• Imaging Science in Dentistry
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• v.52 no.2
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• pp.141-153
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• 2022

Purpose: This study aimed to identify the prevalence and extension of the anterior loop (AL) of the mental nerve in different populations and according to different cone-beam computed tomography (CBCT) imaging settings. Materials and Methods: Medline/PubMed, Embase, Scopus, Web of Science, and ProQuest were searched. The main inclusion criterion was ALs evaluated in CBCT images. The quality of studies was assessed with the Joanna Briggs Institute risk of bias checklist. Subgroup analyses were conducted for sex, side, continent, voxel size, field of view, and type of CBCT-reconstruction images with a random-effects model. Results: Sixty-three studies with 13,743 participants (27,075 hemimandibles) were included. An AL was found in 40.6% (95% CI: 32.8%-48.9%, P<0.05) of participants and 36.0% (95% CI: 27.5%-45.5%, P<0.05) of hemimandibles, in 34.9% (95% CI: 25.1%-46.2%, P<0.05) of males and 34.5% (95% CI: 23.5%-47.4%, P<0.05) of females. The average length of ALs was 2.39 mm (95% CI: 2.07-2.70 mm, P<0.05). Their extension was 2.13 mm (95% CI: 1.54-2.73 mm, P<0.05) in males and 1.85 mm (95% CI: 1.35-2.36 mm, P<0.05) in females. Significant differences were observed regarding the prevalence and length of ALs among continents and for its measured length on different CBCT-reconstruction images, but not between other subgroups. Conclusion: AL was a relatively common finding. The voxel size and fields of view of CBCT devices were adequate for assessing AL; however, a 2-mm safety margin from anatomical structures(such as the AL) could be recommended to be considered when using CBCT imaging.

• Investigative Magnetic Resonance Imaging
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• v.23 no.4
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• pp.296-315
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• 2019

Cardiac magnetic resonance (CMR) imaging is widely used in many areas of cardiovascular disease assessment. This is a practical, standard CMR protocol for beginners that is designed to be easy to follow and implement. This protocol guideline is based on previously reported CMR guidelines and includes sequence terminology used by vendors, essential MR physics, imaging planes, field strength considerations, MRI-conditional devices, drugs for stress tests, various CMR modules, and disease/symptom-based protocols based on a survey of cardiologists and various appropriate-use criteria. It will be of considerable help in planning and implementing tests. In addressing CMR usage and creating this protocol guideline, we particularly tried to include useful tips to overcome various practical issues and improve CMR imaging. We hope that this document will continue to standardize and simplify a patient-based approach to clinical CMR and contribute to the promotion of public health.

• Journal of the Korean Society of Radiology
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• v.85 no.4
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• pp.693-704
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• 2024

Artificial intelligence (AI) technology is actively being applied for the interpretation of medical imaging, such as chest X-rays. AI-based software medical devices, which automatically detect various types of abnormal findings in chest X-ray images to assist physicians in their interpretation, are actively being commercialized and clinically implemented in Korea. Several important issues need to be considered for AI-based detection assistant tools to be applied in clinical practice: the evaluation of performance and efficacy prior to implementation; the determination of the target application, range, and method of delivering results; and monitoring after implementation and legal liability issues. Appropriate decision making regarding these devices based on the situation in each institution is necessary. Radiologists must be engaged as medical assessment experts using the software for these devices as well as in medical image interpretation to ensure the safe and efficient implementation and operation of AI-based detection assistant tools.

• Progress in Medical Physics
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• v.20 no.2
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• pp.51-61
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• 2009

A Compton camera, which is based on the geometrical interpretation of Compton scattering, is a very promising gamma-ray imaging device considering its several advantages over the conventional gamma-ray imaging devices: high imaging sensitivity, 3-D imaging capability from a fixed position, multi-tracing functionality, and almost no limitation in photon energy. In the present study, a Monte Carlo-based, user-friendly Compton imaging simulator was developed in the form of a graphical user interface (GUI) based on Geant4 and $MATLAB^{TM}$. The simulator was tested against the experimental result of the double-scattering Compton camera, which is under development at Hanyang University in Korea. The imaging resolution of the simulated Compton image well agreed with that of the measured image. The imaging sensitivity of the measured data was 2~3 times higher than that of the simulated data, which is due to the fact that the measured data contains the random coincidence events. The performance of a stacking-structure type Compton camera was evaluated by using the simulator. The result shows that the Compton camera shows its highest performance when it uses 4 layers of scatterer detectors.

• Journal of radiological science and technology
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• v.42 no.5
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• pp.365-371
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• 2019

We have developed and applied a diagnostic Multi-Leaf Collimator (MLC) to optimized the X-ray field in medical imaging and the usefulness evaluated through the fusion of infrared image and X-ray image acquired by infrared camera. The hand and skull radiography with multi-leaf collimator(MLC) showed significant area dose reductions of 22.9% and 31.3% compared to ARC and leakage dose was compliant with KS A 4732. Also scattering doses of 50 cm and 100 cm showed a significant decrease to confirm the usefulness of MLC. It was confirmed that the fusion of infrared images with an adjustable degree of transparency was possible in the X-ray images. Therefore, fusion of anatomical information with physiological convergence is expected to contribute and improvement of diagnostic ability. In addition, the feasibility of convergence X-ray imaging and DITI devices and the possibility of driving MLC with infrared images were confirmed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1209-1214
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• 2011

