Intrathecal (IT) Baclofen Drug Distribution

While ITB therapy is commonly recommended for treatment of severe spasticity due to a variety of diseases, the location of optimal drug (baclofen) delivery has not been defined in a controlled study. Furthermore, the cost of pharmacological management in these patients is significant, and optimal location for drug delivery through an implantable drug pump may have significant impact on the cost burden of maintenance refills. It is the goal of this pilot study to determine whether there is a significant therapeutic advantage to place the ITB catheter within the cervical, thoracic or lumbar region of the spine. It is also a goal of this pilot study to determine whether the origin of spasticity influences the effect of Lioresal Intrathecal (baclofen injection) on ITB catheters located in the cervical, thoracic or lumbar regions of the spine. The investigators propose to study the impact of catheter location on the reduction in spasticity within a group of patients who are scheduled for ITB trial. In studying the impact of catheter location among patients with spinal versus cerebral origin of spasticity, the disease origin may also have a significant impact on baclofen dosing relative to the placement of the catheter. In addition, the pharmacokinetic half-life and the variability of intrathecal baclofen is poorly understood as data is limited. In order to provide initial data regarding CSF baclofen washout, samples of spinal fluid obtained just prior to- and following IT baclofen administration will be obtained for delayed analysis. The results of these pharmacological analysis may refine the understanding of how quickly baclofen is distributed from a given catheter location, and whether it is affected by catheter location or disease origin. Since multiple catheter locations will be studied within a given patient, it also affords the opportunity to sample small amounts of CSF at key anatomical sites along the spinal axis as a secondary objective.