• Progress in Medical Physics
• /
• v.20 no.2
• /
• pp.62-71
• /
• 2009

Recently, optical coherence tomography (OCT) has demonstrated considerable promise for the noninvasive assessment of biological tissues. However, OCT images difficult to analyze due to speckle noise. In this paper, we tested various image processing techniques for speckle removal of human and rabbit cartilage OCT images. Also, we distinguished the images which get with methods of image segmentation for OCT images, and found the most suitable method for segmenting an image. And, we selected image segmentation suitable for OCT before image reconstruction. OCT was a weak point to system design and image processing. It was a limit owing to measure small a distance and depth size. So, good edge matching algorithms are important for image reconstruction. This paper presents such an algorithm, the chamfer matching algorithm. It is made of background for 3D image reconstruction. The purpose of this paper is to describe good image processing techniques for speckle removal, image segmentation, and the 3D reconstruction of cartilage OCT images.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2008.05a
• /
• pp.131-134
• /
• 2008

한의학의 대중화와 세계화를 위해서는 타 의학과의 차별화와 진단의 객관성 확보가 매우 중요하며 이를 위해서는 한의학의 독창적인 의료체계인 사상의학을 통해 차별화를 이루고 또한 객관성 확보를 위해 IT 공학기술과 연계하여 진단기술을 개발한다면 효율적일 것으로 예상한다. 본 논문에서는 사상의학의 체질 분류를 목적으로 하여 체질 분류법 중 용모사기론을 기반으로 한 안면 영상을 통한 사상체질 분류시스템을 개발하기위해 20대 여성을 대상으로 안면 영상을 수집하고 피실험자에 대한 체질분류 작업을 진행하여 안면 요소와 체질 간의 상관관계를 분석하여 체질별 차이를 나타내는 항목을 설정하고 이에 대한 분석을 실험을 통해 수행하고자 한다.

• Progress in Medical Physics
• /
• v.14 no.3
• /
• pp.196-202
• /
• 2003

In 3-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT), many studies on reducing setup error have been conducted in order to focus the irradiation on the tumors while sparing normal tissues as much as possible. As one of these efforts, we developed an image enhancement and registration tool for simulators and portal images that analyze setup errors in a quantitative manner. For setup verification, we used simulator (films and EC-L films (Kodak, USA) as portal images. In addition, digital-captured images during simulation, and digitally-reconstructed radiographs (DRR) can be used as reference images in the software, which is coded using IDL5.4 (Research Systems Inc., USA). To improve the poor contrast of portal images, histogram-equalization, and adaptive histogram equalization, CLAHE (contrast limited adaptive histogram equalization) was implemented in the software. For image registration between simulator and portal images, contours drawn on the simulator image were transferred into the portal image, and then aligned onto the same anatomical structures on the portal image. In conclusion, applying CLAHE considerably improved the contrast of portal images and also enabled the analysis of setup errors in a quantitative manner.

• Journal of the Korean Society of Radiology
• /
• v.84 no.1
• /
• pp.240-252
• /
• 2023

Purpose To assess the effect of deep learning image reconstruction (DLIR) for head CT in pediatric patients. Materials and Methods We collected 126 pediatric head CT images, which were reconstructed using filtered back projection, iterative reconstruction using adaptive statistical iterative reconstruction (ASiR)-V, and all three levels of DLIR (TrueFidelity; GE Healthcare). Each image set group was divided into four subgroups according to the patients' ages. Clinical and dose-related data were reviewed. Quantitative parameters, including the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and qualitative parameters, including noise, gray matter-white matter (GM-WM) differentiation, sharpness, artifact, acceptability, and unfamiliar texture change were evaluated and compared. Results The SNR and CNR of each level in each age group increased among strength levels of DLIR. High-level DLIR showed a significantly improved SNR and CNR (p < 0.05). Sequential reduction of noise, improvement of GM-WM differentiation, and improvement of sharpness was noted among strength levels of DLIR. Those of high-level DLIR showed a similar value as that with ASiR-V. Artifact and acceptability did not show a significant difference among the adapted levels of DLIR. Conclusion Adaptation of high-level DLIR for the pediatric head CT can significantly reduce image noise. Modification is needed while processing artifacts.

• Progress in Medical Physics
• /
• v.6 no.2
• /
• pp.93-101
• /
• 1995

In this paper, we implemented a digital medical image management and a remote monitor display system for a personal computer. The designed system can display up to a 1280${\times}$1024 image which can accomodate eight images with a 256${\times}$256${\times}$8bits. When one of these images is clicked by the mouse, the selected image can be displayed with 256${\times}$256${\times}$8bits or 1024${\times}$1024${\times}$8bits. For the selected image, we can use one of the image processing functions in this system and send it to a remote monitor for the close examinations. To search and store digital images effectively, we constructed and image database management system with the B＋TREE structure. This system can be operated in an IBM-PC 386 or higher and all the function are performed easily with a mouse to provide a user firendly environment.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.04a
• /
• pp.113-116
• /
• 2002

PACS는 의학용 영상 정보의 저장, 판독 및 검색 기능 등의 수행을 통합적으로 처리하는 시스템을 말한다. 그 중 방사선 검사 곁과를 디지털 이미지로 변환하여 대용량 기억장치에 저장시키는데 기에 따른 저장장치의 비용증가와 데이터의 효율적인 관리가 필요하게 되었다. 따라서 의료 영상 데이터의 효율적인 이동을 위한 이미지 저장 시스템의 모듈을 설계하였다.

