Revised Scaling Relationship for Backflow Distance Along an Infusion Catheter

Convection-enhanced delivery (CED) is a means to deliver therapeutic agents directly into brain tissue for the treatment of brain tumors and other disorders of the central nervous system, such as Parkinson’s disease. Recent clinical trials have shown limited efficacy of this procedure, with poor distribution of the infused agent being the primary obstacle [1]. One of the challenges with improving the distribution is the effect of backflow, in which the infused fluid preferentially flows along the outside of the catheter toward the surface of the brain rather than through the tissue toward the desired region for delivery.