Mri Registry Test Bank With Actual Written Questions And Answers

MRI Registry Review solved solution To maximize SNR, which parameter can be adjusted a) decrease NSA (NEX) b) increase matrix (FOV) c) decrease slice thickness d) increase NSA (NEX) - d) increase NSA (NEX) A consequence of maximizing resolution using an increase image matrix (FOV) is: a) increase SNR b) decrease scan time c) increase scan time d) chemical shift - c) increase scan time The parameters you can adjust to minimize scan time is: - decrease TR According to Faraday's law, the component of the magnetization in the _______________ plane induces a current in RF receiver coils. a) longitudinal b) scan c) transverse d) orthogonal - c) transverse What is the unique advantage of phased array coils? a) They are several receive coils linked to one receive channel. b) They are one large receive coil with several receive channels. c) They are several receive coils each with a different receive channel. d) They provide higher SNR because of their combined re ceive channel design. - c) They are several receive coils each with a different receive channel. What is the gradient rise time? a) the time it takes to turn on the gradient once the scan has been initiated b) the time it takes to ramp the gradient to full strength c) a measure of the gradient's maximum field strength capacity d) shorter for the echo planar imaging vs. routine imaging - b) the time it takes to ramp the gradient to full strength If a proton m oves across a gradient of increasing strength, what would happen to its precession? a) it would dephase b) it would not be affected c) it would accelerate d) it would stop - c) it would accelerate Which gradient is used to alter the magnetic field strengt h and thus precessional frequency to select sagittal slices? a) z-gradient b) x-gradient c) y-gradient d) none of the above - c) y-gradient Increasing the amplitude of the slice -select gradient causes the following result if the transmit bandwidth remains constant: a) greater signal return b) an increase in slice thickness c) a different slice orientation d) a decrease in slice thickness - d) a decrease in slice thickness What is the unit of measurement for the strength of the gradient magnetic field? a) W/kg b) mHz/cm c) mT/m d) mHz/G - c) mT/m A factor that governs the efficiency of the passage of current is the inherent resistance of the coil. Which law is used to determine the degree of resistance along a wire? a) Faraday's law b) Tesla's law c) Ohm's law d) Helmholtz's law - c) Ohm's law Which of these is the magnetic field strength proportional to? a) the amount of current passed through the loops of the wire b) the number and size of the loops c) how closely the loops are spaced d) all of the above - d) all of the above What procedures are carried out during "prescan"? a) tuning coils, setting center frequency b) tuning coils, setting center frequency, adjusting transmit attenuation c) tuning coils, setting center frequency, adjusting tran smit and receive attenuation d) tuning coils, adjusting transmit and receive attenuation - c) tuning coils, setting center frequency, adjusting transmit and receive attenuation Which of the following items can safely enter MRI safety zone 4 without resear ch? a) MR safe wheelchair b) Unlabeled oxygen tank c) MR conditional pacemaker d) MR unsafe stretcher - a) MR safe wheelchair A quench and release of cryogens may cause which of the following to occur in the scan room? a) electronic malfunction b) reduct ion of oxygen c) increase in temperature d) an explosion - b) reduction of oxygen MR conditional means an object is what? a) demonstrated to pose no known hazards in a specified MRI environment with no specified conditions of use b) demonstrated to pose known hazards in a specified MRI environment with specified conditions of use c) demonstrated to pose no known hazards in a specified MRI environment with specified conditions of use d) safe to enter the scan room with no research o r trepidation in regards to its safety - c) demonstrated to pose no known hazards in a specified MRI environment with specified conditions of use Which of the following is correct regarding the use of surface coils? a) frayed cables are okay to use if the coil is still functional b) unplug surface coils from the bore of the magnet before scanning c) cross or loop cables if there are two or more present in the bore d) ensure they do not touch the patient or the sides of the bore - d) ensure they do not touc h the patient or the sides of the bore True or false? The technologist does not need to remove an inpatient's ECG leads prior to scanning as long as they are not scanning the patient's chest or abdomen area? - False! Non MR safe ECG leads can cause burns on patients undergoing MRI regardless of the area being scanned. What does DICOM stand for: A) Digital Imaging and Communications in Medicine B) Disney Imaging and Communications in Mickey C) Digital Intense and Completing in Medicine D) Digital Imaging w ith Computes in Medicine - A) Digital Imaging and Communications in Medicine How many bytes are needed to store one alphanumeric character? A) 32 B) 1 C) 29