Dual-layer spectral detector computed tomography versus magnetic resonance cholangiopancreatography for biliary stones.

Objective: Dual-layer spectral detector computed tomography (DLCT) can detect noncalcified biliary stones. The diagnostic ability of DLCT for detecting biliary stones may be comparable to that of magnetic resonance cholangiopancreatography (MRCP). This study seeks to compare the diagnostic ability for biliary stones between these two imaging modalities.

Relationship between Homocysteine, Folate, Vitamin B and Physical Performance in the Institutionalized Elderly.

Hyperhomocysteinemia causes various diseases including cardiovascular disease, osteoporotic fracture and dementia. Although there have been reports that hyperhomocysteinemia decreases physical performance, findings are inconsistent on the association of homocysteine, folate, vitamin B and physical performance. Considering that lower physical performance increases the risk of fall and fracture in the elderly, the effect of nutritional status on physical function must be clarified.

Low contrast material dose coronary computed tomographic angiography using a dual-layer spectral detector system in patients at risk for contrast-induced nephropathy.

Objective:: To evaluate the effects of virtual monochromatic imaging (VMI) using dual-layer spectral detector CT on the image quality of coronary CT angiography (CCTA) acquired by using a low contrast material (CM) dose.

Methods:: We used a VMI 50keV protocol with a 50%  CM dose (140  mgI kg) to scan 30 patients with renal insufficiency and a 120 kVp with the standard CM dose (280  mgI kg) to scan 30 controls without renal insufficiency. Quantitative parameters, including CT attenuation, image noise, and contrast-to-noise ratio (CNR), were measured.

Reduced iodinated contrast media for abdominal imaging by dual-layer spectral detector computed tomography for patients with kidney disease.

Contrast-enhanced computed tomography using iodinated contrast media is useful for diagnosis of gastrointestinal diseases. However, contrast-induced nephropathy remains problematic for kidney diseases patients. Although current guidelines recommended the use of a minimal dose of contrast media necessary to obtain adequate images for diagnosis, obtaining adequate images with sufficient contrast enhancement is difficult with conventional computed tomography using reduced contrast media.

Usefulness and limitations of dual-layer spectral detector computed tomography for diagnosing biliary stones not detected by conventional computed tomography: a report of three cases.

Computed tomography (CT) is useful for diagnosing biliary stones. However, the presence of stones not detected by conventional CT, such as iso-dense stones with CT numbers similar to those of bile or small stones, is problematic. Although conventional CT provides only 120-kVp images corresponding to CT numbers at approximately 70 keV, dual-layer spectral detector CT uses one X-ray source and dual-layer detectors to collect low- and high-energy data simultaneously; retrospective spectral analysis, including virtual monochromatic images with photon energy levels of 40-200 keV, material decomposition images, and spectral curves, can be immediately performed on demand.

Comparison of lower leg muscle strength and grip strength for diagnosing slower gait speed in the elderly.

Objectives: Sarcopenia, decreased muscle volume and muscle weakness in the elderly is a serious risk of various adverse outcomes. Current diagnostic procedure for sarcopenia includes gait speed, grip strength, and percentage of skeletal muscle volume. However, lower leg muscle strength decreases much faster than grasp power, and we have evaluated the usefulness of its measurement using a recently developed instrument (Locomoscan).

The Influence of Iterative Reconstruction on Coronary Artery Calcium Scoring-Phantom and Clinical Studies.

Rationale And Objectives: We compared the effect of iterative model reconstruction (IMR), filtered back projection (FBP), and hybrid iterative reconstruction (HIR) on coronary artery calcium (CAC) scoring.

Materials And Methods: CAC scans of 30 consecutive patients (18 men and 12 women, age 70.1 ± 12.

Effect of iterative reconstruction on variability and reproducibility of epicardial fat volume quantification by cardiac CT.

Background: The epicardial fat volume (EFV) measured by cardiac CT has emerged as an important parameter for understanding the pathophysiology of coronary atherosclerosis.

Objective: We investigated the variability and reproducibility of EFV measurements and evaluated the effect of model-based type iterative reconstruction (M-IR) on measurement results.

