Dosimetric comparison of Gamma Knife® Icon and linear accelerator-based fractionated stereotactic radiotherapy (FSRT) plans for the re-irradiation of large (>14 cm) recurrent glioblastomas.

Our objective is to investigate dosimetric differences between clinically deliverable Gamma Knife (GK) Icon™ and linac-based FSRT plans on the basis of normal brain dose sparing for large (>14 cm) recurrent glioblastomas (GBM). Sixteen patients with large, recurrent GBM were treated using re-irradiation via linac-based FSRT, 35 Gy in 10 fractions. For each patient, a new GK FSRT plan was created in Leksell GammaPlan V11 (LGP).

Geometric and dosimetric effects of image co-registration workflows for Gamma Knife frameless radiosurgery.

The Gamma Knife® Icon™ CBCT facilitates frameless radiosurgery. In the vendor-recommended workflow, MRI is co-registered directly to CBCT for planning. Alternatively, MRI is co-registered to a diagnostic CT, which is then co-registered to CBCT.