Black blood late gadolinium enhancement using combined T₂ magnetization preparation and inversion recovery

Figure 1.a shows a schematic of the proposed sequence. A T₂prep pulse is inserted between the inversion pulse and the acquisition. Numerical simulation was conducted to simulate the effect of this pulse configuration on the signal intensity of healthy myocardium, blood, and infarcted myocardium assuming their T₁ to be 500, 350, and 200 ms respectively. Six healthy adult subjects and 2 patients with suspected scar (35±21 y, 4 males) were imaged using a 1.5T Philips scanner. A standard LGE sequence was used to acquire a stack of five 2D short-axis slices, and one long-axis slice 20 min after Gd-contrast injection with the following parameters: FOV = 320×320mm², slice gap = 5mm, in-plane resolution = 1.5×1.5 mm², slice thickness = 10mm, TR/TE = 6.2/3.0ms, α = 25°, SENSE rate = 2, acquisition window = 80 ms, NSA = 2, breath-hold = 8s per slice. Then, the proposed BB-LGE, with the same sequence parameters, was used to acquire the same slices while setting the sequence timing to the null point of both the normal myocardium and the blood pool. The BB-LGE was preceded by a short navigation scan to determine the timing parameters that achieve the perfect nulling of both blood and myocardium signals.

Figure 1b shows the numerical simulation for signal intensity in healthy myocardium, blood and infarct tissues using both regular LGE sequence, and the proposed BB-LGE for Δt₂=35ms. In the standard LGE sequence, there is no intersection that achieves a common null point for both myocardium and blood pool, while this null point can easily be obtained with the BB-LGE sequence. Figure 2 shows for the BB-LGE images examples in two healthy subjects (i.e. no infarct), and one patient with an infarction.