Methods: Non-contrast cardiac CT data (tube voltage 120-kVp, tube current time product 32 mAs) of 30 consecutive patients were reconstructed with filtered back projection (FBP), hybrid type iterative reconstruction (H-IR), and M-IR using a slice thickness of 3.

Improved image quality at 256-slice coronary CT angiography in patients with a high heart rate and coronary artery disease: comparison with 64-slice CT imaging.

Background: The 256-slice computed tomography (CT) scanners with wider detector coverage and faster gantry rotation speed are now available. The performance of scanners that feature a rotation speed of 270 ms at coronary CT angiography (CCTA) has not been evaluated in patients with a higher heart rate.

Purpose: To evaluate the image quality of 256-slice CT with faster gantry rotation speed in patients undergoing CCTA.

Extracapsular extension of prostate cancer: diagnostic value of combined multiparametric magnetic resonance imaging and isovoxel 3-dimensional T2-weighted imaging at 1.5 T.

Objective: The objective of this study was to assess whether adding isovoxel 3-dimensional T2-weighted imaging (volume isotropic T2-weighted acquisition [VISTA]) to multiparametric magnetic resonance imaging (mp-MRI) improves the ability to diagnose the extracapsular extension (ECE) of prostate cancer.

Methods: Two radiologists independently evaluated ECE on images acquired with mp-MRI only (method A) and mp-MRI plus VISTA (method B) in 50 men who had undergone prostatectomy. We also compared the signal-to-noise ratio of the tumor on T2WI and VISTA scans.

Onset of buccal pumping in catshark embryos: how breathing develops in the egg capsule.

Respiration in fishes involves buccal pumping, which is characterized by the generation of nearly continuous water flow over the gills because of the rhythmic expansion/compression of the pharyngeal cavity. This mechanism is achieved by the functions of the vascular, skeletal, and muscular systems. However, the process by which the embryo establishes the mechanism remains a mystery.

Clinical impact of 3-dimensional balanced turbo-field-echo magnetic resonance cholangiopancreatography at 3 T: prospective intraindividual comparison with 3-dimensional turbo-spin-echo magnetic resonance cholangiopancreatography.

Objective: The objective of this study was to evaluate the clinical utility of 3-dimensional (3D) balanced turbo-field-echo (BTFE) magnetic resonance cholangiopancreatography (MRCP) with gate and track acquisition at 3 T.

Methods: Using a 3-T unit, we subjected 52 consecutive patients to 3D BTFE MRCP with the navigator-gated technique and 3D turbo-spin-echo volume isotropic T2-weighted acquisition (VISTA) MRCP with the navigator-triggered technique. Two radiologists independently rated the image quality and visibility of the right and left hepatic duct, cystic duct, common bile duct, gallbladder, and main pancreatic duct using a 4-point scale.

Improved coronary in-stent visualization using a combined high-resolution kernel and a hybrid iterative reconstruction technique at 256-slice cardiac CT-Pilot study.

Objectives: To investigate the diagnostic performance of 256-slice cardiac CT for the evaluation of the in-stent lumen by using a hybrid iterative reconstruction (HIR) algorithm combined with a high-resolution kernel.

Methods: This study included 28 patients with 28 stents who underwent cardiac CT. Three different reconstruction images were obtained with: (1) a standard filtered back projection (FBP) algorithm with a standard cardiac kernel (CB), (2) an FBP algorithm with a high-resolution cardiac kernel (CD), and (3) an HIR algorithm with the CD kernel.

Indirect computed tomography venography with a low-tube-voltage technique: reduction in the radiation and contrast material dose--a prospective randomized study.

Objective: The objective of the study was to investigate the effects of low-tube-voltage computed tomography (CT) venography on qualitative and quantitative image parameters and the radiation dose.

Methods: Eighty-eight studies on 84 patients underwent pelvic and lower-extremity CT venography under protocol A (standard 120 kV with 150 mL of contrast material, n = 44) or protocol B (80 kV with 100 mL of contrast material, n = 44) on a 64-detector CT scanner. We compared the dose length product in the 2 protocols.