Enhanced ultrasound visualization of intravascular devices

Abstract

Methods and devices for providing improved ultrasound visibility of medical devices intended for intravascular use are described. The inclusion of gas/solid boundary regions within a medical devices improves the resolution of the device under ultrasound visualization. Gas/solid boundary regions may be provided through the use of embedded gas-filled microlumens, microwells, or enclosed pockets within the medical device.

1 - 12 . (canceled) 
     
     
         13 . A medical device for use under ultrasound visualization, the medical device comprising:
 an elongate shaft comprising an outer surface and an inner surface defining an inner lumen,   wherein the elongate shaft comprises expanded polytetrafluoroethylene containing enclosed gas pockets to increase the visibility of the medical device under ultrasound imaging, and   wherein the expanded polytetrafluoroethylene is in one of (a) a closed cell configuration or (b) an open cell configuration having an enclosing sheath.   
     
     
         14 . The medical device of  claim 13 , wherein the expanded polytetrafluoroethylene is in the closed cell configuration. 
     
     
         15 . The medical device of  claim 13 , wherein the expanded polytetrafluoroethylene is in the open cell configuration, and wherein the medical device comprises the enclosing sheath. 
     
     
         16 . The medical device of  claim 13 , wherein the enclosed gas pockets are disposed randomly between the outer surface and the inner surface of the elongate shaft. 
     
     
         17 . The medical device of  claim 13 , wherein the enclosed gas pockets are irregularly distributed within the elongate shaft. 
     
     
         18 . The medical device of  claim 13 , wherein the enclosed gas pockets are disposed in a regular pattern within the elongate shaft. 
     
     
         19 . The medical device of  claim 13 , wherein the enclosed gas pockets are disposed uniformly along a length of the elongate shaft. 
     
     
         20 . The medical device of  claim 13 , wherein the enclosed air pockets are isolated and spaced apart from the inner lumen of the elongate shaft. 
     
     
         21 . The medical device of  claim 13 , wherein the enclosed gas pockets comprise a width of approximately 0.1 micrometers (μm) to approximately 300 μm. 
     
     
         22 . The medical device of  claim 13 , wherein the enclosed gas pockets comprise a width of approximately 1 micrometers (μm) to approximately 50 μm. 
     
     
         23 . The medical device of  claim 13 , wherein the enclosed gas pockets comprise a width of approximately 5 micrometers (μm) to approximately 10 μm. 
     
     
         24 . The medical device of  claim 13 , wherein the enclosed gas pockets contain air. 
     
     
         25 . The medical device of  claim 13 , wherein the elongate shaft comprises a diameter of from 3 French to 7 French. 
     
     
         26 . The medical device of  claim 13 , wherein the elongate shaft comprises a length of about 25 centimeters (cm) to about 100 cm. 
     
     
         27 . The medical device of  claim 13 , wherein the elongate shaft is configured to enable a flow of an adhesive material through the inner lumen. 
     
     
         28 . The medical device of  claim 13 , wherein the elongate shaft is configured to at least one of couple to or extend from a syringe configured to dispense a vein-occluding substance. 
     
     
         29 . The medical device of  claim 13 , wherein the enclosed gas pockets comprise gas-filled microspheres. 
     
     
         30 . A system for dispensing a vein-occluding substance, the system comprising:
 an elongate shaft comprising an outer surface and an inner surface defining an inner lumen, wherein the elongate shaft comprises expanded polytetrafluoroethylene containing enclosed gas pockets to increase the visibility of the medical device under ultrasound imaging, and wherein the expanded polytetrafluoroethylene is in one of (a) a closed cell configuration or (b) an open cell configuration having an enclosing sheath; and   a syringe configured to couple to the elongate shaft, the syringe configured to dispense the vein-occluding substance into the inner lumen of the elongate shaft.   
     
     
         31 . The system of  claim 30 , further comprising the vein-occluding substance.