The divided subtracted inversion recovery (dSIR) is a high T contrast technique that shows changes in white matter in patients with traumatic brain injury and hypoxic injury. The changes can be explained by small differences in T; however, to date, there has been no independent validation of the technique using a standard reference. The present study develops the theory of the dSIR signal and performs validation using the NIST/ISMRM T phantom.
View Article and Find Full Text PDFJ Magn Reson Imaging
August 2024
The cartilaginous endplate (CEP) plays a pivotal role in facilitating the supply of nutrients and, transport of metabolic waste, as well as providing mechanical support for the intervertebral disc (IVD). Recent technological advances have led to a surge in MR imaging studies focused on the CEP. This article describes the anatomy and functions of the CEP as well as MRI techniques for both qualitative and quantitative assessment of the CEP.
View Article and Find Full Text PDFUltra-high contrast (UHC) MRI describes forms of MRI in which little or no contrast is seen on conventional MRI images but very high contrast is seen with UHC techniques. One of these techniques uses the divided subtracted inversion recovery (dSIR) sequence, which, in modelling studies, can produce ten times the contrast of conventional inversion recovery (IR) sequences. When used in cases of mild traumatic brain injury (mTBI), the dSIR sequence frequently shows extensive abnormalities in white matter that appears normal when imaged with conventional T-fluid-attenuated IR (T-FLAIR) sequences.
View Article and Find Full Text PDFDivided and subtracted MRI is a novel imaging processing technique, where the difference of two images is divided by their sum. When the sequence parameters are chosen properly, this results in images with a high T or T weighting over a small range of tissues with specific T and T values. In the T domain, we describe the implementation of the divided Subtracted Inversion Recovery Sequence (dSIR), which is used to image very small changes in T from normal in white matter.
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