Treatment planning optimization for linear accelerator radiosurgery.
OBJECTIVE
Linear accelerator radiosurgery uses multiple arcs delivered through circular collimators to produce a nominally spherical dose distribution. Production of dose distributions that conform to irregular lesions or conformally avoid critical neural structures requires a detailed understanding of the available treatment planning parameters.


METHODS
Treatment planning parameters that may be manipulated within a single isocenter to provide conformal avoidance and dose conformation to ellipsoidal lesions include differential arc weighting and gantry start/stop angles. More irregular lesions require the use of multiple isocenters. Iterative manipulation of treatment planning variables can be difficult and computationally expensive, especially if the effects of these manipulations are not well defined. Effects of treatment parameter manipulation are explained and illustrated. This is followed by description of the University of Florida Stereotactic Radiosurgery Treatment Planning Algorithm. This algorithm organizes the manipulations into a practical approach for radiosurgery treatment planning.


RESULTS
Iterative treatment planning parameters may be efficiently manipulated to achieve optimal treatment plans by following the University of Florida Treatment Planning Algorithm. The ability to produce conformal stereotactic treatment plans using the algorithm is demonstrated for a variety of clinical presentations.


CONCLUSIONS
The standard dose distribution produced in linear accelerator radiosurgery is spherical, but manipulation of available treatment planning parameters may result in optimal dose conformation. The University of Florida Treatment Planning Algorithm organizes available treatment parameters to efficiently produce conformal radiosurgery treatment plans.
Meeks
S L
SL
Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, USA.
Buatti
J M
JM
Bova
F J
FJ
Friedman
W A
WA
Mendenhall
W M
WM
D000465:Algorithms; D001932:Brain Neoplasms / Q000556:secondary / Q000601:surgery; D003480:Cushing Syndrome / Q000601:surgery; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery; D009464:Neuroma, Acoustic / Q000601:surgery; D016634:Radiosurgery / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*