time before data acquisition occurs (for sufficient T1 recovery). Since it saturates all the slices in the same manner, it will give more uniform suppression for all slices. Multi-planar imaging (short axis and long axis) is also possible in the same acquisition.
Sat pulse (used in FGRETC, SSFP)
S1 S2 H1 H2
S3 H3 H4
If a Non-selective Saturation pulse is used,
multi-planar prescription (short and long
axis) is allowed. This is desirable because
pathology at the apex can be missed if
only short axis slices are acquired. In
Timecourse imaging, there are usually
two types of temporal resolutions that
the user is concerned about.
Hard 90 Sat pulse
1 Temporal resolution of the
acquisition window, i.e., how much
time is needed to acquire a slice.
The shorter the acquisition window,
the less cardiac motion artifact
will be observed and the more
slice can be fit into an RR interval.
ASSET and shorter RF pulse
(200 us) are used to minimize
the acquisition window.
2 Temporal resolution of the time
curve sampling, i.e., how often a
slice is acquired (once per 1RR vs
once per 2RR). The user can
select the number of RR for each
acquisition. The lower the RR
(more frequent sampling), the
better the depiction of the contrast
enhancement time curve—but the
number of slices allowable will
Comparison of various GE Timecourse techniques
Max slices per 2RR
Notch or Sat
Notch : 9
MR Echo FGRE