【大冰鮮奶茶無糖微冰】評論

(A) Tl-->0.693*T1(B)脂肪的零點（null point）時間<白質的零點時間(C) 脂肪壓抑STIR造影是利用較短反轉時間（TI），來抑制影像中脂肪的訊號-----STIR-->短Tl長TR

【Klose Liu】評論

Double inversion recovery (DIR) is a type of "black blood" technique useful for visualizing the walls of the cardiac chambers and blood vessels (including the coronary arteries).As the name implies, the sequence involves application of two RF-inversion pulses in close succession after an EKG trigger. The first inverting pulse is spatially non-selective, while the second pulse is spatially selective.  Dark blood double IR sequence. After the two inversion pulses, tissue within a slice is unaffected, but the magnetization of blood outside the slice is inverted. As this blood flows into the slice for imaging, it produces no signal since TI is chosen to be null its signal. The image acquisition module is typically 2D fast (turbo) spin echo.圖文出處: https://mriquestions.com/dark-blooddouble-ir.html