[Gated Radiotherapy]
Recent external radiotherapy requires precise localization of the target because advance in diagnostic imaging has made it possible to visualize a tiny tumor which would be curable with focused high dose irradiation. However, tumors in respiratory and bowel organs have been difficult to be given the high dose because of 1 to 3 cm movement during delivery of irradiation. Respiratory-gating techniques have been used with medical linear accelerators and particle therapy machines. Real-time tumor-tracking radiotherapy has been realized using fluoroscopic x-rays, internal gold-markers, and pattern recognition technology. Advantage and disadvantage of each gating technique have been realized. Active breath control method would be a cost-effective way of precise treatment without gating. More work is required to find the relationship between abdominal wall and internal movement of the tumor in many respiratory-gating radiotherapy and between the internal markers and target volume in real-time tracking radiotherapy.
Shirato
Hiroki
H
Department of Radiology, Hokkaido University Hospital.
Onimaru
Rikiya
R
Kitamura
Kei
K
Watanabe
Yoshiharu
Y
Furuya
Teruo
T
Fujita
Katsuhisa
K
Nangumo
Junya
J
Oda
Makoto
M
Oita
Masataka
M