SWI QSM lecture (tugan) Questions With Complete Solutions

First things first, know what SWI and QSM stand for.. correct answer: SWI: suceptability weighted imaging QSM: Quantitative suceptability mapping What 2 things is SWI good at detecting? correct answer: Iron Deposition and Calcification What two very general catagories can you break the magnetic suceptability of a tissue into? correct answer: Paramagnetic components and diamagnetic components What sort of molecules contribute to the paramagnetic component? correct answer: The paramagnetic part comes from contributions of unpaired electrons in biomaterial molecules. Know the equation describing paramagnetic magnetization and what the individual variables are. correct answer: ns: spin density, μ: magnetic moment, kB: Boltzmann const. T: temperature. What produces the diamagnetic component? correct answer: The diagmagnetic component comes from the response of the orbiting electrons, even though their spins are paired evenly up and down producing no net spin. Know the equation describing the magnetization and what the variables represent correct answer: ne: spin density, qe: charge, me: mass, r: radius Know what happens (susceptibility wise) to Hg when it becomes oxygenated/deoxygenated correct answer: - Hemoglobin changes susceptibility from diamagnetic to paramagnetic as it becomes deoxygenated. - The oxygen binds with iron (III) in hemoglobin and pairs all electrons, making oxyhemoglobin diamagnetic.