Anomalous Noise Behaviour in ZTE Imaging

Markus Weiger^1,2, Klaas Paul Pruessmann³

ZTE is an MRI technique with 3D radial centre-out encoding and zero echo time, particularly suited for imaging samples with short T2. ZTE data is inherently incomplete in the k-space centre, which can be addressed by algebraic reconstruction. In this work, a noise analysis of ZTE imaging is presented, revealing peculiar and specific mechanisms of noise amplification and correlation, which lead to an artefact-like manifestation of noise in the intermediate 1D images. However, it is also shown that the strong noise averaging in central k-space inherent to 3D radial scanning compensates for this effect, thus making remarkably large acquisition gaps feasible.