daytime on weekdays(66.5% vs. 33.5%, p<0.001), but head CT was performed more frequently at night or on weekends/holidays(16.1% vs. 34.7%, p<0.001) There is low incidence of head trauma in the winter in children (p<0.001). In the multivariate logistic regression analysis, patients who were adults, female, or ED visitors were more likely to undergo brain CT (odds ratio (OR): 1.65, 95% confidence interval (CI): 1.47-1.84; OR: 1.40, 95% CI: 1.27-1.54; OR: 7.80, 95% CI: 6.91-8.80, respectively). Conclusion: In this study, we analyzed the national epidemiologic trend for head trauma, and the pattern of utilization of brain CT.

• Journal of the Korean Society of Radiology
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• v.9 no.6
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• pp.369-374
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• 2015

In this study we proposed a texture feature analysis algorithm that distinguishes between a normal image and a diseased image using CT images of some brain hemorrhage patients, and generates both Eigen images and test images which can be applied to the proposed computer aided diagnosis system in order to perform a quantitative analysis for 6 parameters. And through the analysis, we derived and evaluated the recognition rate of CT images of brain hemorrhage. As the results of examining over 40 example CT images of brain hemorrhage, the recognition rates representing a specific texture feature-value are as follows: some appeared to be as high as 100% including average gray level, average contrast, smoothness, and Skewness while others showed a little low disease recognition rate: 95% for uniformity and 87.5% for entropy. Consequently, based on this research result, if a software that enables a computer aided diagnosis system for medical images is developed, it will lead to the availability for the automatic detection of a diseased spot in CT images of brain hemorrhage and quantitative analysis. And they can be used as computer aided diagnosis data, resulting in the increased accuracy and the shortened time in the stage of final reading.

• Journal of Korean Neurosurgical Society
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• v.58 no.2
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• pp.125-130
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• 2015

Objective : Repeated computed tomography (CT) follow up for traumatic brain injury (TBI) patients is often performed. But there is debate the indication for repeated CT scans, especially in pediatric patients. Purpose of our study is to find risk factors of progression on repeated CT and delayed surgical intervention based on the repeated head CT. Methods : Between March, 2007 and December, 2013, 269 pediatric patients (age 0-18 years) had admitted to our hospital for head trauma. Patients were classified into 8 subgroups according to mechanisms of injury. Types, amount of hemorrhage and amount changes on repeated CT were analyzed as well as initial Glasgow Coma Scale (GCS) scores. Results : Within our cohort of 269 patients, 174 patients received repeat CT. There were progression in the amount of hemorrhage in 48 (27.6%) patients. Among various hemorrhage types, epidural hemorrhage (EDH) more than 10 cc measured in initial CT was found to be at risk of delayed surgical intervention significantly after routine repeated CT with or without neurological deterioration than other types of hemorrhage. Based on initial GCS, severe head trauma group (GCS 3-8) was at risk of delayed surgical intervention after routine repeated CT without change of clinical neurologic status. Conclusion : We suggest that the patients with EDH more than 10 cc or GCS below 9 should receive repeated head CT even though absence of significant clinical deterioration.

• Journal of Radiation Protection and Research
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• v.46 no.1
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• pp.1-7
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• 2021

Background: The use of computed tomography (CT) device has increased in the past few decades in Japan. Dose optimization is strongly required in pediatric CT examinations, since there is concern that an unreasonably excessive medical radiation exposure might increase the risk of brain cancer and leukemia. To accelerate the process of dose optimization, continual assessment of the dose levels in actual hospitals and medical facilities is necessary. This study presents organ dose estimation using pediatric cerebral CT scans in the Kyushu region, Japan in 2012 and the web-based calculator, WAZA-ARI (https://waza-ari.nirs.qst.go.jp). Materials and Methods: We collected actual patient information and CT scan parameters from hospitals and medical facilities with more than 200 beds that perform pediatric CT in the Kyushu region, Japan through a questionnaire survey. To estimate the actual organ dose (brain dose, bone marrow dose, thyroid dose, lens dose), we divided the pediatric population into five age groups (0, 1, 5, 10, 15) based on body size, and inputted CT scan parameters into WAZA-ARI. Results and Discussion: Organ doses for each age group were obtained using WAZA-ARI. The brain dose, thyroid dose, and lens dose were the highest in the Age 0 group among the age groups, and the bone marrow and thyroid doses tended to decrease with increasing age groups. All organ doses showed differences among facilities, and this tendency was remarkable in the young group, especially in the Age 0 group. This study confirmed a difference of more than 10-fold in organ doses depending on the facility and CT scan parameters, even when the same CT device was used in the same age group. Conclusion: This study indicated that organ doses varied widely by age group, and also suggested that CT scan parameters are not optimized for children in some hospitals and medical facilities.