The phase information of magnetic resonance (MR) phase image can be used in many MR imaging techniques, but phase wrapping of the images often results in inaccurate phase information and phase unwrapping is essential for MR imaging techniques. In this paper we analyze the causes of errors in phase unwrapping with the commonly used Goldstein Brunch-cut algorithm and propose an improved algorithm. During the unwrapping process, masking, filtering, dipole- remover preprocessor, and the Prim algorithm of the minimum spanning tree were introduced to optimize the residues essential for the Goldstein Brunch-cut algorithm. Experimental results showed that the residues, branch-cuts and continuous unwrapped phase surface were efficiently reduced and the quality of MR phase images was obviously improved with the proposed method.
Algorithms ; Magnetic Resonance Imaging ; methods

The required time of conventional magnetic resonance spectroscopic imaging technique is too long to be applied to clinic. It is necessary to develop the fast methods for magnetic resonance spectroscopic imaging. Nowadays there are 7 kinds of methods presented, which come from MRI techniques. In this contribution the conventional spectroscopic imaging and 7 sorts of fast spectroscopic imaging are elaborated. It is envisaged that more rapid imaging techniques will be designed, if these arbitrary trajectory reconstruction methods in MRI are applied to spectroscopic imaging.
Magnetic Resonance Imaging ; methods ; trends ; Magnetic Resonance Spectroscopy ; methods

Magnetic Particle Imaging (MPI) is a new medical imaging tool, which was born at the beginning of the 21st century. Compared with traditional imaging techniques, the preliminary research indicates that MPI shows higher sensitivity, resolution and imaging speed. This article presents the principle of MPI, its recent development from three different perspectives is introduced.
Diagnostic Imaging ; Magnetic Phenomena ; Magnetic Resonance Imaging ; methods ; Molecular Imaging

The paper introduces a method of self-gated signal's collection based on TrueFisp sequence, during self-gated cardiac magnetic resonance imaging. There is no significant difference in its image quality and only a slight loss in efficiency in comparison with MRI images by ECG-based triggering.
Electrocardiography ; methods ; Magnetic Resonance Imaging ; methods

The accurate diagnosis and staging of hepatic fibrosis is crucial for treatment and prognosis of liver disease. The current gold standard is liver biopsy, but it cannot be used in population-based screening, and has well known drawbacks if used for monitoring of disease progression or treatment results. Functional MR, as a non-invasive method, is increasingly used in hepatic fibrosis and became the current hot spot. Most recently available functional MR imaging techniques including diffusion weighted imaging, perfusion weighted imaging and MR spectroscopy can detect cirrhosis or fibrosis reasonably accurately. However, to date only MR elastography has been able to stage fibrosis or diagnose mild disease. MR diffusion weighted appears next most promising.
Diffusion Magnetic Resonance Imaging ; Humans ; Liver Cirrhosis ; classification ; diagnosis ; Magnetic Resonance Imaging ; methods ; Magnetic Resonance Spectroscopy

In this article, an introduction is given on the structure of RF subsystem, its main parameters and impact on the performance of MRI and RF techniques and its development. Furthermore, pivotal parameters provided by different suppliers are quoted and compared in functionality aspect.
Magnetic Resonance Imaging ; instrumentation ; methods ; Radio Waves

This paper is to introduce the method in which the SIEMENS' MR images are converted into BMP format ones based on the correct format analysis of SIMENS' MR images, we condude that the conversion from SIEMENS' MR image to BMP image can be realized by software design.
Computers ; Humans ; Magnetic Resonance Imaging ; methods ; Software

Calculation methods of coil sensitivity in parallel MRI were elaborated, compared and analyzed.
Algorithms ; Magnetic Resonance Imaging ; instrumentation ; methods

To optimize the configuration of the conventional SE and FSE sequence parameters in low field MRI. With the combination of larger vision, relatively thinner slice thickness, small number of excitation (NEX = 1 or 2), the signal-to-noise ration and the spatial resolution on follow-up images are moderate, the scan time is significantly shorter along with fewer motion artifacts, the check success rate is improved.
Equipment Design ; Magnetic Resonance Imaging ; instrumentation ; methods

Grounding technique is very important to ensure the human safety, imaging devices' safety and the devices' reliable running. This paper expatriates the principles of the grounding safety, interference rejection earth, and the grounding modes and the mode selection for each imaging devices and equipments, and related grounding requirements.
Equipment Safety ; methods ; Magnetic Resonance Imaging ; instrumentation