Optimizing Flip Angle Selection in Breast MRI for Accurate Extraction and Visualization of T1 Tissue Relaxation Time
نویسنده
چکیده
Contrast enhanced MRI is a popular diagnostic technique for characterizing angiogenesis and detecting breast cancer. Though conventionally measured relative signal enhancement (RSE) is not linearly proportional to contrast agent concentration, relative enhancement of T1 tissue relaxation time is. Therefore, measurement of T1 using low flip angle acquisitions is essential for characterizing tumors. In this paper, we present a framework to select optimum flip angles analytically from minimizing the error in T1. The method is flexible and adaptive to noise as reflected in a critical comparison with the most recent method for optimum flip angle selection. Evaluation of our method on clinical Breast MR data of 2 women shows consistent superiority in mapping accurately T1 in pre contrast enhanced images. Key-Words : Magnetic Resonance Imaging, Breast Imaging, T1 estimation.
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Transmit B1+ field inhomogeneity and T1 estimation errors in breast DCE-MRI at 3 tesla.
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