Treatment apparatus and treatment method

A treatment method, comprising:

• intravenously administering an antibody-photosensitive substance;
• inserting a treatment apparatus into a living body after 12 hours to 36 hours from the intravenous administration of the antibody-photosensitive substance, the treatment apparatus including a main shaft including a distal end portion and a proximal end portion, an inflation portion disposed distal of the main shaft and configured to be inflated by inflowing a fluid, a proximal end portion of the inflation portion is fixed to the distal end portion of the main shaft, an irradiation shaft accommodated in the main shaft, the irradiation shaft protruding from the distal end portion of the main shaft, passing through an inside of the inflation portion and extending beyond a distal end of the inflation portion so as to form a distal shaft that is a portion of the irradiation shaft protruding from the distal end of the inflation portion, and at least one irradiation unit including a light-emitting unit at a distal portion of the irradiation unit, the light-emitting unit configured to emit outward the excitation light of the antibody-photosensitive substance, and wherein the irradiation shaft includes an irradiation lumen that is closed at a most distal end of the irradiation shaft and opened at a most proximal end of the irradiation shaft, the irradiation lumen passing through the inside of the inflation portion to an inside of the distal shaft and configured to movably accommodate the irradiation unit, an insertion port for receiving the irradiation unit into the irradiation lumen is disposed on a proximal side of the irradiation shaft, the distal shaft includes the most distal end of the irradiation shaft, which closes a distal end of the irradiation lumen and protrudes distally relative to the distal end of the inflation portion by a predetermined protrusion length in a range of 10 mm to 50 mm, wherein an outer diameter of the distal shaft is smaller than a maximum outer diameter of the inflation portion when being inflated the inflation portion, wherein the light-emitting unit of the irradiation unit is configured to be disposed in a first portion of the irradiation lumen disposed on the inside of the inflation portion and a second portion of the irradiation lumen disposed on the inside of the distal shaft, so as to emit the excitation light of the antibody-photosensitive substance from the inflation portion and the distal shaft;
• inserting the distal shaft into a body lumen;
• inflating the inflation portion in the living body;
• emitting the excitation light from the distal shaft to a surrounding tissue;
• emitting the excitation light from the inflation portion to the surrounding tissue;
• and
• deflating the inflation portion.

A treatment method comprising:

• intravenously administering an antibody-photosensitive substance;
• inserting a treatment apparatus into a living body after the intravenous administration of the antibody-photosensitive substance, the treatment apparatus including a main shaft including a distal end portion and a proximal end portion, an inflation portion disposed distal of the main shaft and configured to be inflated by inflowing a fluid, a proximal end portion of the inflation portion is fixed to the distal end portion of the main shaft, an irradiation shaft accommodated in the main shaft, the irradiation shaft protruding from the distal end portion of the main shaft, passing through an inside of the inflation portion and extending beyond a distal end of the inflation portion so as to form a distal shaft that is a portion of the irradiation shaft protruding from the distal end of the inflation portion, and at least one irradiation unit including a light-emitting unit at a distal portion of the irradiation unit, the light-emitting unit configured to emit outward the excitation light of the antibody-photosensitive substance, and wherein the irradiation shaft includes an irradiation lumen that is closed at a most distal end of the irradiation shaft and opened at a most proximal end of the irradiation shaft, the irradiation lumen passing through the inside of the inflation portion to an inside of the distal shaft and configured to movably accommodate the irradiation unit, an insertion port for receiving the irradiation unit into the irradiation lumen is disposed on a proximal side of the irradiation shaft, the distal shaft includes the most distal end of the irradiation shaft, which closes a distal end of the irradiation lumen and protrudes distally relative to the distal end of the inflation portion by a predetermined protrusion length in a range of 10 mm to 50 mm, wherein an outer diameter of the distal shaft is smaller than a maximum outer diameter of the inflation portion when being inflated the inflation portion, wherein the light-emitting unit of the irradiation unit is configured to be disposed in a first portion of the irradiation lumen disposed on the inside of the inflation portion and a second portion of the irradiation lumen disposed on the inside of the distal shaft, so as to emit the excitation light of the antibody-photosensitive substance from the inflation portion and the distal shaft;
• inserting the distal shaft into a body lumen;
• inflating the inflation portion in the living body;
• and
• emitting the excitation light from the distal shaft and the inflation portion to surrounding tissue.