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

• The Journal of Korean Institute of Information Technology
• /
• v.16 no.11
• /
• pp.35-41
• /
• 2018

Electrical impedance tomography (EIT) is a kind of nondestructive testing technique that obtains the internal resistivity distribution from the voltages measured at the electrodes located outside the area of interest. However, an image reconstruction problem in EIT has innate non-linearity and ill-posedness, so that it is difficult to obtain satisfactory reconstructed results. In general, a neural network can efficiently model the input and output relationships of a non-linear system. This paper proposes a method for estimating the position and size of a circular target using a multi-layer neural network. To verify the performance of the proposed method, neural network was trained and various computer simulations were performed and satisfactory performance was verified.

• Journal of International Society for Simulation Surgery
• /
• v.3 no.1
• /
• pp.1-8
• /
• 2016

In the field of Radiology, the Computer Aided Diagnosis is the technology which gives valuable information for surgical purpose. For its importance, several computer vison methods are processed to obtain useful information of images acquired from the imaging devices such as X-ray, Magnetic Resonance Imaging (MRI) and Computed Tomography (CT). These methods, called pattern recognition, extract features from images and feed them to some machine learning algorithm to find out meaningful patterns. Then the learned machine is then used for exploring patterns from unseen images. The radiologist can therefore easily find the information used for surgical planning or diagnosis of a patient through the Computer Aided Diagnosis. In this paper, we present a review on three widely-used methods applied to Computer Aided Diagnosis. The first one is the image processing methods which enhance meaningful information such as edge and remove the noise. Based on the improved image quality, we explain the second method called segmentation which separates the image into a set of regions. The separated regions such as bone, tissue, organs are then delivered to machine learning algorithms to extract representative information. We expect that this paper gives readers basic knowledges of the Computer Aided Diagnosis and intuition about computer vision methods applied in this area.

• Radiation Oncology Journal
• /
• v.32 no.3
• /
• pp.116-124
• /
• 2014

Purpose: To investigate the frequency and clinical significance of detected incidental lung nodules found on computed tomography (CT) simulation images for hepatocellular carcinoma (HCC) using computer-aided diagnosis (CAD) and a physician review. Materials and Methods: Sixty-seven treatment-$na{\ddot{i}}ve$ HCC patients treated with transcatheter arterial chemoembolization and radiotherapy (RT) were included for the study. Portal phase of simulation CT images was used for CAD analysis and a physician review for lung nodule detection. For automated nodule detection, a commercially available CAD system was used. To assess the performance of lung nodule detection for lung metastasis, the sensitivity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. Results: Forty-six patients had incidental nodules detected by CAD with a total of 109 nodules. Only 20 (18.3%) nodules were considered to be significant nodules by a physician review. The number of significant nodules detected by both of CAD or a physician review was 24 in 9 patients. Lung metastases developed in 11 of 46 patients who had any type of nodule. The sensitivities were 58.3% and 100% based on patient number and on the number of nodules, respectively. The NPVs were 91.4% and 100%, respectively. And the PPVs were 77.8% and 91.7%, respectively. Conclusion: Incidental detection of metastatic nodules was not an uncommon event. From our study, CAD could be applied to CT simulation images allowing for an increase in detection of metastatic nodules.

• Journal of Korea Multimedia Society
• /
• v.23 no.8
• /
• pp.903-914
• /
• 2020

In this paper, we present a novel algorithm to generate a 3D model of patient-specific orbital implant, which is finally produced by the 3D printer. Given CT (computed tomography) scan data of the defective orbital wall or floor, we compose the depth image of the defect site by using the depth buffering, which is a computer graphics technology. From the depth image, we compute the 3D surface which fills the broken part by interpolating the points around the broken part. By thickening the 3D surface, we get the 3D volume mesh of the orbital implant. Our algorithm generates the patient-specific orbital implant whose shape is accurately coincident to the broken part of the orbit. It provides the significant time efficiency for manufacturing the implant with supporting high user convenience.