Photoacoustics has been broadly studied in biomedicine, for both human and small animal tissues. Photoacoustics uniquely combines the absorption contrast of light or radio frequency waves with ultrasound resolution. Moreover, it is non-ionizing and non-invasive, and is the fastest growing new biomedical method, with clinical applications on the way. This paper provides a brief recap of recent developments in photoacoustics in biomedicine, from basic principles to applications. The emphasized areas include the new imaging modalities as well as translational research topics. A primary PA application in biomedicine is photoacoustic tomography (PAT). The past decade has seen fast developments in both theoretical reconstruction algorithms and innovative imaging techniques, and PAT has been implemented in imaging different tissues, from centimeter-large breast tumors to several micrometer-large single red blood cels (RBC). PAT now provides structural, functional and molecular imaging. Overall, PA techniques for biomedicine are maturing. They have been widely used to study both animal and human tissues. Recently, more and more research focuses on clinical applications. Commercialized PA systems are expected to be available in the near future, and wide clinical PA applications are foreseen.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.389-394
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• 2015

There is a progressive development in the medical imaging technology, especially of descriptive capability for anatomical structure of human body thanks to advancement of information technology and medical devices. But however maintenance of correct posture is essential for the medical imaging checkup on the shoulder joint requiring rotation of the upper limb due to the complexity of human body. In the cases of MRI examination, long duration and fixed posture are critical, as failure to comply with them leads to minimal possibility of reproducibility only with the efforts of the examiner and will of the patient. Thus, this study aimed to develop an auxiliary device that enables rotation of the upper limb as well as fixing it at quantitative angles for medical imaging examination capable of providing diagnostic values. An auxiliary device has been developed based on the results of precedent studies, by designing a 3D model with the CATIA software, an engineering application, and producing it with the 3D printer. The printer is Objet350 Connex from Stratasys, and acrylonitrile- butadiene-styrene(ABS) is used as the material of the device. Dimensions are $120{\times}150{\times}190mm$, with the inner diameter of the handle being 125.9 mm. The auxiliary device has 4 components including the body (outside), handle (inside), fixture terminal and the connection part. The body and handle have the gap of 2.1 mm for smooth rotation, while the 360 degree of scales have been etched on the handle so that the angle required for observation may be recorded per patient for traceability and dual examination.

• Journal of Biomedical Engineering Research
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• v.8 no.2
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• pp.117-117
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• 1987

The medical image processing system is intended for a diverse set of users in the medical Imaging Parts. This system consists of a 640 Kbyte IBM-PC/AT with 30 Mbyte hard disk, special purpose image processor with video input devices and display monitor. Image may be recorded and processed in real time at sampling rate up to 10 MHz. This system provides a wide range of image enhancement processing facilities via a menu-driven software packages. These facilities include point by point processing, image averaging, convolution filter and subtraction.

• Journal of Oriental Neuropsychiatry
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• v.31 no.2
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• pp.89-99
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• 2020

Objectives: The purpose of this study was to identify the needs of bio-signal devices for the diagnosis, assessment, and analysis of neurocognitive disorder in Korean medicine (KM) hospitals and clinics. Methods: A questionnaire was developed to survey the current status of medical device use, and diagnosis and interventions for patients with cognitive disorders in KM hospitals and clinics. November 11~December 2, 2019, 114 responses (71.9% completed) were collected by internet-based questionnaires from the members of the Korean society of Oriental Neuropsychiatry. Results: The clinical requests were in the descending order of hematology analyzer, ultrasound imaging system, and electroencephalography among the 15 most commonly used devices of which research would support for their clinical usability. The biosignal-based devices showed the highest research demands for patients with mild cognitive impairment rather than more severe stages of cognitive impairment. Prevention rather than diagnosis, or several treatment regimens was the strongest clinical area of the KM for patients with neurodegenerative cognitive impairment. Many responded that five to 10 minutes of test duration and 20,000 won to 30,000 won of cost would be appropriated for a new device to be developed. Conclusions: There were strong demands for the development of bio-signal devices for neurocognitive disorders among the KM doctors. Specifically, it showed high needs for the technology that can be used in the prevention area of cognitive disorders. Additionally, new medical devices to assess cognitive functions and to obtain KM pattern-related information were the high needs.

• Current Optics and Photonics
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• v.6 no.2
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• pp.151-160
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• 2022

Fundus images can reflect ocular diseases and systemic diseases such as glaucoma, diabetes mellitus, and hypertension. Thus, research on fundus-detection equipment is of great importance. The fundus camera has been widely used as a kind of noninvasive detection equipment. Most existing devices can only obtain two-dimensional (2D) retinal-image information, yet the fundus of the human eye also has spectral characteristics. The fundus has many pigments, and their different distributions in the eye lead to dissimilar tissue penetration for light waves, which can reflect the corresponding fundus structure. To obtain more abundant information and improve the detection level of equipment, a snapshot nonmydriatic fundus imaging spectral system, including fundus-imaging spectrometer and illumination system, is studied in this paper. The system uses a microlens array to realize snapshot technology; information can be obtained from only a single exposure. The system does not need to dilate the pupil. Hence, the operation is simple, which reduces its influence on the detected object. The system works in the visible and near-infrared bands (550-800 nm), with a volume less than 400 mm × 120 mm × 75 mm and a spectral resolution better than 6 nm.