Methods and systems for treatment of acute ischemic stroke

A suction catheter system comprising:

• a guide catheter comprising a tubular shaft with a central lumen having an inner diameter, a proximal end and a distal opening, and a proximal section operably connected with the proximal end of the tubular shaft and having fittings that connect to a suction device;
• and
• a suction extension comprising a proximal portion, a suction tip comprising a distal opening and extending from the proximal portion in a distal direction, and a control structure connecting the proximal portion with the proximal section of the guide catheter, the suction tip having a distal inner diameter that is between about 0.035″ and about 0.095″ and the central lumen inner diameter is between about 0.065″ and about 0.120″, wherein the proximal portion is configured to slide within the central lumen of the tubular shaft to change the relative position of the proximal portion within the central lumen and provide for at least a portion of the narrow diameter suction extension to extend outward from the distal opening of the tubular shaft at appropriate configurations of the proximal portion, wherein an effective seal is formed by a tight fit between the proximal portion and the central lumen of the guide catheter and wherein the suction extension has a length from about 10 centimeters (cm) to about 25 centimeters (cm),
• wherein a suction lumen is formed extending from the fitting configured to connect to the suction device through a portion of the central lumen, the proximal portion and the suction tip to a distal opening.