• Journal of applied mathematics & informatics
• /
• v.29 no.3_4
• /
• pp.697-712
• /
• 2011

We present in this paper two versions of a general correction procedure applied to a classical linear iterative method. This gives us the possibility, under certain assumptions, to obtain an extension of it to inconsistent linear least-squares problems. We prove that some well known extended projection type algorithms from image reconstruction in computerized tomography fit into one or the other of these general versions and are derived as particular cases of them. We also present some numerical experiments on two phantoms widely used in image reconstruction literature. The experiments show the importance of these extension procedures, reflected in the quality of reconstructed images.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.195-196
• /
• 2006

Direct laser sintering (DLS) technology for the resign coated sand is one of attractive technologies to produce molds and cores for the foundry industry rapidly and cost effectively. The objective of this case study is to develop casting pilot models using computer simulation technology, DLS RP machine and industrial computed tomography. The proposed casting design was verified by the Z-Cast software in the fields of fluid flow and solidification during the casting process. Casting parts with aluminum alloy using the post-curing treated sand moulds and cores are accurate to dimension and defect free.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06c
• /
• pp.443-446
• /
• 2011

본 연구는 컴퓨터 단층촬영 영상 (CT, Computed Tomography Image)에서 치열궁 (Dental Arch)을 자동으로 검출하는 기법을 제안한다. 제안된 기법에서는 3차원 컴퓨터 단층촬영 영상을 입력 받고 영역 확장법을 이용하여 하악을 분할 한 후 하악의 단면에서 전체적인 치아의 영역을 분할을 한다. 치아의 영역에서 세선화 작업을 거친 후 곡선 정합법을 이용하여 최종 치열궁을 검출한다. 실험 데이터로 두개골 컴퓨터 단층 촬영 데이터를 사용하였다. 본 연구는 치과 영상 데이터로부터 파노라마 영상을 얻는데 이용 될 수 있고 치과 분야의 질병 진단 및 진찰에 이용될 것으로 기대된다.

• The Journal of Korean Academy of Prosthodontics
• /
• v.57 no.1
• /
• pp.66-74
• /
• 2019

Excessive wear causes many complications when untreated, so that accurate diagnosis, analysis and predictive treatment plan should be made, and through evaluation of vertical dimension and stepwise treatment, a stable inter-arch relationship can be set. For the long-term success of implant treatment, ideal position and angle of implant is important, and its importance increases especially in multiple implant cases. Therefore, thorough diagnosis and planning, accurate surgery and prosthodontic procedures are significant. In this case, a 68-year-old male patient with a loss of vertical dimension due to multiple tooth loss and overall tooth wear was planned with systematic analyses from the pre-treatment stage to rehabilitate vertical dimension. Full-mouth fixed rehabilitation with computer tomography guided implant surgery was performed to the newly set vertical dimension and attained satisfactory outcomes both functionally and esthetically.

• Journal of the Korean Society of Radiology
• /
• v.13 no.5
• /
• pp.683-689
• /
• 2019

We are trying to evaluate usefulness of Wide Coverage Volume Axial Mode by comparing and analyzing for exposure doses to patients and video quality extracted from two materials. First material is a computer tomography scanning of paediatric cardiac made by using High Pitch Mode, which is designed for diagnosing Congenital cardiac diseases. Second material is computer tomography scanning of paediatric cardiac made by using Wide Coverage Volume Axial Mode. When we did computer tomography scanning of paediatric cardiac, we used High Pitch Mode and Wide Coverage Volume Axial Mode to 50 patients of each, overall 100 patients. Also, we compared exposure doses to patients using videos got from each protocol. Then we compared video quality by calculating SNR and CNR by setting ROI of each. Not only exposure doses to patients were reduced by 13.07 %, but also SNR and CNR were improved when testing used Wide Coverage Volume Axial Mode rather than using High Pitch Mode. Wide Coverage Volume Axial Mode reduced testing time by using high-speed scanner. Furthermore, we can find out that Wide Coverage Volume Axial Mode is an useful method through improving video quality and reducing exposure doses to patients than using High Pitch Mode from ASiR-V, which is low-dose technology.