magnetic resonance scanning
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2021 ◽  
Vol 23 (Supplement_G) ◽  
Author(s):  
Camilla Torlasco ◽  
Silvia Castelletti ◽  
Davide Soranna ◽  
Valentina Volpato ◽  
Stefano Figliozzi ◽  
...  

Abstract Aims Long scanning times impede cardiac magnetic resonance (CMR) clinical uptake. A ‘one-size-fits-all’ shortened, focused protocol [e.g. only function and late-gadolinium enhancement (LGE)] reduces scanning time and costs, but provide less information. We developed two question-driven CMR and stress-CMR protocols, including tailored advanced tissue characterization, and tested their effectiveness in reducing scanning time while retaining the diagnostic performances of standard protocols. Methods and results Eighty-three consecutive patients with cardiomyopathy or ischaemic heart disease underwent the tailored CMR. Each scan consisted of standard cines, LGE imaging, native T1-mapping, and extracellular volume. Fat/oedema modules, right ventricle cine, and in-line quantitative perfusion mapping were performed as clinically required. Workflow was optimized to avoid gaps. See Figure 1 for protocol details. Time target was <30 min for a CMR and <35 min for a stress-CMR. CMR was considered impactful when its results drove changes in diagnosis or management. Advanced tissue characterization was considered impactful when it changed the confidence level in the diagnosis. Images’ quality was assessed. A ‘control group’ of 137 patients was identified among scans performed before February 2020. Compared to standard protocols, the average scan duration dropped by > 30% (CMR: from 42 ± 8 to 28 ± 6min; stress-CMR: from 50 ± 10 to 34 ± 6min, both P < 0.0001). Independent on the protocol, CMR was impactful in ∼60% cases, and advanced tissue characterization was impactful in > 45% of cases. Quality grading was similar between the two protocols. Tailored protocols did not require additional staff. Conclusions Tailored CMR and stress-CMR protocols including advanced tissue characterization are accurate and time-effective for cardiomyopathies and ischaemic heart disease.


2021 ◽  
Vol 11 (4) ◽  
pp. 80-88
Author(s):  
Muzakkir Mohammad Zainol ◽  
Nurul Suhada Ab Rasid ◽  
Mohd Asmadi ◽  
Nor Aishah Saidina Amin

The synthesis of carboxymethyl cellulose (CMC) generally uses isolated crude cellulose with alkaline or acid pretreatment followed by bleaching with sodium chlorite. In this study, the simple [BMIM][Cl] ionic liquid was used as a solvent in the pretreatment process before conduct the bleaching process with hydrogen peroxide (H2O2) to isolate cellulose from empty fruit bunch (EFB) for further synthesis of CMC. The isolated crude EFB cellulose obtained was converted to CMC by adding 30 wt.% NaOH and various concentrations of sodium monochloroacetic acid (SMCA) at 55 °C for 3 h. The effects of SMCA concentration on the degree of substitution (DS) and CMC yield were investigated. The physicochemical properties of the CMC products were characterized using proton nuclear magnetic resonance, scanning electron microscope-energy dispersive spectrometry, X-ray diffraction, and thermogravimetric analysis. Based on the results, CMC was demonstrated to be synthesized using ionic liquid pretreatment with H2O2 bleaching. Carboxymethyl cellulose synthesized in this study showed a high DS of 0.82. The CMC synthesized from EFB cellulose through ionic liquid pretreatment presented good chemical and physical properties as that reported in other studies.


2021 ◽  
Author(s):  
Hiroka Kondo ◽  
Takeshi Ohki ◽  
Shimpei Ogawa ◽  
Yoshiko Bamba ◽  
Yuka Kaneko ◽  
...  

