Method and apparatus for centering a microcatheter within a vasculature

A method of centering a microcatheter in vessel comprising:

• inserting a microcatheter into vessel, wherein the microcatheter comprises
• a hollow shaft with a distal end and a proximal end,
• a non-occluding self-expandable scaffold having a central longitudinal axis, the self-expandable scaffold being disposed at the distal end of the catheter, wherein a portion of the distal end of the catheter is disposed at least in part inside the self-expandable scaffold, and
• a sheath
• wherein the distal end is slidable along the shaft,
• wherein the scaffold is configured to be coupled to the distal end of the catheter, wherein at least a portion of the distal end of the catheter is disposed substantially along the central axis of the self-expandable scaffold structure,
• wherein the hollow shaft is covered by the sheath;
• and
• withdrawing the sheath to expand the self-expandable scaffold structure whereby expansion of the scaffold centers the microcatheter along the central longitudinal axis of the scaffold thereby centering the microcatheter in the vessel.