The aim of this study was to assess the accuracy, reliability, and cerebral microbleed (CMB) detection performance of 2-minute quantitative susceptibility mapping (QSM) from 3-dimensional echo-planar imaging (3D-EPI).Gadolinium phantom study was conducted using 3D-EPI, single-echo time (TE), and multi-TE gradient-recalled echo (GRE) sequences on two 3-T magnetic resonance (MR) scanners to assess the accuracy between measured and theoretical susceptibility values. The institutional review board approved this prospective study, and 40 healthy volunteers were enrolled with written consent between April 2018 and October 2019. Each underwent 3D-EPI, single-TE, and multi-TE GRE sequences consecutively on one 3-T MR scanner, and QSMs were calculated to assess the reliability of 3D-EPI QSM. Intraclass correlation coefficient (ICC), linear regression, and Bland-Altman plots were calculated. Patients with CMB who underwent both 3D-EPI and GRE QSM scans were retrospectively enrolled. Two radiologists evaluated images independently, and Cohen κ coefficients were calculated to compare CMB detection performance.Phantom study showed excellent validity of 3D-EPI QSM on both MR scanners: Skyra, R2 = 0.996, P < 0.001, ICC = 0.997, mean difference, -2 ppb (95% confidence interval [CI], -45 to 40 ppb); Prisma, R2 = 0.992, P < 0.001, ICC = 0.988, mean difference, 15 ppb (95% CI, -67 to 97 ppb). A human study of 40 healthy volunteers (59 ± 13 years, 25 women) showed excellent reliability with 3D-EPI QSM for both single-TE and multi-TE GRE (R2 = 0.981, P < 0.001, ICC = 0.988; R2 = 0.983, P < 0.001, ICC = 0.990, respectively), supported by a Bland-Altman mean difference of 4 ppb (95% CI, -15 to 23 ppb) for single-TE GRE and 3 ppb (95% CI, -15 to 20 ppb) for multi-TE GRE. The CMB detection performance evaluation from 38 patients (51 ± 20 years, 20 women) showed almost perfect agreement between 3D-EPI and GRE QSM for both raters (κ = 0.923 and 0.942, P < 0.001).Faster QSM from 3D-EPI demonstrated excellent accuracy, reliability, and CMB detection performance.
Since it is necessary to realize virtual organizations in networks, to develop systems to be used for realizing various kinds of cooperation support among users is very important as a basis of virtual organizations. VIEW Media has been developed for such a purpose, utilizing CSCW (Computer Supported Cooperative Work) and database technologies. By introducing the concept of environment, VIEW Media supports flexible information sharing mechanisms. The major purpose of this paper is to show the advantages of the environment model for flexible sharing. Several well-known models are compared and then a representative model, the room model, is selected for comparison to develop the same application. Since the environment model is more general than the room model, we decided to develop "debate systems" which are rather complicated yet can be realized by both models. Debate systems can be regarded as generalization of conference systems and thus we believe the comparison is appropriate. By real usage of debate systems developed by VIEW Media (the environment model) and TeamWave (the room model), the environment model is shown to be suitable for such applications.
We report a 53-year-old man presenting with a sore throat, chest pain, and dysphagia. We diagnosed phlegmonous esophagogastritis. Contrast-enhanced CT revealed diffuse thickening of the esophagus and stomach wall with an intramural low-density area surrounded by peripheral rim enhancement. On postcontrast CT, the cranial side of the abscess was continuous with the pharyngeal submucosa, suggesting the source of the inflammation. Upper gastrointestinal endoscopy demonstrated purulent material draining from esophageal and gastric ulcers. Acute phlegmonous esophagogastritis is a rare disorder characterized by diffuse infiltration of inflammatory cells to the submucosa of the esophagus and stomach. Detecting a connection of esophageal lesion with the pharynx may lead to a better clinical assessment of the disease.
