Multispectral Tissue Characterization In Magnetic Resonance Imaging Using Bayesian Estimation And Markov Random Fields

Author(s):  
M. Goldbach ◽  
W. Menhardt ◽  
J. Stevens
Sensors ◽  
2009 ◽  
Vol 10 (1) ◽  
pp. 266-279 ◽  
Author(s):  
Fabio Baselice ◽  
Giampaolo Ferraioli ◽  
Aymen Shabou

Author(s):  
I. Shirazu ◽  
Y. B Mensah ◽  
T. A Sackey ◽  
M. Boadu ◽  
E K Eduful ◽  
...  

Physical imaging technique described as Diffusion Weighted-Magnetic Resonance Imaging (DW-MRI) is based on classically principle of Brownian motion, where the molecules are thermal agitated and is highly influenced by the cellular availability of water. The aim of this study is to discuss the use of DW-MRI as a cancer diagnostic application tool using the basic physics principles as versus other available procedures and modalities in terms of accuracy and acceptability. Based on extravascular diffusion measurements where the measured signal is related to tissue cellularity, tissue organization and extracellular space tortuosity and on the intactness of cellular membranes that are intrinsically hydrophobic. The methodology involve the application of DW-MRI procedure, to qualitatively and quantitatively access DW-MR images to diagnose brain tumors, prostate and other organ cancers compared to other imaging modalities including other MRI procedures. It also include safety assessment and other consideration before, during and after imaging with MRI as compare to other radiological modalities. The results of the data of ten (10) MRI centers and 112 DW-MRI images and 99 other procedure and modalities were analysed, 34% were prostate cases, 27% were brain cases and 39% formed all other cases. In addition, DW-MRI compare to other single imaging procedure formed 53% of all diagnostic procedure that had 87% accurate predictability of prostate and brain cases. It can therefore concluded that DW-MRI is the best single imaging procedure that can be used to diagnose prostate cancers and brain tumors. It has a major advantage of non-ionizing radiation technique, with multiple planes image acquisitions, together with superior soft tissue contrast. In addition its perfusion allow for precise tissue characterization rather than merely 'macroscopic' imaging and superior visualization of both active parts of the brain during certain activities and understanding of the underlying networks. However, there are two outstanding challenges of DW-MRI scans in Ghana: it is expensive as compared to other modalities and not safe for patients with some metal implants. Despite these challenges, its advantages override its disadvantages and therefore it is recommended to clinicians as the first diagnostic tool to use in prostate cancer and brain tumor diagnoses.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Joāo dos Santos Periquito ◽  
Katharina Paul ◽  
Till Huelnhagen ◽  
Min-Chi Ku ◽  
Yiyi Ji ◽  
...  

AbstractDiffusion-weighted magnetic resonance imaging (DWI) is a non-invasive imaging technique sensitive to tissue water movement. By enabling a discrimination between tissue properties without the need of contrast agent administration, DWI is invaluable for probing tissue microstructure in kidney diseases. DWI studies commonly make use of single-shot Echo-Planar Imaging (ss-EPI) techniques that are prone to suffering from geometric distortion. The goal of the present study was to develop a robust DWI technique tailored for preclinical magnetic resonance imaging (MRI) studies that is free of distortion and sensitive to detect microstructural changes. Since fast spin-echo imaging techniques are less susceptible to B0 inhomogeneity related image distortions, we introduced a diffusion sensitization to a split-echo Rapid Acquisition with Relaxation Enhancement (RARE) technique for high field preclinical DWI at 9.4 T. Validation studies in standard liquids provided diffusion coefficients consistent with reported values from the literature. Split-echo RARE outperformed conventional ss-EPI, with ss-EPI showing a 3.5-times larger border displacement (2.60 vs. 0.75) and a 60% higher intra-subject variability (cortex = 74%, outer medulla = 62% and inner medulla = 44%). The anatomical integrity provided by the split-echo RARE DWI technique is an essential component of parametric imaging on the way towards robust renal tissue characterization, especially during kidney disease.


1987 ◽  
Vol 28 (3) ◽  
pp. 353-361 ◽  
Author(s):  
C. Thomsen ◽  
O. Henriksen ◽  
P. Ring

A new pulse sequence for in vivo diffusion measurements by magnetic resonance imaging (MRI) is introduced. The pulse sequence was tested on phantoms to evaluate the accuracy, reproducibility and inplane variations. The sensitivity of the sequence was tested by measuring the self diffusion coefficient of water with different temperatures. This phantom study showed that the water self diffusion could be measured accurately and that the inplane deviation was less than ±10 per cent. Seven healthy volunteers were studied with a 10 mm thick slice through the lateral ventricles, clear differences between grey and white matter as well as regional differences within the white matter were seen. In two patients with infarction, alternations in water self diffusion were seen in the region of the infarct. Likewise, pronounced changes in brain water self diffusion were observed in a patient with benign intracranial hypertension. The results indicate that brain water self diffusion can be measured in vivo with reasonable accuracy. The clinical examples suggest that diffusion measurements may be clinically useful adding further information about in vivo MR tissue characterization.


2011 ◽  
Vol 31 (3) ◽  
pp. 305-312 ◽  
Author(s):  
Kiyofumi Yamada ◽  
Masanori Kawasaki ◽  
Shinichi Yoshimura ◽  
Yukiko Enomoto ◽  
Takahiko Asano ◽  
...  

2014 ◽  
Vol 29 (6) ◽  
pp. 318-330 ◽  
Author(s):  
Vishal Sharma ◽  
Sukumaran Binukrishnan ◽  
U. Joseph Schoepf ◽  
Balazs Ruzsics

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