Research Article

Similar-Case-Based Optimization of Beam Arrangements in Stereotactic Body Radiotherapy for Assisting Treatment Planners

Table 1

Geometrical features for selection of similar cases.

PTV locationPTV centroid in LR direction
PTV centroid in AP direction
PTV centroid in SI direction

PTV shapeEffective diameter of PTV
Sphericity of PTV

Lung dimensionLung length in LR direction
Lung length in AP direction
Lung length in SI direction

Spinal cord positionDistance between PTV and spinal cord in isocenter plane
Angle from spinal cord to PTV in isocenter plane

PTV: planning target volume; LR: left-right; AP: anterior-posterior; SI: superior-inferior.