[Usefulness of phase-sensitive inversion recovery in delayed enhanced cardiac MRI].
BACKGROUND
Delayed-enhancement MRI is a technique that has significant clinical usefulness, particularly for myocardial viability determination in ischemic heart disease. Delayed enhanced images have been acquired by using the inversion recovery(IR)method. It is necessary for the IR method to select optimal inversion time(TI). Recently, the phase-sensitive inversion recovery(PSIR)method has been developed to detect Gd-DTPA enhanced myocardium.


OBJECTIVE
To compare the IR method with the PSIR method by acquiring Gd-DTPA solution phantoms A(0.05 mmol/l)and B(0.04 mmol/l)in various parameters.


METHODS
Images were acquired using a turbo-fast low angle shot(t-flash)sequence in each method.


RESULTS
The null point of signal intensity(SI)shortened as the flip angle(FA)and segments increased in the IR method. Excess segments also caused the duration of breath holding to be extended. The IR method might cause reversed SI between normal and Gd-DTPA enhanced myocardium if the optimal TI was not carefully selected. On the other hand, PSIR had no problem in obtaining phase-sensitive images that were converted into positive SI keeping inverse longitudinal magnetization. The PSIR method avoided the need to select optimal TI and loss of contrast.


CONCLUSIONS
The PSIR method was a useful sequence for delayed-enhancement MRI to detect Gd-DTPA enhanced myocardium.
Sugimori
Hiroyuki
H
Department of Radiological Technology, Asahikawa Medical College Hospital, Japan.
Sakamoto
Naka
N
Natori
Shunsuke
S
Yanagisawa
Akira
A
Uno
Takahiro
T
Kubota
Makoto
M
D003287:Contrast Media; D019786:Gadolinium DTPA; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017202:Myocardial Ischemia / Q000175:diagnosis; D009206:Myocardium / Q000473:pathology; D019047:Phantoms, Imaging
D003287:Contrast Media; D019786:Gadolinium DTPA