The disclosed methods and devices utilize various techniques to detach the distal end of a catheter from an obstruction with minimal invasiveness and effort by the surgeon. As reflux of an embolic agent or hardening material over the catheter tip is a major causative factor in the increased morbidity/mortality of embolization procedures and also a technical limitation preventing a better cure rate, a method has been developed for the detachment of the distal end of catheters within the body, preferably with no regard to the amount of reflux, and preferably at the proximal edge of the reflux, in order to be able to make embolization procedures safer and more effective.