Purpose: To design and compare an eight-channel phased array (PA) coil for carotid imaging to an established four-channel PA design at 3T.
Materials and methods: An eight-channel PA (8PA) coil was designed specifically for imaging the carotid bifurcation and compared with the existing four-channel (4PA) design using a phantom and by in vivo black-blood magnetic resonance imaging (MRI). The 8PA and 4PA were compared in terms of coverage, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR).
Results: The 8PA showed up to 1.7-fold improvement in SNR at a depth of 3.5 cm and greater longitudinal coverage at a given SNR on a phantom. The 8PA showed improved vessel wall SNR for high spatial resolution (0.63 mm(2)) PD, T1, and T2 (1.7, 1.7, 1.6 times, respectively; P <or= 0.002) and improved CNR (1.7, 1.6, 1.5 times, respectively; P <or= 0.002). Ultrahigh-resolution (0.27 mm(2)) T1-weighted images showed better SNR and CNR (1.4 times, P <or= 0.0001) on 8PA compared to 4PA.
Conclusion: Carotid imaging studies may benefit from the improved SNR and larger coverage provided by use of the 8PA.