• Progress in Medical Physics
• /
• v.32 no.1
• /
• pp.1-17
• /
• 2021

The evolution of X-ray computed tomography (CT) has been based on the discovery of X-rays, the inception of the Radon transform, and the development of X-ray digital data acquisition systems and computer technology. Unlike conventional X-ray imaging (general radiography), CT reconstructs cross-sectional anatomical images of the internal structures according to X-ray attenuation coefficients (approximate tissue density) for almost every region in the body. This article reviews the essential physical principles and technical aspects of the CT scanner, including several notable evolutions in CT technology that resulted in the emergence of helical, multidetector, cone beam, portable, dual-energy, and phase-contrast CT, in integrated imaging modalities, such as positron-emission-tomography-CT and single-photon-emission-computed-tomography-CT, and in clinical applications, including image acquisition parameters, CT angiography, image adjustment, versatile image visualizations, volumetric/surface rendering on a computer workstation, radiation treatment planning, and target localization in radiotherapy. The understanding of CT characteristics will provide more effective and accurate patient care in the fields of diagnostics and radiotherapy, and can lead to the improvement of image quality and the optimization of exposure doses.

• Childhood Kidney Diseases
• /
• v.25 no.1
• /
• pp.14-21
• /
• 2021

Chronic kidney disease, the presence of structural and functional abnormalities in the kidneys, is associated with a lower quality of life and increased morbidity and mortality in children. Genetic etiologies account for a substantial proportion of pediatric chronic kidney disease. With recent advances in genetic testing techniques, an increasing number of genetic causes of kidney disease continue to be found. Genetic testing is recommended in children with steroid-resistant nephrotic syndrome, congenital malformations of the kidney and urinary tract, cystic disease, or kidney disease with extrarenal manifestations. Diagnostic yields differ according to the category of clinical diagnosis and the choice of test. Here, we review the characteristics of genetic testing modalities and the implications of genetic testing in clinical genetic diagnostics.

• Current Optics and Photonics
• /
• v.8 no.4
• /
• pp.327-344
• /
• 2024

Optical phantoms are essential in optical imaging and measurement instruments for performance evaluation, calibration, and quality control. They enable precise measurement of image resolution, accuracy, sensitivity, and contrast, which are crucial for both research and clinical diagnostics. This paper reviews the recent advancements and challenges in phantoms for optical coherence tomography, photoacoustic imaging, digital holographic microscopy, optical diffraction tomography, and oximetry tools. We explore the fundamental principles of each technology, the key factors in phantom development, and the evaluation criteria. Additionally, we discuss the application of phantoms used for enhancing optical-image quality. This investigation includes the development of realistic biological and clinical tissue-mimicking phantoms, emphasizing their role in improving the accuracy and reliability of optical imaging and measurement instruments in biomedical and clinical research.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.2 s.179
• /
• pp.129-137
• /
• 2006

Polymer micro-fluidic devices were fabricated with laser processes. A UV laser and a femto laser were used to machine polymer micro-fluidic structures directly. This laser direct machining process suits the need of rapid prototyping, as in many applications changes from the original design are often required. As examples, two polymer micro-systems were developed: a micro-check valve and a micro diffuser pump. The micro fluidic devices can be applied for many applications such as clinical diagnostics and drug delivery. Advantages and disadvantages using polymers as a material for micro-fluidic applications are discussed.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.113-114
• /
• 2013

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging is a powerful technique for producing chemical images of small biomolecules (ex. metabolites, lipids, peptides) "as received" because of its high molecular specificity, high surface sensitivity, and submicron spatial resolution. In addition, matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) imaging is an essential technique for producing chemical images of large biomolecules (ex. genes and proteins). For this talk, we will show that label-free mass imaging technique can be a platform technology for biomedical studies such as early detection/diagnostics, accurate histologic diagnosis, prediction of clinical outcome, stem cell therapy, biosensors, nanomedicine and drug screening [1-7].

• Childhood Kidney Diseases
• /
• v.28 no.1
• /
• pp.8-15
• /
• 2024

With the rapid evolution of diagnostic tools, particularly next-generation sequencing, the identification of genetic diseases, predominantly those with pediatric-onset, has significantly advanced. However, this progress presents challenges that span from selecting appropriate tests to the final interpretation of results. This review examines various genetic testing methodologies, each with specific indications and characteristics, emphasizing the importance of selecting the appropriate genetic test in clinical practice, taking into account factors like detection range, cost, turnaround time, and specificity of the clinical diagnosis. Interpretation of variants has become more challenging, often requiring further validation and significant resource allocation. Laboratories primarily classify variants based on the American College of Medical Genetics and Genomics and the Association for Clinical Genomic Science guidelines, however, this process has limitations. This review underscores the critical role of clinicians in matching patient phenotypes with reported genes/variants and considering additional factors such as variable expressivity, disease pleiotropy, and incomplete penetrance. These considerations should be aligned with specific gene-disease characteristics and segregation results based on an extended pedigree. In conclusion, this review aims to enhance understanding of the complexities of clinical genetic testing, advocating for a multidisciplinary approach to ensure accurate diagnosis and effective management of rare genetic diseases.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.18 no.2
• /
• pp.121-136
• /
• 2014

