CH 26 – MRI questions with correct answers 2023

CH 26 – MRI questions with correct answers 2023TRUE or FALSE MRI is a noninvasive procedure. - correct answer TRUE TRUE or FALSE MRI uses ionizing radiation. - correct answer FALSE Which of the following the main element effected by MRI? a. oxygen b. nitrogen c. hydrogen d. carbon - correct answer c. hydrogen Atoms with ___________ are considered magnetic and therefore are effected by MRI. a. high atomic numbers b. low atomic numbers c. even atomic numbers d. odd atomic numbers - correct answer d. odd atomic numbers Atoms with odd atomic numbers are often what is imaged by MRI because they: a. are more dense b. are less dense c. have strong magnetic properties d. respond better to contrast - correct answer c. have strong magnetic properties When a magnetic field is applied, protons: a. line up parallel to the magnetic field b. line up perpendicular to the magnetic field c. point toward the magnetic field d. are unaffected by the magnetic field - correct answer a. line up parallel to the magnetic field When placed in a magnetic field, hydrogen protons wobble like a spinning top. This defines: a. precession b. radio frequency (RF) c. resonance d. pulse sequence - correct answer a. precession Each atom has its own: a. precession b. frequency c. resonance d. pulse sequence - correct answer b. frequency The absorption of energy by precessing protons is termed: a. precession b. radio frequency (RF) c. resonance d. pulse sequence - correct answer c. resonance For hydrogen protons in a magnetic field to absorb energy from radio waves: a. the protons must have an even atomic number b. the protons must be perpendicular to the magnetic field c. the frequency of the proton has to match the RF of the scanner d. the protons must contain contrast media - correct answer c. the frequency of the proton has to match the RF of the scanner Resonant frequency depends on: a. the atomic number of the proton b. the presence of contrast c. the shape of the proton d. the strength of the magnetic field - correct answer d. the strength of the magnetic field When the radiofrequency is turned ON, the protons align ___________ to the magnetic field; when the radiofrequency is turned OFF, the protons align __________ to the magnetic field. a. perpendicular b. parallel - correct answer b. parallel; a. perpendicular The rates of signal decay and the return of protons to their equilibrium is termed: