MRI in Practice Chapter 1 Questions and
Answers Latest Update 100% Pass
What is the primary property of hydrogen that makes it useful in MRI?
✔✔ It has a single proton that produces a strong magnetic moment
Why does the human body produce a signal in an MRI scanner?
✔✔ Hydrogen nuclei align with the magnetic field and emit signals when they relax
What happens when an external magnetic field is applied to hydrogen nuclei?
✔✔ They align either parallel or anti-parallel to the field
Why do some hydrogen nuclei align parallel to the magnetic field in MRI?
✔✔ Lower energy states are more stable, leading to more parallel alignment
What is precession in the context of MRI physics?
✔✔ The wobbling motion of hydrogen nuclei around the magnetic field
1
,How is the Larmor frequency determined in MRI?
✔✔ It is calculated using the gyromagnetic ratio and magnetic field strength
Why is the gyromagnetic ratio important in MRI?
✔✔ It defines the relationship between magnetic field strength and resonance frequency
What effect does increasing the magnetic field strength have on precession?
✔✔ It increases the precession frequency of hydrogen nuclei
What is meant by resonance in MRI physics?
✔✔ The absorption of radiofrequency energy by hydrogen nuclei at the Larmor frequency
What happens when hydrogen nuclei absorb RF energy during an MRI scan?
✔✔ They move to a higher energy state and become excited
Why do hydrogen nuclei return to their original state after RF excitation?
✔✔ They release absorbed energy and realign with the magnetic field
2
, What is T1 relaxation in MRI?
✔✔ The process of hydrogen nuclei realigning with the main magnetic field
Why is T2 relaxation important in MRI imaging?
✔✔ It measures the loss of phase coherence among hydrogen nuclei
What causes T2* decay in MRI?
✔✔ Magnetic field inhomogeneities and interactions between hydrogen nuclei
How does increasing the magnetic field strength affect T1 relaxation time?
✔✔ It generally increases T1 relaxation time
What is the difference between T1 and T2 relaxation?
✔✔ T1 is the recovery of longitudinal magnetization, while T2 is the decay of transverse
magnetization
Why does fat have a shorter T1 relaxation time than water?
✔✔ Fat molecules allow for faster energy transfer and quicker realignment
3
Answers Latest Update 100% Pass
What is the primary property of hydrogen that makes it useful in MRI?
✔✔ It has a single proton that produces a strong magnetic moment
Why does the human body produce a signal in an MRI scanner?
✔✔ Hydrogen nuclei align with the magnetic field and emit signals when they relax
What happens when an external magnetic field is applied to hydrogen nuclei?
✔✔ They align either parallel or anti-parallel to the field
Why do some hydrogen nuclei align parallel to the magnetic field in MRI?
✔✔ Lower energy states are more stable, leading to more parallel alignment
What is precession in the context of MRI physics?
✔✔ The wobbling motion of hydrogen nuclei around the magnetic field
1
,How is the Larmor frequency determined in MRI?
✔✔ It is calculated using the gyromagnetic ratio and magnetic field strength
Why is the gyromagnetic ratio important in MRI?
✔✔ It defines the relationship between magnetic field strength and resonance frequency
What effect does increasing the magnetic field strength have on precession?
✔✔ It increases the precession frequency of hydrogen nuclei
What is meant by resonance in MRI physics?
✔✔ The absorption of radiofrequency energy by hydrogen nuclei at the Larmor frequency
What happens when hydrogen nuclei absorb RF energy during an MRI scan?
✔✔ They move to a higher energy state and become excited
Why do hydrogen nuclei return to their original state after RF excitation?
✔✔ They release absorbed energy and realign with the magnetic field
2
, What is T1 relaxation in MRI?
✔✔ The process of hydrogen nuclei realigning with the main magnetic field
Why is T2 relaxation important in MRI imaging?
✔✔ It measures the loss of phase coherence among hydrogen nuclei
What causes T2* decay in MRI?
✔✔ Magnetic field inhomogeneities and interactions between hydrogen nuclei
How does increasing the magnetic field strength affect T1 relaxation time?
✔✔ It generally increases T1 relaxation time
What is the difference between T1 and T2 relaxation?
✔✔ T1 is the recovery of longitudinal magnetization, while T2 is the decay of transverse
magnetization
Why does fat have a shorter T1 relaxation time than water?
✔✔ Fat molecules allow for faster energy transfer and quicker realignment
3
