Thin-sliced CT and high-resolution MRI imaging with 1.0 mm in slice thickness and gadolinium contrast were employed for contouring the gross target volume (GTV). CT to MRI fusion was used to eliminate the potential distortion of MRI images. GTV was calculated using the iPlan Radiotherapy Planning Software (iPlan RT Image 3.0.1, Brainlab, Germany). The Novalis treatment system (Brainlab, Heimstetten, Germany) along with the software Brainscan, version 5.31 (Brainlab, Germany) was used to design the treatment plan. The use of precise micro-multileaf collimators in the Novalis system is able to shape the dose and minimize exposure of surrounding normal tissues by a single isocenter. A 100% isodose line was employed to cover the target.
During treatment, the patients were immobilized with a Brainlab thermoplastic fixation mask and an oral bite. A stereoscopic X-ray system combined with an infrared position tracking system was used to ensure the correct position.
Oral dexamethasone (0.5 mg 4-times-a-day for 3 consecutive days in SSRS and 7 consecutive days in FSRT) was given to the patients from the first day of treatment to prevent acute toxic effects induced by radiosurgery.
During treatment, the patients were immobilized with a Brainlab thermoplastic fixation mask and an oral bite. A stereoscopic X-ray system combined with an infrared position tracking system was used to ensure the correct position.
Oral dexamethasone (0.5 mg 4-times-a-day for 3 consecutive days in SSRS and 7 consecutive days in FSRT) was given to the patients from the first day of treatment to prevent acute toxic effects induced by radiosurgery.