Black blood gradient echo cine magnetic resonance imaging of the mouse heart

Abstract

A black blood gradient echo sequence for multiphase cardiac MRI of the mouse heart was implemented on a 4.7-T scanner and compared to a conventional bright blood sequence. Black blood was achieved using the double inversion recovery technique. Ten mice were imaged using both the bright and the black blood sequences, and 2 of the mice were additionally imaged using bright and black blood sequences modified to perform myocardial tagging. Manual planimetry of the images was performed by two independent observers to detect the endocardial and epicardial borders and subsequently to compute chamber volumes and myocardial mass. Weight of the excised left ventricle was used as a gold standard for myocardial mass. Bland-Altman analysis demonstrated reduced interobserver variability for the measurement of cardiac volumes using the black blood sequence compared to the bright blood sequence (95% confidence interval was ؊0.89 -0.73 L for black blood versus ؊1.86 -1.28 L for bright blood). Also, Bland-Altman analysis showed that the black blood sequence provides improved accuracy for the measurement of myocardial mass compared to the bright blood sequence (average difference between MRI versus weight was 0.9 g for black blood and ؊11.2 g for bright blood, P < 0.01).

Cardiac magnetic resonance imaging in small rodents using clinical 1.5T and 3.0T scanners

“…Steady-state free precession imaging (26) has recently been adopted for clinical cine imaging, because it achieves high SNR and excellent contrast between myocardium and the blood pool; however, this technique has yet to be modified for small rodent imaging. Furthermore, black-blood cine imaging was recently reported in mice (27), but this technique has not been implemented on any clinical scanners, yet. Spiral imaging has recently been demonstrated for small rodent CMR (28).…”

Borderzone Contractile Dysfunction Is Transiently Attenuated and Left Ventricular Structural Remodeling Is Markedly Reduced Following Reperfused Myocardial Infarction in Inducible Nitric Oxide Synthase Knockout Mice

“…For LV volumes, an ECG-triggered 2-dimensional (2D) double inversion recovery black-blood cine sequence (13) was used to obtain 7 to 8 contiguous 1-mm-thick short-axis slices from apex to base. Imaging parameters included: echo time 3.2 ms, repetition time 8 to 10 ms, flip angle 20°, field of view 2.56 ϫ 2.56 cm 2 , matrix 128 ϫ 128, and 14 to 16 phases per cardiac cycle.…”

2093 CMR reveals that cardiac-specific overexpression of the inducible form of nitric oxide synthase induces Left Ventricular Hypertrophy in wild-type mice after AAV-Mediated direct gene transfer

“…Another 5 untreated C57Bl/6 mice served as agematched controls. CMR was performed at the end of sepiapterin treatment to assess the impact of iNOS overexpression using a 4.7 T Varian system and a black-blood pulse sequence as described [2]. Excised hearts from the control and AcTnTiNOS-treated groups were immunostained for iNOS and for cleaved caspase III (a sensitive marker of apoptosis).…”