Where the surface of the treatment volume is convex, the surface of the target volume may protrude into the lumen of the applicator: this phenomenon is known as ‘stand-in’.

Stand-in will act to increase the dose delivered at the surface of the treatment volume


Where the surface of the treatment volume is concave, the surface of the target volume may be at some distance from the face of the applicator: this phenomenon is known as ‘stand-off’.

Stand-off will act to decrease the dose delivered at the surface of the treatment volume


When there is no “stand off”, the treatment time can be read directly from the look up table.

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