High-resolution contrast-enhanced MRI of atherosclerosis with digital cardiac and respiratory gating in mice.
Atherosclerosis initially develops predominantly at the aortic root and carotid origin, where effective visualization in mice requires efficient cardiac and respiratory gating. The present study sought to first compare the high-resolution MRI gating performance of two digital gating strategies using: 1) separate cardiac and respiratory signals (double-sensor); and 2) a single-sensor cardiorespiratory signal (ECG demodulation), and second, to apply an optimized processing technique to dynamic contrast-enhanced (CE) carotid origin vessel-wall imaging in mice. High-resolution MR mouse heart and aortic arch images were acquired by ECG signal detection, digital signal processing, and gating signal generation modeled using Simulink (MathWorks, USA). Double-sensor gating used a respiratory sensor while single-sensor gating used breathing-modulated ECG to generate a demodulated respiratory signal. Pre- and postcontrast T(1)-weighted images were acquired to evaluate vessel-wall enhancement with a gadolinium blood-pool agent (P792; Guerbet, France) at the carotid origin in vivo in ApoE(-/-) and C57BL/6 mice, using the optimized cardiorespiratory gating processing technique. Both strategies provided images with improved spatial resolution, less artifacts, and 100% correct transistor-to-transistor logic (TTL) signals. Image quality allowed vessel-wall enhancement measurement in all the ApoE(-/-) mice, with maximal (32%) enhancement 27 min postinjection. The study demonstrated the efficiency of both cardiorespiratory gating strategies for dynamic contrast-enhanced vessel-wall imaging.
Alsaid
Hasan
H
Université de Lyon, Lyon, F-69000, Université Lyon 1, Villeurbanne, France.
Sabbah
Maher
M
Bendahmane
Zakaria
Z
Fokapu
Odette
O
Felblinger
Jacques
J
Desbleds-Mansard
Catherine
C
Corot
Claire
C
Briguet
André
A
Crémillieux
Yannick
Y
Canet-Soulas
Emmanuelle
E
D000818:Animals; D016477:Artifacts; D050197:Atherosclerosis / Q000175:diagnosis*; D003287:Contrast Media; D004562:Electrocardiography / Q000379:methods*; D006339:Heart Rate; D006571:Heterocyclic Compounds; D007089:Image Enhancement / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009942:Organometallic Compounds; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted
D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C435266:contrast agent P792