prescription isodose line
The isodose curve that represents the prescribed radiation dose level, typically encompassing the target volume.
Full Definition
The prescription isodose line is a specific dose contour line that corresponds to the prescribed treatment dose, usually expressed as a percentage of the maximum dose or as an absolute dose value. This isodose line should ideally encompass the entire planning target volume while minimizing coverage of normal tissues. The prescription isodose line is fundamental to plan evaluation and must meet specific coverage criteria defined by institutional protocols or clinical trial requirements. Common prescription levels include 95% for conventional treatments or 80% for stereotactic procedures.
Usage
Usage note: May be abbreviated as 'Rx isodose' in informal contexts.
In Context
- "The prescription isodose line covered 98% of the planning target volume." — Plan evaluation report
- "Prescription isodose line selection affects normal tissue dose distribution." — Treatment planning guideline