• The Korean Journal of Nuclear Medicine
• /
• v.20 no.2
• /
• pp.11-17
• /
• 1986

핵의학기기중 scintillation gamma camera의 임상적 유용도는 이미 잘 알려져 왔으며 80년대에 들어와서는 Computer의 도입으로 그이용도가 더욱 확대되어 보유댓수가 급격한 증가를 이루게 되었다. 따라서 이에 대한 정도관리가 필요하게 되었다. 정도관리의 목적은 장비기능의 정상여부를 조기에 발견하여 항상 균등한 질의 영상을 재현하여 보다 정확한 진단을 하는데 있다. 따라서 r-camera의 사용자는 기계의 기능과 성능을 항상 정화하게 파악하여 빠르고 적절한 대책을 세워 양질의 영상을 얻도록 해야한다. 또한 스캔의 결과도 판독자 환자대상군, 검사방법에 따라 천의 예민도 및 특이도가 달라지며 정확도 또한 공간점유병소의 위치, 원인, 병소수의 크기에 따라 달라진다고 하였다. 저자는 이점을 감안하여 대상군, 검사방법 병소위치에 의한 변화를 배제하고 판독자의 검출정확도를 알아보고자 IAEA-RCA 협조를 얻어 IAEA-WHO 제공 간모형 (SALP: simulatied anatomic liver phantom)을 사용하여 국내 16개 병원 핵의학과 staff 20명에게 의뢰하여 얻은 결과와 아시아 8개국의 276명의 결과를 함께 분석하여 다음과 같은 결론을 얻었다. 1) 각개인의 간모형영상의 판독 정확도는 $60%\sim100%$ 사이었고 대부분 90% 내외였다. 2) 아시아 태평양지역의 정확도는 유럽 및 라틴아메리카의 결과와 비슷하였다. 3) 각 나라별의 정확도 결과는 91.1%에서 76.4%를 나타내었다. 4) 스캔너를 사용한 영상의 판독결과와 감마 카메라의 영상판독결과는 차이가 없었다. 5) 정도관리빈도와 정도관리검사방법은 영상판독 정확도의 결과와는 무관 하였다.

• Journal of KIISE:Software and Applications
• /
• v.29 no.11
• /
• pp.803-808
• /
• 2002

This paper describes automatic methods for detection of kidney and kidney tumor on abdominal CT scans. The abdominal CT images were digitalized using a film digitizer and a gray-level threshold method was used to segment the kidney. Based on texture analysis results, which were perform on sample images of kidney tumors, SEED region of kidney tumor was selected as result of homogeneity test. The average and standard deviation, which are representative statistical moments, were used to as an acceptance criteria for homogeneous test. Region growing method was used to segment the kidney tumor from the center pixel of selected SEED region using a gray-level value as an acceptance criteria for homogeneity test. These method were applied to 113 images of 9 cases, which were scanned by GE Hispeed Advantage CT scanner and digitalized by Lumisvs LS-40 film digitizer. The sensitivity was 85% and there was no false-positive results.

• Journal of the Korea Computer Graphics Society
• /
• v.23 no.2
• /
• pp.1-10
• /
• 2017

A variety of filters are applied to improve the quality of noise and low resolution medical images. This is necessary to reduce the radiation dose of the patient and to improve the utilization of the conventional spherical imaging equipment. In the conventional method, it is common to perform filtering using the CPU of the PC. However, it is difficult to produce results in real time by applying various calculations and filters to high-resolution human images using only the CPU performance of a PC used in a hospital. In this paper, we analyze the structure and performance of Intel integrated GPU in CPU and propose a method to perform image filtering using OpenCL parallel processing function. By applying complex filters with high computational complexity to medical images, high quality images can be generated in real time.

• KIPS Transactions on Software and Data Engineering
• /
• v.12 no.6
• /
• pp.243-250
• /
• 2023

Chest X-ray is radiological examination for xeamining the lungs and haert, and is particularly widely used for diagnosing lung disease. Since the quality of these chest X-rays can affect the doctor's diagnosis, the process of evaluating the quality must necessarily go through. This process can involve the subjectivity of radiologists and is manual, so it takes a lot of time and csot. Therefore, in this paper, based on the chest X-ray quality assessment guidelines used in clinical settings, we propose a tool that automates the five quality assessments of artificial shadow, coverage, patient posture, inspiratory level, and permeability. The proposed tool reduces the time and cost required for quality judgment, and can be further utilized in the pre-processing process of selecting high-quality learning data for the development of a learning model for diagnosing chest lesions.