and Answers Latest Version Rated A+
What does ARRT stand for?
✔✔ American Registry of Radiologic Technologists
What is the main purpose of MRI shielding?
✔✔ To prevent external radiofrequency interference
Which part of the MRI system is responsible for creating the magnetic field?
✔✔ Main magnet
What is the purpose of the RF coil in MRI?
✔✔ To transmit and receive radiofrequency signals
Why is hydrogen used in MRI imaging?
✔✔ It has a single proton that aligns with the magnetic field
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,What happens when an RF pulse is applied in MRI?
✔✔ Hydrogen nuclei absorb energy and move to a higher energy state
What is T1 relaxation time?
✔✔ The time it takes for protons to realign with the magnetic field
What is T2 relaxation time?
✔✔ The time it takes for protons to lose phase coherence
What effect does increasing TR have on image contrast?
✔✔ Increases signal and reduces T1 contrast
What effect does increasing TE have on an MRI image?
✔✔ Increases T2 contrast and reduces signal
What is the purpose of a gradient coil in MRI?
✔✔ To localize signals from different areas of the body
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,Why must metallic implants be checked before an MRI scan?
✔✔ They may cause heating or movement in the magnetic field
What is the most common contrast agent used in MRI?
✔✔ Gadolinium
Why is fat suppression used in MRI?
✔✔ To reduce fat signal and improve tissue contrast
Which MRI technique measures blood flow in the brain?
✔✔ Functional MRI (fMRI)
What is the primary safety concern with gadolinium contrast?
✔✔ Risk of nephrogenic systemic fibrosis
Why is patient screening essential before an MRI exam?
✔✔ To check for contraindications like pacemakers or implants
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, What is the term for the loud knocking sounds heard during an MRI scan?
✔✔ Gradient coil switching
What is aliasing in MRI?
✔✔ A type of artifact caused by undersampling
How can motion artifacts be reduced in MRI?
✔✔ By instructing the patient to stay still and using motion correction techniques
What does FOV stand for in MRI?
✔✔ Field of view
What does SNR stand for in MRI?
✔✔ Signal-to-noise ratio
Which imaging sequence is best for visualizing edema?
✔✔ T2-weighted imaging
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