COMPARISON OF THE PERIPHERAL DOSES FROM DIFFERENT IMRT TECHNIQUES FOR PEDIATRIC HEAD AND NECK RADIATION THERAPY.
Intensity-modulated radiation therapy (IMRT) can deliver high and homogeneous doses to the target area while limiting doses to organs at risk. We used a pediatric phantom to simulate the treatment of a head and neck tumor in a child. The peripheral doses were examined for three different IMRT techniques [dynamic multileaf collimator (DMLC), segmental multileaf collimator (SMLC) and volumetric modulated arc therapy (VMAT)]. Peripheral doses were evaluated taking thyroid, breast, ovary and testis as the points of interest. Doses were determined using a radio-photoluminescence glass dosemeter, and the COMPASS system was used for three-dimensional dose evaluation. VMAT achieved the lowest peripheral doses because it had the highest monitor unit efficiency. However, doses in the vicinity of the irradiated field, i.e. the thyroid, could be relatively high, depending on the VMAT collimator angle. DMLC and SMLC had a large area of relatively high peripheral doses in the breast region.
Division of Radiology, Department of Clinical Technology, Kagoshima University Hospital, 8-35-1, Sakuragaoka, Kagoshima 890-8520, Japan.|Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima 890-8544, Japan.
Masahiko
M
Toyota
Division of Radiology, Department of Clinical Technology, Kagoshima University Hospital, 8-35-1, Sakuragaoka, Kagoshima 890-8520, Japan.
Yasumasa
Y
Saigo
Department of Radiological Sciences, Faculty of Health Sciences, Japan Health Care College, 434-1, Shin-ei, Kiyota-ku, Sapporo 004-0839, Japan.
Kenta
K
Higuchi
Medical Radiation Technology, Kagoshima Medical Technology College, 5417-1, Hirakawa, Kagoshima 891-0133, Japan.
Takuya
T
Fujimura
Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima 890-8544, Japan.
Chihaya
C
Koriyama
Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima 890-8544, Japan.
Takashi
T
Yoshiura
Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima 890-8544, Japan.
Suminori
S
Akiba
D002648:Child; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008953:Models, Anatomic; D058958:Organs at Risk / Q000528:radiation effects*; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated