A 3D MRI sequence for computer assisted surgery of the lumbar spine

The aim of this research was to develop a magnetic resonance (MR) sequence capable of producing images suitable for use with computer assisted surgery (CAS) of the lumbar spine, These images needed good tissue contrast betwee n bone and soft tissue to allow for image segmentation and generation of a 3D-surface model of the bone for surface registration. A 3D double echo fas t gradient echo sequence was designed. Images were filtered for noise and n onuniformity and combined into a single data set. Registration experiments were carried out to directly compare segmentation of MR and computed tomogr aphy (CT) images using a physical model of a spine. These experiments showe d the MR data produced adequate surface registration in 90% of the experime nts compared to 100% with CT data. The MR images acquired using the sequenc e and processing described in this article are suitable to be used with CAS of the spine.