MRI Artifacts Questions and Answers Latest Update Graded A+

MRI Artifacts Questions and Answers Latest Update Graded A+ What is the main cause of motion artifacts in MRI scans? Patient movement during the scan Why do metal implants create artifacts in MRI images? They distort the magnetic field and disrupt signal uniformity What type of artifact appears as repeating ghost images across the scan? Nyquist or phase ghosting artifact Why does aliasing occur in MRI? When the field of view is too small, signals from outside the imaging area wrap around What can be done to reduce motion artifacts in MRI scans? Use motion correction techniques, shorter scan times, or patient immobilization 2 Why do susceptibility artifacts occur in MRI? Due to differences in magnetic properties between tissues and foreign materials What causes chemical shift artifacts in MRI images? The difference in resonance frequency between fat and water How can radiofrequency artifacts appear in an MRI scan? External RF interference affecting signal reception Why do truncation artifacts appear in MRI? Due to limited data sampling, causing edge ringing in high-contrast areas What is the best way to reduce metal artifacts in MRI? Use metal artifact reduction techniques, higher bandwidth, or alternative sequences Why does incomplete fat suppression occur in MRI scans? Improper sequence selection or magnetic field inhomogeneity 3 What artifact is caused by blood flow or cerebrospinal fluid motion in MRI? Flow-related artifacts Why does Gibbs ringing occur in MRI images? Due to under-sampling in k-space, leading to oscillations near sharp edges What adjustment can help reduce susceptibility artifacts? Using shorter echo times (TE) and high-bandwidth sequences Why do zipper artifacts appear in MRI scans? Caused by RF interference entering the scanner room What can be done to minimize aliasing artifacts? Increasing the field of view or using anti-aliasing techniques Why do pulsation artifacts commonly occur in brain and spinal MRI scans? Due to blood vessel movement affecting phase encoding 4 What causes dielectric artifacts in MRI? High-field MRI systems interacting with large patients, causing uneven signal distribution How can cross-talk artifacts be reduced in MRI?