[Contrast in nuclear magnetic resonance imaging].

It has been shown that signal strength from nuclear resonance and grey scale in NMR depend on pulse sequence, pulse repetition interval, delay time, tissue-dependent parameters, such as relaxation times T1 and T2, proton density, and flow movements. The relative grey scales for tissues using varying pulse sequences can be predicted mathematically. These relationships are shown graphically to indicate to the user the effect of pulse repetition, processing time and T1 and T2.