Abstract: A medical device and treatment method for treating veins. The medical device includes: an elongated outer sheath; an inner member extending through inside of the outer sheath, the inner member protruding distally beyond the outer sheath; an expansion portion positioned between a distal portion of the outer sheath and a distal portion of the inner member, the expansion portion having a plurality of linear material portions extending along an axial direction of the inner member, the expansion portion being expandable in a radial direction of the inner member; a biasing member disposed inside the outer sheath biasing the inner member proximally relative to the outer sheath; and a fixing portion configured to fix the relative positions of the inner member and the outer sheath in a state in which the expansion portion has been expanded. The fixing portion is also configured to be released from the fixed state.

Abstract: A blood vessel treatment method including inserting a medical device into a blood vessel, the medical device including an elongate shaft portion and a contact portion configured to contact a biological tissue in the blood vessel; bringing the contact portion into contact with the biological tissue in the blood vessel; twisting the blood vessel by moving the contact portion; and releasing a treatment agent from the medical device for occluding or contracting a lumen of the blood vessel.

Abstract: A medical device and treatment method for treating veins. The medical device includes: an elongated outer sheath; an inner member extending through inside of the outer sheath, the inner member protruding distally beyond the outer sheath; an expansion portion positioned between a distal portion of the outer sheath and a distal portion of the inner member, the expansion portion having a plurality of linear material portions extending along an axial direction of the inner member, the expansion portion being expandable in a radial direction of the inner member; a biasing member disposed inside the outer sheath biasing the inner member proximally relative to the outer sheath; and a fixing portion configured to fix the relative positions of the inner member and the outer sheath in a state in which the expansion portion has been expanded. The fixing portion is also configured to be released from the fixed state.

Abstract: A method of treating a varicose vein involves inserting the distal portion of an intraluminal device into a varicose vein, wherein the device includes an elongated outer sheath and an expandable expansion member at the distal end of the outer sheath. The method also involves relatively moving the distal and proximal ends of the expandable spiral expansion member to reduce the distance between the distal and proximal ends of the expansion member and cause the expansion member positioned inside the varicose vein to outwardly expand to an expanded expansion member comprising a plurality of contact members in contact with the inner wall of the varicose vein. The method further includes axially moving the expanded expansion member while the contact members are in contact with the inner wall of the varicose vein and rotating the expanded expansion member during the axial movement.

Abstract: A method of treating a varicose vein involves inserting the distal portion of an intraluminal device into a varicose vein, wherein the device includes an elongated outer sheath and an expandable expansion member at the distal end of the outer sheath. The method also involves relatively moving the distal and proximal ends of the expandable spiral expansion member to reduce the distance between the distal and proximal ends of the expansion member and cause the expansion member positioned inside the varicose vein to outwardly expand to an expanded expansion member comprising a plurality of contact members in contact with the inner wall of the varicose vein. The method further includes axially moving the expanded expansion member while the contact members are in contact with the inner wall of the varicose vein and rotating the expanded expansion member during the axial movement.

Abstract: A method of treating a varicose vein involves inserting the distal portion of an intraluminal device into a varicose vein, wherein the device includes an elongated outer sheath and an expandable expansion member at the distal end of the outer sheath. The method also involves relatively moving the distal and proximal ends of the expandable spiral expansion member to reduce the distance between the distal and proximal ends of the expansion member and cause the expansion member positioned inside the varicose vein to outwardly expand to an expanded expansion member comprising a plurality of contact members in contact with the inner wall of the varicose vein. The method further includes axially moving the expanded expansion member while the contact members are in contact with the inner wall of the varicose vein and rotating the expanded expansion member during the axial movement.