Breast MRI Using TWIST: Doubling the Spatial Resolution for Free

Rolf Janka¹, Evelyn Wenkel¹, Christian Geppert², Berthold Kiefer², Michael Uder¹

The TWIST sequence divides k-space in two radial regions and samples it using a pseudo-stochastic trajectory at adjustable density. While the central region is sampled at the full temporal resolution, the periphery is sampled with reduced density. Its main field of application is an increase of temporal resolution in MR-angiography. But it can also be used to increase spatial resolution in the dynamic sequence of breast MRI. We tested the new sequence in 61 women and think it is a reliable and powerful tool in breast imaging which fulfil the requirements of both high temporal and spatial resolution.