Increasing spoiling efficiency in RF-spoiled gradient echo sequences by averaging of RF phase-cycle-adapted k-spaces.

نویسندگان

  • Jochen Leupold
  • Jürgen Hennig
چکیده

A method is presented that improves the effectiveness of RF-spoiling whenever an image consists of the averaging of several identical single acquisitions. Using this method, it becomes possible to reduce the necessary moment of the spoiler gradient by a factor equal to the number of averages. The idea is to perform the collection of k-space lines such that the averaging takes over a part of the spoiling process. The number of sequence cycles played out between two acquisitions of a certain k-space line is adjusted based on both the number of total averages of this line and the phase-cycling pattern of the RF-pulse train of a RF-spoiled gradient echo sequence. In this way, ghost artifacts visible in the single images add to zero in the averaged image while the depiction of the object experiences normal averaging with enhanced signal-to-noise ratio.

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عنوان ژورنال:
  • Magnetic resonance in medicine

دوره 66 4  شماره 

صفحات  -

تاریخ انتشار 2011