ARMRIT-Practice test (part 1: Mri Physics and Ins.)Questions and Answers with complete

The T1 process is also known as: - Answer-Spin Lattice Which type of electromagnetic coils produce smaller magnetic field which allow spatial localization to be performed? - Answer-Gradient coils The component Mxy is most associated with: - Answer-Transverse to Bo; T2 relaxation; Transverse magnetization The resonance frequency of any substance in a magnetic field can be calculated by employing the: - Answer-Larmor equation Once the patient's area of interest is placed in the main magnetic field of the MRI system, the hydrogen protons will: - Answer-Precess parallel to Bo The longitudinal component of the NMV is designated: - Answer-Mz Which type of MRI magnet requires no electricity to maintain it's magnetic field and can weigh from 18,000 lb. to 200,000 lb.? - Answer-Permanent The component Mz is the most associated with: - Answer-Parallel to Bo; T1 relaxation; Longitudinal magnetization Which statement is true of the relaxation process? - Answer-Without the effects of T2* (star), T2 decay continues To describe the uniformity of the Mri systems main magnetic field, the term employed is: - AnswerHomogeneity Methemoglobin and gadolinium based contrast agents have magnetic properties that shorten both T1 and T2 values in adjacent tissues. What type of substances are they? - Answer-ParamagneticT1 is the measurement of time for the longitudinal component of the net magnetization vector to recover what percentage of its original value after the application of a 90 degree radio-frequency pulse? - Answer-63% At any one time, human body tissue, in general, is made up of 50-90% of what substance? - AnswerH2O In a loop of conductor in which an electric current is introduced and maintained, a magnetic field will be produced in the center perpendicular to the flow of electric current this is called: - AnswerFaraday's Law On a very basic level , the three basic components required to attain MR signals are: - AnswerMagnetic field, Proton, Radio-wave