An interventional instrument (24) for use in assessing a blockage of fluid flow of the interventional instrument during an interventional procedure, the interventional instrument including: a balloon (30) disposed proximate to a tip of the interventional instrument that inflates and anchors in a lumen of a fluid conduit during the interventional procedure and one or more susceptibility markers (34) disposed proximate to the tip of the interventional instrument. A magnetic resonance scanner (10) is configured to image at least the tip of the interventional instrument during the interventional procedure for obtaining a magnetic resonance image in which fluid flow (40) through the fluid conduit past the inflated balloon produces an extended magnetic resonance image artifact (42).
