Intravascular device such as introducer sheath or balloon catheter or the like and methods for use thereof

A method for sequentially dilating and then imaging a region of a subject:

• using an ultrasound probe, a guidewire, and a catheter, wherein the catheter comprises an elongate flexible member having a lumen in its distal length, a dilation balloon attached to the distal length, the outside of the distal length and balloon being sized for passage into the region of the subject and the lumen having a diameter sized to accept either the guidewire or the ultrasound probe, wherein the lumen splits into a dual lumen proximal of said balloon, the dual lumen comprising a guidewire lumen sized to accept the guidewire and a probe lumen sized to accept the ultrasound probe, the flexible member further comprising a third lumen wherein the third lumen communicates with the balloon, the method comprising the steps of:
• advancing the guidewire through the subject until a distal tip of the guidewire is distal of the region of the subject to be imaged;
• advancing the catheter through the distal lumen and the guidewire lumen, until the balloon has passed into the region to be dilated;
• inflating and then deflating the balloon by flowing a fluid through the third lumen;
• pulling the guidewire proximally, and leaving the distal tip of the guidewire within the wire lumen;
• advancing the ultrasound probe tip into the distal lumen portion of the catheter;
• preventing the ultrasound probe from extending distally beyond the catheter;
• and
• activating the probe to obtain post-dilation ultrasound images of the region.

A method of imaging and dilating a region of a lumen in a subject comprising the steps of:

• positioning a guidewire so that the distal tip of the guidewire is within the lumen and distal of a region of the lumen to be imaged and dilated;
• advancing a catheter using the guidewire as a guidance device until a distal end of the catheter is within the lumen, and distal of the region of the lumen to be imaged and dilated;
• retracting the guidewire until it becomes proximal of the region of the lumen to be imaged and dilated;
• advancing an ultrasound probe within the catheter until the tip is within the region of the lumen to be imaged and dilated;
• preventing the ultrasound probe from extending distally beyond the catheter;
• activating the probe to obtain images;
• advancing the catheter using a method comprising the steps of:
• retracting the probe, advancing the guidewire, and moving the catheter distally using the guidewire as a guidance device until a balloon dilation portion of the catheter is within the region to be imaged and dilated;
• and
• dilating the region of the lumen in the subject by temporarily inflating the balloon through a catheter lumen.