The Estimate of the Impact of Coccyx Resection in Surgical Field Exposure During Abdominal Perineal Resection Using Preoperative High-Resolution Magnetic Resonance

2018 ◽  
Vol 42 (11) ◽  
pp. 3765-3770
Author(s):  
Guilherme Pagin São Julião ◽  
Cinthia D. Ortega ◽  
Bruna Borba Vailati ◽  
Francisco A. B. Coutinho ◽  
Gustavo Rossi ◽  
...  
2021 ◽  
Vol 13 (9) ◽  
pp. 1699-1707
Author(s):  
Boya Li ◽  
Aihua Xiong ◽  
Xiaotong Yang ◽  
Qiong Yang ◽  
Jing Liu

Magnetic nanoparticles were used in medical images, which could further improve image clarity, while watersoluble nanoparticles put forward more new requirements for the biocompatibility of nanoparticles. This research adopted a simple and novel method to prepare water-soluble iron oxide nanoparticles. First, transmission electron microscope (TEM) was used to analyze the size distribution of the prepared product; X-ray diffraction (XRD) was used to test the crystal structure of the prepared sample; the fast Fourier transform (FFT) spectrum was introduced to analyze the structural properties of the nanoparticles; the nanoparticle aqueous solutions of different concentrations were designed, and the impact of water-soluble nanoparticles on magnetic resonance imaging (MRI) was examined with the nuclear magnetic resonance spectrometer. At the same time, the prepared water-soluble nanoparticle solution was used for high-resolution tumor wall imaging of patients with unruptured intracranial aneurysm (IA) to compare the imaging effect of the aneurysm wall before and after the introduction of nanoparticles. In the material characterization test of nanoparticles, the prepared samples did not have certain iron oxide characteristic peaks, which means the synthesized iron oxide nanoparticles did not have a fixed crystal morphology. The samples tested by energy dispersive spectrometer (EDS) also contained Fe, O, C and Na. The average particle size was 5.8 nm. It was found under high-resolution TEM that the particle mirror spacing was 0.48 nm, which was consistent with the 111-crystal plane of Fe3O4; The magnetic hysteresis loop test confirmed that when the concentration of nanoparticles increased, the solution would form a magnetic fluid. When the concentration of aqueous solution of nanoparticles increased, the corresponding MRI signal would be significantly enhanced. It was used in the MR scan of patients with unruptured IA. Nanoparticle solution could increase the visibility of the aneurysm, and the image quality of the aneurysm wall could be significantly enhanced.


Author(s):  
Alan P. Koretsky ◽  
Afonso Costa e Silva ◽  
Yi-Jen Lin

Magnetic resonance imaging (MRI) has become established as an important imaging modality for the clinical management of disease. This is primarily due to the great tissue contrast inherent in magnetic resonance images of normal and diseased organs. Due to the wide availability of high field magnets and the ability to generate large and rapidly switched magnetic field gradients there is growing interest in applying high resolution MRI to obtain microscopic information. This symposium on MRI microscopy highlights new developments that are leading to increased resolution. The application of high resolution MRI to significant problems in developmental biology and cancer biology will illustrate the potential of these techniques.In combination with a growing interest in obtaining high resolution MRI there is also a growing interest in obtaining functional information from MRI. The great success of MRI in clinical applications is due to the inherent contrast obtained from different tissues leading to anatomical information.


Author(s):  
N. D. Browning ◽  
M. M. McGibbon ◽  
M. F. Chisholm ◽  
S. J. Pennycook

The recent development of the Z-contrast imaging technique for the VG HB501 UX dedicated STEM, has added a high-resolution imaging facility to a microscope used mainly for microanalysis. This imaging technique not only provides a high-resolution reference image, but as it can be performed simultaneously with electron energy loss spectroscopy (EELS), can be used to position the electron probe at the atomic scale. The spatial resolution of both the image and the energy loss spectrum can be identical, and in principle limited only by the 2.2 Å probe size of the microscope. There now exists, therefore, the possibility to perform chemical analysis of materials on the scale of single atomic columns or planes.In order to achieve atomic resolution energy loss spectroscopy, the range over which a fast electron can cause a particular excitation event, must be less than the interatomic spacing. This range is described classically by the impact parameter, b, which ranges from ~10 Å for the low loss region of the spectrum to <1Å for the core losses.


Author(s):  
G.A. Kechek ◽  
◽  
I.V. Rubtsova ◽  
N.A. Totolyan ◽  
A.A. Totolyan ◽  
...  

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