Abstract Background:Lymphangioma is a non-epithelial tumor marked by aggregates of abnormally dilated lymphatics. Mesenteric occurrences account for <1% of all cases, and <0.05% involve the gastrointestinal tract. Most are confined to children, rarely affecting adults. Case presentation:Herein, we describe an elderly Japanese woman with anemia, hypoalbuminemia, and episodic bleeding due to multiple intestinal lymphangiomas. Abdominal computed tomography revealed multiple low-density defects of mesentery, with areas of intermediate (T1 images) or high (T2 images) signal intensity similarly dispersed in magnetic resonance scanning sequences. Single-balloon enteroscopy was undertaken, enabling identification and tattooing of a small intestinal bleeding source. Laparoscopy-assisted resection at this site served to control related hemorrhage, removing a histologically confirmed hemolymphangioma. Having recovered uneventfully, the patient remained stable 2 months postoperatively. Conclusions:Although rare in adults, mesenteric or gastrointestinal lymphangiomas must be considered in a setting of anemia and hypoalbuminemia. Complete resection is advantageous to improve patient symptoms, but limited resection of multiple lesions may be equally effective.


2021 ◽  
Vol 11 (2) ◽  
pp. 497-505
Author(s):  
Dandan Luo ◽  
Daming Qin ◽  
Hong Cheng ◽  
Meng Zhou ◽  
Daoming Zhu ◽  
...  

Multiple myeloma is a refractory malignant disease characterized by clonal hyper proliferation of plasma cells in the bone marrow microenvironment. In recent years, its incidence has gradually increased and it is younger. Magnetic resonance imaging is a medical imaging technology that has developed rapidly in recent years. Its application and promotion have greatly improved the level of medical services and scientific research. It has become one of the most important examination methods for myeloma. Magnetic resonance imaging has a high soft tissue resolution and has a high detection rate for multiple myeloma. However, there are few studies on the MM magnetic resonance scanning protocol, and the initial or follow-up examination methods have not been unified. Therefore, this paper subjectively and objectively evaluates the clinical images of MM patients with multiple sequences of magnetic resonance of different devices, and hopes to provide more advantageous examination methods for clinicians and patients. The experimental results show that magnetic resonance multisequence imaging can be ideal for clinical diagnosis and follow-up of MM patients.


Author(s):  
Sahrai Saeed ◽  
Gu Haotian ◽  
Ronak Rajani ◽  
Phil Chowienczyk ◽  
John Chambers

In aortic stenosis (AS), a left ventricular (LV) ejection fraction (EF) <50% or symptoms are class I indications for aortic valve intervention. However, an EF <50% may be too conservative since subendocardial fibrosis may already have developed. An earlier marker of LV systolic dysfunction is therefore needed and first phase EF (EF1) is a promising new candidate. It is the EF measured over early systole to the point of maximum transaortic blood flow. It may be low in the presence of preserved total LV EF since the heart may compensate by recruiting myosin motors in later systole. The EF1 is inversely related to the grade of AS and directly related to markers of subendocardial fibrosis like late gadolinium enhancement on cardiac magnetic resonance scanning. A reduced EF1 (<25%) predicts adverse clinical events better that total EF and global longitudinal strain. We suggest that it is worth exploring as an indication for surgery in patients with asymptomatic severe AS.


Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 986
Author(s):  
Charlotte Badenhorst ◽  
Cláudia Santos ◽  
Juan Lázaro-Martínez ◽  
Barbara Białecka ◽  
Mihai Cruceru ◽  
...  

Coal ash char concentrates from four countries (Portugal, Poland, Romania, and South Africa) were prepared, characterised, and graphitized under the scope of the Charphite project (Third ERA-MIN Joint Call (2015) on the Sustainable Supply of Raw Materials in Europe). Coal ash chars may be a secondary raw material to produce synthetic graphite and could be an alternative to natural graphite, which is a commodity with a high supply risk. The char concentrates and the graphitized material derived from the char concentrates were characterised using proximate analysis, X-ray fluorescence, X-ray diffraction (structural), Raman microspectroscopy, solid-state nuclear magnetic resonance, scanning electron microscopy, and petrographic analyses to determine if the graphitization of the char was successful, and which char properties enhanced or hindered graphitization. Char concentrates with a lower proportion of anisotropic particles and a higher proportion of mixed porous particles showed greater degrees of graphitization. It is curious to see that embedded Al2O3 minerals, such as glass and clay, influenced graphitization, as they most likely acted as catalysts for crystal growth in the basal direction. However, the graphitized samples, as a whole, do not compare well against a reference natural graphite sample despite some particles in select char concentrates appearing to be graphitized following graphitization.


Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4208
Author(s):  
Qiang Han ◽  
Zhan Qu ◽  
Ping Wang ◽  
Gang Bi ◽  
Guanzheng Qu

The fracture toughness of shale is a basic parameter that can provide effective theoretical support for wellbore stability and hydraulic fracturing of a shale reservoir. Due to the composition and microstructure, there are many problems in evaluating the mechanical properties of shale in a macroscopic test. In this paper, the composition and pore distribution of shale were studied by X-ray diffraction and nuclear magnetic resonance. Scanning electron microscopy was used to characterize the pore structure. The setting of experimental parameters and the selection of the indenter were discussed. Micro-indentation technique was proposed and applied to fracture toughness analysis of shale. The results show that Berkovich indenter is more suitable for shale indentation test than Vickers indenter. Fracture toughness of shale indentation is obviously affected by surface roughness and indentation position. Fracture toughness of shale decreases slightly with the increase of the indentation load. The energy analysis result presents that the effect of cracking on the ratio of total/unloading work is minimal when there is no significant stripping on the shale surface. Compared with the experimental method, energy methods can obtain all the analysis parameters from a single indentation test. The results of comparative analysis with macroscopic experiments display that micro-indentation test can effectively predict the macroscopic fracture toughness of shale.


2020 ◽  
Vol 17 (5) ◽  
pp. 465-474
Author(s):  
Kwan Woo Choi ◽  
Soonwook Kwon ◽  
Sung-Bom Pyun ◽  
Woo-Suk Tae

Objective Although neuroimaging studies have shown volumetric reductions, such as the anterior cingulate, prefrontal cortices, and hippocampus in patients with major depressive disorder (MDD), few studies have investigated the volume of or shape alterations in the subcortical regions and the brainstem. We hypothesized that medication-naïve female adult patients with MDD might present with shape and volume alterations in the subcortical regions, including the brainstem, compared to healthy controls (HCs).Methods A total of 20 medication-naïve female patients with MDD and 21 age-matched female HCs, underwent 3D T1-weighted structural magnetic resonance scanning. We analyzed the volumes of each subcortical region and each brainstem region, including the midbrain, pons, and medulla oblongata. We also performed surface-based vertex analyses on the subcortical areas and brainstem.Results Female patients with MDD showed non-significant volumetric differences in the subcortical regions, whole brainstem, and each brainstem region compared to the HCs. However, in the surface-based vertex analyses, significant shape contractions were observed in both cerebellar peduncles located on the lateral wall of the posterior brainstem [threshold-free cluster enhancement, corrected for family-wise error (FWE) at p<0.05] in patients with MDD.Conclusion We revealed shape alterations in the posterior brainstem in female patients with MDD.


2019 ◽  
Vol 9 (6) ◽  
pp. 4567-4574 ◽  

The green synthetic processes have synthetized five Cr(III), Mn(II), Fe(III), Co(III) and Ni(II) complexes. In the current study, their synthesis by ball mining is decorated in a simple one-pot synthesis, cost efficiency, easy to measure for commercial manufacture, effective synthesis conditions such as moderate temperature and shorter length, thus preventing further by-products which could cause environmental harm, and being environmentally friendly as it is. All five complexes are well-defined, polyncrystalline materials as their Powder X-ray diffraction patterns indicate. The characterization of these complexes had been Fourier Transform Infrared Spectroscopy(FT-IR), 1H-13C Nuclear magnetic resonance, Scanning Electron Microscopy (SEM), electronic absorption spectral studies as well as magnetic studies and Powder XRD techniques.


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