Treatment planning for conformal stereotactic radiotherapy

Area of Science:

• Medical Physics
• Radiation Oncology
• Neurosurgery

Background:

• Three-dimensional (3D) planning enables precise dose conformity to intracranial target volumes.
• Advanced patient fixation and positioning systems are crucial for accurate fractionated stereotactic radiotherapy.
• Various irradiation techniques can achieve conformal dose distribution.

Purpose of the Study:

• To compare the efficacy of noncoplanar arc therapy versus conformal static beam therapy for fractionated stereotactic radiotherapy.
• To evaluate dose distributions in the planning target volume (PTV) and organs at risk (OARs) for both techniques.
• To assess the feasibility of achieving precise dose conformation in brain radiotherapy.

Main Methods:

• Utilized three-dimensional planning techniques for dose conformation.
• Employed specialized patient fixation and positioning systems for high repositioning accuracy.
• Compared noncoplanar arc therapy (multiple isocenters) with conformal static beam therapy (single isocenter) using a linear accelerator.
• Calculated and analyzed dose-volume histograms (DVHs) for the planning target volume and normal tissues.

Main Results:

• Both noncoplanar arc and conformal static beam techniques allow for precise dose conformity to the target volume.
• Fractionated stereotactic radiotherapy is feasible with high precision due to advanced patient immobilization.
• DVHs were calculated and discussed, indicating the dose distribution characteristics for both treatment modalities.

Conclusions:

• Three-dimensional planning and specialized immobilization facilitate precise conformal radiotherapy for brain targets.
• Noncoplanar arc and conformal static beam therapies are viable options for fractionated stereotactic radiotherapy, with DVH analysis guiding treatment selection.
• The study highlights the importance of accurate patient positioning and dose planning in optimizing radiation delivery for brain tumors.