A method is disclosed for collecting substances inside a living body lumen using a medical device having an elongated shaft, a filter portion, and a support portion. The method includes inserting the medical device into the living body lumen inserting an atherectomy device through the elongated shaft of the medical device scraping a substance with the atherectomy device collecting the substance using the filter portion of the medical device and aspirating the substance by an aspiration catheter while the aspiration catheter is moved forward and rearward relative to the filter portion inside the filter portion.