To avoid artifacts that would otherwise occur from these repeated disruptions, the technique uses a radial k-space trajectory with equidistant view angles. The steady-state magnetization undergoes gradient and radiofrequency (RF) spoiling after each block of bSSFP modules (5 to 8 in this study) to suppress off-resonant and out-of-slice spins. Cine FISSįISS differs from conventional bSSFP in that it disrupts the steady-state magnetization at frequent intervals. Following standard localizer scans, breath-hold cine images were acquired in the left ventricular (LV) 2-chamber, 3-chamber, and 4-chamber views, as well as obliquely through the aortic valve. Eight healthy subjects (5 male, age = 24 to 54 years) were imaged at 1.5 T (MAGNETOM Avanto, Siemens Healthineers, Erlangen, Germany). The study was IRB-approved, and subjects provided written informed consent. Given its advantageous properties, we further hypothesized that the cine FISS technique, in combination with arterial spin labeling (ASL), could provide an alternative to phase contrast for visualizing and quantifying in-plane flow within the aorta and branch vessels.

The technique was compared to standard Cartesian cine bSSFP in a small group of healthy subjects to evaluate cardiac function, coronary artery conspicuity, and aortic valve morphology. We hypothesized that a prototype cine imaging technique, radial fast interrupted steady-state (FISS), could overcome these limitations.

Alternatively, cine sGRE suffers from inferior signal-to-noise ratio and temporal resolution, as well as considerable in-plane flow saturation. Cine bSSFP is also susceptible to artifact from rapid through-plane flow and banding artifact from off-resonance effects. As a result, small-caliber embedded structures such as the coronary and internal mammary arteries are obscured by artifacts from fat/water chemical shift. For instance, fat appears bright with cine bSSFP. In addition, preliminary results suggest that cine FISS ASL provides a potential alternative to phase contrast techniques for in-plane flow quantification, while enabling an efficient, visually-appealing, semi-projective display of blood flow patterns throughout the course of an artery and its branches.Įxisting cine imaging techniques for the cardiovascular system rely on balanced steady-state free precession (bSSFP) or spoiled gradient-echo (sGRE) readouts, each of which has significant limitations. The main drawback is a slight (~ 20%) decrease in temporal resolution.

ConclusionĬine FISS demonstrates several benefits for cardiovascular imaging compared with cine bSSFP, including better suppression of fat signal and reduced artifacts from through-plane flow and off-resonance effects. In healthy subjects, dynamic flow patterns were well visualized in the aorta, coronary and renal arteries using cine FISS ASL, even when the slice was substantially thicker than the vessel diameter. Banding artifacts in the subcutaneous tissues were reduced. Compared with cine bSSFP, cine FISS demonstrated a marked decrease in fat signal which improved conspicuity of the coronary arteries, while suppression of through-plane flow artifact on thin-slice cine FISS images improved visualization of the aortic valve. There was no significant difference in biplane left ventricular ejection fraction or cardiac image quality between the two techniques. Breath-hold cine FISS and bSSFP were acquired using similar imaging parameters. The study was IRB-approved and subjects provided consent. Given its advantageous properties, we further hypothesized that the cine FISS technique, in combination with arterial spin labeling (ASL), could provide an alternative to phase contrast for visualizing in-plane flow patterns within the aorta and branch vessels. The technique was compared with standard cine bSSFP for cardiac function, coronary artery conspicuity, and aortic valve morphology. We hypothesized that a prototype cine technique, radial fast interrupted steady-state (FISS), could overcome these limitations. For instance, with bSSFP, artifacts occur from rapid through-plane flow and off-resonance effects.

Existing cine imaging techniques rely on balanced steady-state free precession (bSSFP) or spoiled gradient-echo readouts, each of which has limitations.

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