A flexible five-channel shielded-coaxial-cable (SCC) transceive neck coil for high-resolution carotid imaging at 7T

Abstract

Purpose: Imaging the carotid arteries at 7T ideally requires a flexible multichannel array that allows B1-shimming and conforms to different neck sizes. The major challenge is to minimize coupling between closely spaced coils and to make the coupling relatively insensitive to loading conditions. Methods: We have designed a five-channel flexible transceive array composed of shielded-coaxial-cable coils placed on the anterior part of the neck and conforming to the anatomy. In vivo imaging of the carotid arteries in three subjects has been performed. Results: The measured noise correlation matrices show the decoupling level between the individual elements to be −12.5 dB and better. Anatomical localizer imaging of the carotids shows both carotids in every subject well visualized after B1-shimming. In vivo black-blood, carotid images were acquired with very high in-plane spatial resolution (0.25 × 0.25 mm2) with clear depiction of the vessel walls. Conclusions: The flexibility of the proposed coil has been demonstrated by imaging subjects with different neck circumferences. To the best of our knowledge, the in-plane resolution of 0.25 × 0.25 mm2 is the highest reported at 7T.