A method for correctly setting the rf flip angle.

摘要: Currently the accepted method for setting correct rf power levels to achieve 90° and 180° pulses MR imaging is peak echo amplitude of a spin-echo sequence. The this α-2α pulse sequence proportional sin3(α) has relatively broad maximum. Recently another flip angle by maximizing ratio stimulated primary amplitudes (in 3α sequence) demonstrated accuracy similar that using shorter repetition time. We present new, more sensitive, accurate pulses. In method, based upon sequence, we are able accurately set within ±0.1 dB minimizing signal third spin echo. This null works both selective nonselective or 180°, allowing user adjust relative four types single © 1989 Academic Press, Inc.