@InProceedings{Supelec497,
author = {Brice Fernandez and Julien Oster and Maélène Lohezic and Damien Mandry and Olivier Pietquin and Pierre-André Vuissoz and Jacques Felblinger},
title = {{Adaptive Trigger Delay Using a Predictive Model Applied to Black Blood Fast Spin Echo Cardiac Imaging in Systole}},
year = {2009},
booktitle = {{Proceedings of the 17th meeting of the International Society for Magnetic Resonance Medicine (ISMRM 2009)}},
pages = {4719},
month = {April},
address = {Honolulu (Hawaii, USA)},
abstract = {In clinical applications, cardiac gated sequences are commonly
used for heart imaging. In practice, we simply wait a fixed
time called Trigger Delay
(TD) after the R-wave has been detected to acquire data in the
chosen cardiac phase. The main problem of this method is that
the TD is constant and does not take into
account the physiological variability such as instantaneous
heart rate changes during breath-hold or free breathing.
Another issue is that we cannot use a TD shorter
than the preparation time. Consequently when a cardiac gated
sequence with a long preparation time is used, only diastolic
images are achievable. Double Inversion
Recovery Fast Spin Echo (DIR-FSE), resulting in black-blood
images of the heart [1], is such a sequence since the inversion
time (TI) needed to cancel the blood signal
is around 500ms. Systolic view of the heart could also be of
clinical interest, especially during end-systolic phase when
the cardiac volume is minimum and constant
(average TD = 300ms, average duration 60ms [2]). The primary
aim of this work was to assess a robust method to acquire black
blood FSE in end-systolic phase. For
this purpose, the DIR preparation has to be launched before the
R-wave in the previous cardiac cycle. A RR interval prediction
is then needed and heart rate variability
has to be accounted in order to position the acquisition window
properly. A new general adaptive method is described here that
overcomes the above listed limitations
in prospectively cardiac gated sequences with long preparation
time using a predictive model. This method has been applied on
end-systolic black blood FSE images.}
}