Microcatheter for delivering asubstance (e.g., infusion agent including embolizationmaterial and/or contrast enhancing material) in a smallblood vessel towards a target bodily part. Includes asingle lumen surrounded by tubular wall having outerdiameter and opened at both ends； tubular wallproximal portion is connectable to a pressure source andreservoir containing infusion agent, and tubular walldistal portion ends with a tip； the tubular wall distalportion includes an infusion agent flow disruptionsection configured to disrupt passage therethrough ofincoming retrograded flow of infusion agent, duringcontinuous delivery of infusion suspension from thereservoir to the tip. Disclosed are methods using themicrocatheter for performing local embolization in asmall blood vessel feeding a (for example, cancerous)target bodily part, and for delivering infusion agent ina small blood vessel towards such target bodily part.Also disclosed are devices and methods for filteringnon-target infusion agent.
