Written in English
A major limitation to achieving fast imaging with breast MRI is the necessity of a fat suppression process, since the lipid signal appears bright in MRI and may otherwise be misidentified as a lesion. The goal of this document is to thoroughly discuss current methods of fat suppression, and to investigate a means to reduce scan time while still achieving effective reduction in fat signal. A method is proposed by which a specific fat suppression technique, fat saturation, is applied less frequently to save time. Within the capacity of this method, the variable parameters are investigated and optimized in an attempt to produce images with the least fat contamination in the shortest period of time. This technique is demonstrated in phantoms and in-vivo, and compared with other fat suppression techniques upon which it has advanced.
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If fat saturation is difficult, the patient must be instructed to remain very still during the examination so that the subtraction images will be interpretable. Inhomogeneous fat saturation is a common problem and may be difficult to correct (, Fig 12a,). Inhomogeneous fat saturation can be due to field inhomogeneity, which may be improved by Cited by: Fat suppression is commonly used in magnetic resonance (MR) imaging to suppress the signal from adipose tissue or detect adipose tissue It can be applied to both T1 and T2 weighted sequences. Due to short relaxation times, fat has a high signal on magnetic resonance images (MRI). It is also possible to save time by applying the Fat-Sat pulses at intervals less frequently than before every TR interval (e.g. Siemens' "Quick FatSat"). However, the time between Fat-Sat pulses cannot be extended longer than about msec, because significant longitudinal recovery of fat will occur in that interval due to its short T1. Optimal K-Space Acquisition Reordering for Intermittent Fat Saturation in Breast MRI K. L. Desmond1, E. Ramsay2, D. B. Plewes1,2 1Medical Biophysics, University of Toronto, Toronto, Ontario, Canada, 2Imaging Research, Sunnybrook and Women’s Colle ge Health Sciences Centre, Toronto, Ontario, Canada Introduction Breast imaging is typically aided by fat .
MRI image appearance. The easiest way to identify T1 weighted fat saturated images is to look for adipose tissues in the body (e.g. subcutaneous fat and fat in bone marrow). Areas contain adipose tissues appear dark on T1 weighted fat saturated images. All the other characteristics of the T1 weighted fat saturated images remain the same as the. Thesis title: K-Space ranking for improved fat saturation in Breast MRI. McMaster University. McMaster University Bachelor of Science () Mathematics and Physics (double major) Comparison of Biphasic and Reordered Fat Suppression for Dynamic Breast MRI Journal of Magnetic Resonance Imaging Jun Other authors. See : Project Scientist at CAMH. : AAPM 2 Breast MRI Artifacts Common artifacts in breast MRI • Motion • Truncation artifacts • Out of volume wrapOut of volume wrap • SusceptibilitySusceptibility artifacts artifacts • Signal nonSignal non--uniformityuniformity • Poor or nonPoor or non- -uniform fat saturationuniform fat saturation Motion artifacts Occur in the phase encoding direction. Example of Diagnostic Breast MRI Protocol 3D T1W bilateral multi-phase series, Gd contrast, fat sat 3-plane localizer Axial Bilateral T1W series 2D Sag Unilateral T2W fat sat bright fluid series Axial Post-Gd high resolution (x), fat sat, T1W series May include spectroscopy, diffusion-weighted imaging (DWI).
subcutaneous fat improved the contrast of the en-hanced mass to subcutaneous fat and that of breast parenchyma to subcutaneous fat. The enhanced le-sions were also heightened against the breast paren-chyma (Fig. 2). A remaining partially unsuppressed re-gion of subcutaneous fat was sometimes noted (Figs. 1 and 2). 1. Introduction. Contrast-enhanced MRI has significantly increased sensitivity to breast cancer, to 81–98%,,,, but specificity has been lagging, with reports varying between 30% and 85%,.Thus, alternative approaches to producing clinically useful contrast in magnetic resonance (MR) images are needed. Breast magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer 1,2 and is increasingly being used for surgical planning 3 and treatment monitoring. 4,5 The current state of breast MRI focuses on collecting morphologic and dynamic information at a T magnetic field strength. High-resolution images yield information regarding tumor . Breast MRI has become an essential examination for investigating the pathological breast. Over the past 10 years or so, a number of papers have described good practice in performing this examination,.Breast MRI is the imaging of tumour angiogenesis, based on studying dynamic uptake of contrast agent in T1 imaging, which varies with the microvascularisation characteristics of breast .