Functional magnetic resonance imaging <unk>  of the<unk>  cord<unk>  is an adaptation of the<unk>  method that has been developed for use in the brain (1). Although the basic principles underlying the methods are the same,<unk>  requires a number of specific adaptations to accommodate the periodic motion of the<unk>  cord, the small cross-sectional dimensions (roughly 8 mm x 15 mm at the largest region), the length (~45 cm in adult humans), and the fact that the magnetic field that is used for MRI varies with position in the<unk>  cord because of magnetic susceptibility differences between bone and tissues.<unk>  has been used to produce maps of neuronal activity at most levels of the<unk>  cord in response to various stimuli, such as touch, vibration, and thermal changes, and with motor tasks. Research applications of<unk>  to date include studies of normal sensory and motor function, and studies of the effects of trauma to the<unk>  cord (1-3) and multiple sclerosis (4). Two different data acquisition methods have been applied, one based on the established BOLD (blood-oxygen-level dependent)<unk>  methods used in the brain, and the other based on SEEP (signal enhancement by extravascular water protons) contrast with essentially proton-density weighted spin-echo imaging (see MRI). The majority of the studies published to date are based on the SEEP contrast method. Methods demonstrated to overcome the challenges listed above include using a recording of the heart-beat to account for the related time course of<unk>  cord motion, acquiring image data with relatively high (~ 1-2 mm) spatial resolution to detect fine structural details, and acquiring images in thin contiguous sagittal slices to span a large extent of the<unk>  cord. Methods based on BOLD contrast have employed parallel imaging techniques to accelerate data acquisition, and imaging slices transverse to the<unk>  cord, in order to reduce the effects of spatial magnetic field distortions (5). Methods based on SEEP contrast have been developed specifically because they have low sensitivity to magnetic field distortions while maintaining sensitivity to changes in neuronal activity.
Spinal fMRI
Magnetic resonance myelography
Myelography
Cervicography
Magnetic resonance neurography
Brain mapping
Electromagnetic source imaging
Clinical neurophysiology