Effect of Contrast Level and Image Format on a Deep Learning Algorithm for the Detection of Pneumothorax with Chest Radiography.

Under the black-box nature in the deep learning model, it is uncertain how the change in contrast level and format affects the performance. We aimed to investigate the effect of contrast level and image format on the effectiveness of deep learning for diagnosing pneumothorax on chest radiographs. We collected 3316 images (1016 pneumothorax and 2300 normal images), and all images were set to the standard contrast level (100%) and stored in the Digital Imaging and Communication in Medicine and Joint Photographic Experts Group (JPEG) formats.

Therapeutic effect of local photothermal heating of gold nanoparticle-coated self-expandable metallic stents for suppressing granulation tissue formation in the mouse colon.

Purpose: To investigate the therapeutic effect of local photothermal (PT) heating on suppression of stent-induced granulation tissue formation in mouse colon.

Materials And Methods: A gold nanoparticle (GNP)-coated self-expandable metallic stent (SEMS) was prepared using a two-step synthesis process for local PT heating under near-infrared laser irradiation. Twenty-four mice were randomly divided into two groups of 12 and subjected to SEMS placement in the colon.

Dose-Decreasing Effect of the First Reversed Laser Beam Collimator for C-Arm Type Angiographic Equipment.

This is a study on the dose-decreasing effect of the first reversed laser beam collimator (RLBC) for C-arm type angiographic equipment. A laser beam was located at the center of each plane at an oblique angle to the angiographic equipment detector. A field of view, which could be seen with the naked eye, was made by focusing the laser beam in the direction of the X-ray source.

RADIATION DOSE FOR PEDIATRIC AND YOUNG ADULT CT: A SURVEY TO ESTABLISH AGE-BASED REFERENCE LEVELS OF 2015-2016 IN KOREA.

To assess the doses delivered to pediatric patients during computed tomography (CT) examinations of the brain, chest, high-resolution lung and abdomen, and to establish diagnostic reference levels (DRLs) for various age groups in Korea. Dose survey was done to the 19 hospitals performing CT on children, addressing the scan parameters, volume CT dose index (CTDIvol) and dose length product (DLP). Per five age group (0, 1, 2-5, 6-10, 11-17 y of age), the proposed DRLs for brain, chest, high-resolution lung and abdomen CT are, respectively, in terms of CTDIvol: 18, 23, 26, 31, 36 mGy; 2, 3, 4, 6, 8 mGy; 2, 3, 4, 5, 7 mGy; 3, 4, 5, 6, 9 mGy; and in terms of DLP: 260, 350, 420, 500, 620 mGy•cm; 50, 80, 100, 170, 340 mGy•cm; 30, 40, 60, 90, 280 mGy•cm; 70, 80, 200, 300, 500 mGy•cm.

Patient dose for computed tomography examination: dose reference levels and effective doses based on a national survey of 2013 in Korea.

14,620 sets of patient dose data were obtained for 31 different models of computed tomography (CT) equipment (total 73) with 18 types of CT examination in Korea. Specific diagnostic reference levels (DRLs) for this study in terms of third quartile volumetric CT dose index in mGy [and dose-length product (DLP) in mGy.cm] are as follows: head, 53 (910); neck, 20 (770); chest, 14 (710); abdomen, 14 (1000); stomach, 14 (1000); liver, 14 (1700); pancreas, 14 (1700); kidney, 14 (2100); cervical spine, 30 (600); lumbar spine, 25 (760); hip, 17 (600); cardiac CT angiography, 45 (1250); head CT angiography, 43 (1900); liver CT angiography, 14 (1400) and thoraco-abdominal CT angiography, 16 (2000).

Effectiveness of a silicone device for foot MRI in order to obtain homogeneous fat suppression images.

Background: Incomplete fat suppression induced by magnetic field inhomogeneity is difficult to compensate for with hardware magnetic-field shimming.

Purpose: To evaluate the effectiveness of a silicone device used to obtain homogeneous fat suppression during 3T magnetic resonance imaging (MRI) scans of the foot.

Material And Methods: Thirty-eight healthy volunteers were enrolled and examined twice, before (group A) and after (group B) the application of a silicone device.

Radiation exposure in multidetector CT: dose comparison between late 1990s and early 2010s in Korea.

The effective dose under ordinary clinical computed tomography (CT) protocols using three kinds of 64-channel and a 40-channel CT ranged from 0.6 to 15.5 mSv in early 2010s.

Performance evaluation of biosignal measurement at the wheelchair system.

The purpose of this study is to measure both ECG and BCG(Ballistocariograph) signal of a subject on moving or resting wheelchair and detect the heart rate and respiratory rate and transmit an event message to remote server on emergent situation. To acquire ECG and BCG data, amplifier circuits were composed to be suitable for their characteristics. 3-axial accelerometer was built in the developed device to measure the mechanical noise that can be generated on moving wheelchair.

Wheelchair type biomedical system with event-recorder function.

The present study is about a biometric system for a wheelchair, which can measure both bio-signal (ECG-Electrocardiogram, BCG-Ballistocardiogram) and kinetic signal (acceleration) simultaneously and send the data to a remote medical server. The equipment was developed with the object of building a system that measures the bio-signal and kinetic signal of a subject who is moving or at rest on a wheelchair and transmits the measured signals to a remote server through a CDMA (Code Division Multiple Access) network. The equipment is composed of body area network and remote medical server.