Objectives For the excellent differentiation of syndromes, we study on the individual characteristic factor by the inspection of body shape. Methods To the subject of diagnosis special books and diagnostics textbook of korean medicine, we arrange the individual characteristic factor by the four methods of diagnosis. Results The individual characteristic factor analyzed by the inspection of the body shape in the "Huangdineijing 黃帝內經" and "Donguisusebowon 東醫壽世保元" was observed stereotyped. The inspection of the body shape means to diagnose the patient by examining the individual physical conditions of the patient. The body depends on visceral essence to nourish, while the functions of the viscera and the conditions of visceral essence may be reflected by the body. The inspection of individual physical strength and weakness may enable one to know the functions of the viscera and the conditions of ki(氣) and blood. And also the inspection of local regions is used to closely examine some regional areas to obtain necessary clinical data on the individual characteristic factor. Conclusion As the results, the individual characteristic factor by the inspection of body shape is very important item of the four methods of diagnosis(四診) and the differentiation of syndromes(辨證). And therefore the process on four methods of diagnosis and differentiation of syndromesis is necessary to divide the signs of individual characteristic factor and the signs of disease.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.12 no.2
• /
• pp.49-60
• /
• 2008

Objectives: The aim of this study was to investigate correlation of the phlegm-retained fluid, namely Damum(痰飮) and dark circles under eyes. Methods: 2 males and 11 females aged 26-60 years were participated in this study. They were asked the intensity of 29 symptoms related with Damum(痰飮) including dark circle with the questionnaire published by the Journal of the Korea Institute of Oriental Medical Diagnostics. Three skin researchers including OMD graded the dark circles by inspection. We took the pictures around eyes by Facial Stage (Moritex, Japan) and analyzed the skin color by Image-Pro Plus (Media Cybernetics, USA). Results: There was statistically significant correlation between Damum(痰飮) and dark circles measured by self, inspectors and image analysis. Conclusions: In the Oriental Medicine, It is reported that the shadows under eyes are the sign of the retention of fluid, Damum(痰飮). In our study, that shadows, namely dark circles, has correlation with the symptoms of Damum(痰飮). Especially, the correlation between inspected grade and image analysis was very high. According to the above results, it is proved that dark circles under eyes are important diagnostic sign of Damum(痰飮).

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.2
• /
• pp.460-466
• /
• 2006

We wondered whether the mechanisms of antiplatelet aggregation of DJS-WE were through multiple pathways. Danggijakyak-san(DJS) consisting of 6 herbes of Paeoniae Radix, Poria Cocos, Angelicae Sinensis Radix, Cnidii Rhizoma, Atractylodis Macrocephalae Rhizoma and Alismatis Rhizoma, is a crude mixture of a commonly used Korean herbal medicine. The water extract (DJS-WE) of DJS has been known to have an anti-platelet aggregation activity. We have reported that DJS-WE inhibited ADP-induced aggregation as well as arachidonic acid-induced aggregation of human platelet. Clinical studies on the cardiovascular effects of DJS-WE have been done in Korea. The DJS has been used as a remedy for gastrointestinal disorders (abdominal pain, dysentery), headache, amenorrhea, and postpartum hemorrhage. It has also been claimed to have a remarkable central stimulant effect, a transient hypertensive effect, and positive inotropic and chronotropic effects. In this paper, we evaluated the possible mechanisms of the antiplatelet activity of DJS-WE using human platelets. On the other hand, the role of DJS-ethanol extract on the inhibition of platelet aggregation and hemolytic effect have not yet been investigated in detail. We also used the method of activated partial thromboplastin times (APTT) for the first time to study the inhibition on platelet aggregation activity of DJS-ethanol extract. The effect of DJS-WE on hemolysis was also investigated. DJS-WE showed a high hemolysis ability on human blood.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.5
• /
• pp.2805-2809
• /
• 2013

Objective: This study aimed at investigating whether the orphan nuclear receptor NR4A2 is significantly associated with clinicopathologic features and overall survival of patients with nasopharyngeal carcinoma (NPC). Methods: Immunohistochemistry was performed to determine NR4A2 protein expression in 84 NPC tissues and 20 non-cancerous nasopharyngeal (NP) tissues. The prognostic significance of NR4A2 protein expression was evaluated using Cox proportional hazards regression models and Kaplan-Meier survival analysis. Results: We did not find a significant association between total NR4A2 expression and clinicopathological variables in 84 patients with NPC. However, we observed that high cytoplasmic expression of NR4A2 was significantly associated with tumor size (T classification) (P = 0.006), lymph node metastasis (N classification) (P = 0.002) and clinical stage (P = 0.017). Patients with higher cytoplasmic NR4A2 expression had a significantly lower survival rate than those with lower cytoplasmic NR4A2 expression (P = 0.004). Multivariate Cox regression analysis analysis suggested that the level of cytoplasmic NR4A2 expression was an independent prognostic indicator for overall survival of patients with NPC (P = 0.033). Conclusions: High cytoplasmic expression of NR4A2 is a potential unfavorable prognostic factor for patients with NPC.