A Comparison of Whole-Brain Dose During Stereotactic Radiosurgery for Multiple Metastases Across Technology Platforms

Stereotactic radiosurgery (SRS) is now the gold standard radiation technique for the treatment of multiple brain metastases. By virtue of its targeting accuracy, SRS, relative to whole-brain radiotherapy (WBRT), maximizes both the likelihood of tumor ablation while minimizing irradiation (injury) of the uninvolved brain. The extent to which the latter objective is accomplished varies among radiosurgery platforms. In this study, we used a standardized imaging dataset taken from a patient with 10 random brain metastases to calculate the radiation dose delivered to the uninvolved normal brain across a range of modern SRS delivery platforms. This analysis reveals that irradiation of the uninvolved brain is considerably less on dedicated cranial SRS devices compared to multi-purpose C-arm and full-body robotic systems. Given the growing recognition of lower-dose radiation's deleterious effects, these findings may have relevance to patient and technology selection.