Supraaortic CE MRA with SENSE at 3 Tesla

Purpose: To test the feasibility of contrast-enhanced MR angiography of the supraaortic arteries with SENSE and CENTRA at 3.0T

Methods: Contrast-enhanced (CE) MRA of the supraaortic arteries with randomly sampled central k-space (CENTRA) and SENSE was implemented on a clinical whole body 3.0T MR system (Achieva, Philips Medical Systems, Best, NL) using a 16-element, 8-channel neurovascular coil (Philips Medical Systems, Best, NL). CE MRA protocols were created using SENSE reduction factors (RF) ranging from 1 to 4. A 512×512 matrix was acquired over a 320 to 350mm FOV with 0.98 and 0.90mm thin slices (0.49 and 0.45mm over contiguous) yielding a sub-millimetre spatial resolution ranging of 0.63×0.63×0.90 to 0.68×0.68×0.98mm³ (true voxel) as compared to 0.81×0.81×1.0mm³ without SENSE acceleration (RF=1). Acquisition time was reduced from 2:09min. (RF=1) to 1:37 and 1:24min. (RF 2 and RF 4), respectively, while increasing the number of slices substantially from 150 slices (RF=1) up to 365 slices (RF=4).

Results: Despite of shorter acquisition times, the added number of slices (i.e. bigger scan volume) and the higher spatial resolution in the SENSE acquisitions (RF=2–4) allowed for visualization of vascular structures of the head and neck arteries that were not covered by standard protocol without SENSE acceleration (RF=1). In addition, the increased scan volume simplified the planning of the sequence and potentially helps to cover the distal portions of the vertebral arteries (V3– V4 segments) as well as the peripheral segments of the intracranial arteries.

Conclusion: Supraaortic CE MRA with SENSE RF 4 is clinical feasible at 3.0T and a very useful technique to provide additional anatomic information and higher spatial resolution while reducing acquisition time.