A needle catheter for scraping or thrombosing vascular walls has a sleeve mounted fast to a needle. The sleeve has a recess in which an inflatable balloon is mounted. The balloon may be selectively inflated and deflated by means of an extra-corporeal syringe. The balloon carries a plurality of abrasive burrs or ribs on the outer surface. After insertion, either subcutaneously or intravascularly, the balloon may be selectively inflated, after which the catheter may be moved longitudinally therealong to scrape or thrombose the walls of the vessel.