ARRT MRI Exam Prep (Latest 2024/ 2025 Update) Questions and Verified Answers| Grade A| 100% Correct

ARRT MRI Exam Prep (Latest 2024/ 2025 Update) Questions and Verified Answers| Grade A| 100% Correct Q: From a resting state in which the fully relaxed net magnetization is aligned along the longitudinal direction, what would the application of a single 45 RF pulse result in? a. equal amounts of transverse magnetization and longitudinal magnetization b. greater longitudinal magnetization than transverse magnetization c. greater transverse magnetization than longitudinal magnetization d. zero longitudinal magnetization Answer:: a. Q: Which of the following if the definition of T2 relaxation? a. the time at which the transverse magnetization has decayed to 63% of its full value b. the time at which the transverse magnetization has decayed to 37% of its full value Answer:: b. Q: By increasing the TE from 80ms to 120ms on a spin-echo pulse sequence, which of the following is the expected result? a. better tissue contrast based on the tissues' T1 characteristics b. a stronger signal in the MR echo c. fewer protons would experience spin-spin interactions d. better tissue contrast based on the tissues' T2 characteristics Answer:: d. Q: If six successive 180 RF pulses are applied, following a 90 RF pulse, how many echoes will be formed? a. one b. two c. six d. eight Answer:: c. Q: If the six successive 180 RF pulses are applied, following a 90 RF pulse, echo ____ will contain the greatest signal? a. one b. three c. five d. six Answer:: a. Q: Using a spin-echo pulse sequence which generates two echoes, imagine a hypothetical tissue in which protons never experience spin-spin interactions. How does the signal from the first echo compare to the signal from the second echo? a. its frequency is higher b. its frequency is lower c. its the same size d. it is smaller in size Answer:: c. Q: What is the time from the 180 RF pulse to the echo? a. TE b. TR c. 2.0 x TE d. 0.5 x TE Answer:: d. TE/2 TAU Q: Which of the following dephasing mechanisms is NOT rephased by a 180 RF pulse? a. magnetic susceptibility b. phase effects of a chemical shift c. spin-spin interactions d. magnetic field inhomogeneities Answer:: c. Q: Which of the following parameters controls the amount of contrast seen in an image due to T2 relaxation? a. TI b. TR c. TM d. TE Answer:: d. Q: The effect of an IV. administered paramagnetic contrast agent used in MRI is a shortening of a T1 relaxation time of the protons within any perfused tissue. A vascular lesion would appear ____ on a T1-W contrast-enhanced image as compared to its appearance on a T1-W unenhanced image. a. the same b. darker c. as a signal void d. brighter Answer:: d. Q: In a given MR system, the magnetization of protons within the patient precesses at 63.83MHz. Without the interference of any other system component, what is the expected result if the RF energy is applied at a frequency of 63.83 MHz? a. only the patient's protons in a sagittal slice will be disturbed by the external energy b. all of the patient's protons within range of the transmitting antenna will be disturbed by the external energy c. none of the patient's protons would be disturbed by the external energy d. only the patient's protons in a transverse slice will be disturbed by the external energy Answer:: b. Q: If the field strength experienced by a patient within an MR magnet is increased, the precessional frequency of the magnetization of the patient's protons will: a. increase b. reverse its spin direction c. remain unaffected d. decrease Answer:: a. Q: The energy used to form MR images is ____ the patient's tissues. a. attenuated by b. magnified by c. reflected off of d. released from