Abstract Objective To compare the absolute values and repeatability of magnetic resonance fingerprinting (MRF) with 3000 and 1500 echoes/slice acquired in 41 s and 20 s (MRF3k and MRF1.5k, respectively). Materials and methods MRF3k and MRF1.5k scans based on fast imaging with steady precession (FISP) were conducted using a 3 T scanner. Inter-scan agreement and intra-scan repeatability were investigated in 41 and 28 subjects, respectively. Region-of-interest (ROI) analysis was conducted on T1 values of MRF3k by two raters, and their agreement was evaluated using intraclass correlation coefficients (ICCs). Between MRF3k and MRF1.5k, differences in T1 and T2 values and inter-measurement correlation coefficients (CCs) were investigated. Intra-measurement repeatability was evaluated using coefficients of variation (CVs). A p value < 0.05 was considered statistically significant. Results The ICCs of ROI measurements were 0.77–0.96. Differences were observed between the two MRF scans, but the CCs of the overall ROIs were 0.99 and 0.97 for the T1 and T2 values, respectively. The mean and median CVs of repeatability were equal to or less than 1.58% and 3.13% in each of the ROIs for T1 and T2, respectively; there were some significant differences between MRF3k and MRF1.5k, but they were small, measuring less than 1%. Discussion Both MRF3k and MRF1.5k had high repeatability, and a strong to very strong correlation was observed, with a trend toward slightly higher values in MRF1.5k.
Background Hypothalamic–pituitary–thyroid (HPT) maturation has not been extensively evaluated using neonatal MRI, even though both structures are visualized on MRI. Hypothesis That signal intensity and volume of pituitary and thyroid (T) glands on MRI in neonates may be interrelated. Study Type Retrospective. Subjects In all, 102 participants. Field Strength/Sequence 3.0T, T 1 ‐weighted pointwise encoding time reduction with radial acquisition (PETRA). Assessment The volume of interest of the anterior pituitary (AP), posterior pituitary (PP), and T on MRI were defined on T 1 ‐PETRA by two radiologists, and volumes of AP (AP_vol) and thyroid (T_vol) were calculated. Gestational age (GA), chronological age (CA), GA+CA, birth weight (BW), and thyroid function were recorded. Mean and maximum signal intensities of AP, PP, and T were normalized using signals from the pons and spinal cord as follows: signal ratio of anterior pituitary/pons (AP/pons), signal ratio of posterior pituitary/pons (PP/pons), and signal ratio of thyroid/cord (T/cord) T/cord, respectively. Statistical Tests Correlations between signal intensity and volume measures and GA, CA, GA+CA, and BW were assessed using Pearson's correlation coefficient or Spearman's rank correlation coefficient. Thyroid function analysis and T mean /cord, T max /cord, and T_vol were evaluated using the Steel–Dwass test. Results AP mean /pons correlated positively with GA (ρ = 0.62, P < 0.001) and BW (ρ = 0.74, P < 0.001), and negatively with CA (ρ = −0.86, P < 0.001) and GA+CA (ρ = −0.46, P < 0.001). PP mean /pons correlated positively with GA (ρ = 0.49, P < 0.001) and BW (ρ = 0.63, P < 0.001), and negatively with CA (ρ = −0.70, P < 0.001) and GA+CA ( r = −0.38, P < 0.001). T mean /cord correlated positively with GA (ρ = 0.48, P < 0.001) and BW (ρ = 0.55, P < 0.001), and negatively with CA (ρ = −0.59, P < 0.001) and GA+CA (ρ = −0.22, P = 0.03). AP_vol correlated positively with GA (ρ = 0.68, P < 0.001) and BW (ρ = 0.73, P < 0.001), and negatively with CA (ρ = −0.72, P < 0.001). T_vol correlated positively with GA (ρ = 0.50, P < 0.001) and BW (ρ = 0.61, P < 0.001), and negatively with CA (ρ = −0.54, P < 0.001). AP mean /pons correlated positively with T mean /cord (ρ = 0.61, P < 0.001). Data Conclusion Signal and volume of pituitary and thyroid glands correlated positively with GA and BW, and negatively with CA in neonates. Level of Evidence 4 Technical Efficacy Stage 5
Journal Article Oligomeric Structures Required for Complement Activation of Serum Mannan- Binding Proteins Get access Yasunori Yokota, Yasunori Yokota Department of Biological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto UniversitySakyo-ku, Kyoto 606 Search for other works by this author on: Oxford Academic PubMed Google Scholar Tohru Arai, Tohru Arai Department of Biological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto UniversitySakyo-ku, Kyoto 606 Search for other works by this author on: Oxford Academic PubMed Google Scholar Toshisuke Kawasaki Toshisuke Kawasaki Department of Biological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto UniversitySakyo-ku, Kyoto 606 Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Biochemistry, Volume 117, Issue 2, February 1995, Pages 414–419, https://doi.org/10.1093/jb/117.2.414 Published: 01 February 1995 Article history Received: 26 September 1994 Published: 01 February 1995
