ARMRIT- Clinical Application Questions and Answers(A+ Solution guide)

A technique to avoid "cross-talk"? - Answer-Interleaving Combining a metal ion with ligand reduces tendency to bind to proteins, enzymes or membranes. The degree to which they dissociate is a measure of their? - Answer-Toxicity The "best" technique for improving image quality is to increase? - Answer-NEX Tissues that have low (short) relaxation times have? - Answer-High (long) relaxation rates Linear relationship between frequency and position is superimposed on Bo by the Gp. The hydrogen protons relative precessional frequencies determine? - Answer-Phase shifts What is the pixel formula? - Answer-FOV/Matrix An analogy for decoding the MR signal through Fourier Transform? - Answer-Basilar membrane processing sound Decreasing Matrix will? - Answer-Decrease pixel size Spatial resolution is an image quality factor determined by? - Answer-Slice thickness and pixel size Inversion time, in Inversion Recovery pule sequence is the interval between? - Answer-180 and 90 degree pulses Decreasing TE will? - Answer-Increase # of slices The least expensive parameter in time, of the following that affect time, to increase for improving image quality is? - Answer-TR FLAIR stands for? - Answer-Fluid Attenuated Inversion RecoveryIn a horizontal field magnet, what is primary Gs for Axial slice? - Answer-Gz A pulse sequence that replaces the second RF pulse with gradient magnet field to rephase the transverse vector and produce an echo is called? - Answer-Gradient Echo In spatial localization, which gradient is considered to be "logical"/"read-out"? - Answer-Gx Increasing Matrix will? - Answer-Increase in resolution In IR pulse sequence, what will produce a STIR fat supression? - Answer-80-120 range Decreasing NEX will? - Answer-Decrease SNR and Resolution A generation of frequency differences along a particular direction of a slice is called? - AnswerFrequency encoding When increasing the parameter, matrix, the pixel size will? - Answer-Decrease Increasing NEX will? - Answer-Increase SNR and Resolution Information acquired when you increase/decrease frequency of the RF pulse of Gs, causing the center of tyhe excited plane to change with the center of Gs RF pulse is? - Answer-Slice position Gadolinium..? - Answer-Produces randomly fluctuating magnetic fields in its immediate environment Increasing TE will? - Answer-Decrease SNR and # of slices What pulse image technique is employed in all implemented of MRA? - Answer-GE In a horizontal field magnet, what is the primary Gs for Sagittal slice? - Answer-Gx