Navigation device for use with a funnel catheter minimizing catching at a vessel bifurcation

A method for using an endovascular medical system to prevent catching at a vessel bifurcation during removal of a clot;

• wherein the endovascular medical system comprises:
• a funnel catheter having a proximal end and an opposite distal end defining a lumen therebetween;
• the funnel catheter having a radially expandable distal section including a distal edge;
• the radially expandable distal section of the funnel catheter being transitionable between a radially constricted state and a radially expanded state;
• and the radially expandable distal section of the funnel catheter while in the radially expanded state has a maximum inner diameter at the distal edge;
• and a navigation device advanceable in the lumen of the funnel catheter;
• wherein the navigation device comprises:
• a tapered distal section having a proximal end of maximum outer diameter and a distal end of minimum outer diameter;
• a proximal section;
• a radially expandable section interposed between the tapered distal section and the proximal section;
• the radially expandable section of the navigation device is transitionable between a radially constricted state and a radially expanded state;
• wherein in the radially constricted state, the radially expandable section of the navigation device has an outer diameter slidable within the lumen of the funnel catheter;
• and wherein in the radially expanded state, the radially expandable section of the navigation device has a maximum outer diameter substantially equal to the maximum inner diameter at the distal edge of the radially expandable distal section of the funnel catheter while in the radially expanded state;
• the navigation device further including a guidewire permanently secured to the tapered distal section, the guidewire having a distal portion projecting distally in a longitudinal direction beyond the distal end of the tapered distal section;
• the method comprising the steps of:
• navigating through the vasculature a guide catheter;
• while the radially expandable distal section is in the radially constricted state, pushing the funnel catheter through the guide catheter;
• upon exiting from a distal end of the guide catheter, the radially expandable distal section of the funnel catheter automatically transitioning to the radially expanded state;
• with the radially expandable distal section of the funnel catheter while in the radially expanded state maintained at a positioned on a proximal side of the vessel bifurcation, advancing through the lumen of the funnel catheter the navigation device while the radially expandable section of the navigation device is in a radially constricted state;
• substantially aligning the radially expandable section of the navigation device with the radially expandable distal section of the funnel catheter in the radially expanded state;
• with the substantial alignment of the radially expandable section of the navigation device and the radially expandable distal section of the funnel catheter in the radially expanded state, activating the radially expandable section of the navigation device substantially filling the maximum inner diameter at the distal edge of the radially expandable distal section of the funnel catheter while in the radially expanded state;
• advancing in a distal direction past without catching on the vessel bifurcation the funnel catheter together with the activated radially expandable section of the navigation device in the radially enlarged state substantially filling the inner diameter of the radially expandable distal section of the funnel catheter;
• after passing distally of the vessel bifurcation, deactivating the radially expandable section of the navigation device transitioning to the radially constricted state;
• while the radially expandable section of the navigation device is in the radially constricted state, withdrawing the navigation device via the lumen of the funnel catheter while the funnel catheter is maintained in position within the vasculature.