Comparison of Strategies for CSF and Blood Flow Motion Artifacts Suppression in T2-Weighted Spin-Echo MR Imaging of the Spine

Abstract

The cerebrospinal fluid flow void sign has previously been described (Sherman and Citrin 1986). This sign is related to the pulsatile and turbulent flow of cerebrospinal fluid through narrow areas of the ventricular system. When this occurs, CSF is visualized as a zone of hypointensity due to time of flight and spin dephasing effects. However, in evaluation of the spine, this sign tends to obscure interfaces between the discs and the thecal sac, as well as between the thecal sac and the spinal elements residing within the thecal sac. Reduction of the cerebrospinal fluid flow void sign can be affected by acquiring data in a fashion that is synchronized to the R-R interval of the heart or by the application of special gradients which reduce these moments of motion. We evaluated these two techniques in order to determine the most efficient way to perform T2-weighted imaging of the spinal canal.