title: Surface dose with grids in electron beam radiation therapy.
abstract: This investigation attempts to solve the problem of the lack of skin-sparing effect in electron radiation therapy and to increase the tolerance of skin to radiation using the grid technique. Electron grid therapy involves the mounting of a Cerrobend grid in the electron cone. Film dosimetry was employed to measure the relative surface dose and the percentage depth dose profile of electron grid portals. Various grid hole diameters (d = 0.45, 1.0, 1.5 cm) and grid hole spacings (s = 0.4, 0.2 cm) were considered for electron beams from 6 to 14 MeV. Experimental results indicate that the electron grid technique can reduce the relative surface dose in electron radiation therapy. Degradations of the relative surface dose depend on the percentage of open area in the grid portal. A proper grid design allows the surface dose to be reduced and the range of nonhomogeneous doses to be limited to a depth at which the target volume can receive a homogeneous dose. The grid technique can lower the surface dose in electron radiation therapy.
authors.affiliation: Department of Nuclear Science, National Tsing Hua University, Hsinchu, Taiwan, ROC.
authors.forename: Kuei-Hua
authors.initials: KH
authors.lastname: Lin
authors.forename: Chao-Yuan
authors.initials: CY
authors.lastname: Huang
authors.forename: Jao-Perng
authors.initials: JP
authors.lastname: Lin
authors.forename: Tieh-Chi
authors.initials: TC
authors.lastname: Chu
mesh_terms: D004583:Electrons / Q000627:therapeutic use*; D005373:Film Dosimetry; D006801:Humans; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy / Q000379:methods* / Q000706:statistics & numerical data; D012867:Skin / Q000528:radiation effects; D013679:Technology, Radiologic