The matching of adjacent fields in radiotherapy.

Radiology (Impact Factor: 6.21). 09/1973; 108(2):419-22. DOI: 10.1148/108.2.419
Source: PubMed
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    ABSTRACT: When the whole neuraxis is irradiated, as in medulloblastoma, the large target volume makes field arrangement complicated and 3-4 adjacent fields have to be used. A calculation method, based on geometrical matching of field edges, is presented for determining optimal separation between the opposed cranial fields and the posterior spinal field as orthogonal movements of the treatment couch top. The dosimetric verification of the method with a 4 MV photon beam indicates a dose inhomogeneity below +/- 7%.
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    ABSTRACT: The digital display of the simulator couch position is an often under utilized accessory. This function can be very helpful in determining patient separation and posterior source-to-skin distance (SSD) and also in the setting up of abutting and preplanned ports. Examples are presented to show the practical application for routine simulations.
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