Method of making an enhanced flexibility neurovascular catheter

A method of making a flexible distal zone on a neurovascular catheter, having an elongate tubular body with a distal end, comprising the steps of:

• dip coating a removable mandrel to form a tubular inner layer on the mandrel;
• coating the tubular inner layer with a tie layer;
• applying a helical coil to the outside of the tie layer;
• positioning a plurality of tubular segments over the helical coil, the plurality of segments having durometers that decrease in a distal direction, wherein the plurality of tubular segments form a proximal section having a proximal end and a distal end and a durometer equal to or greater than 65D at all points along a length from the proximal end to the distal end of the proximal section, a distal section having a proximal end and a distal end and a durometer equal to or less than 35D at all points along a length extending from the proximal end to the distal end of the distal section, and a transition section extending from the distal end of the proximal section to the proximal end of the distal section, the transition section comprising at least two tubular segments and having a durometer less than 65D and greater than 35D at all points along a length extending from the distal end of the proximal section to the proximal end of the distal section, the transition section being shorter in length than the proximal section and shorter in length than the distal section;
• heating the tubular segments to form the flexible distal zone on the neurovascular catheter;
• and
• removing the mandrel.