Is there a limit on the number of brain metastases that can be safely treated with single-isocenter multitarget linac-based SRS using HyperArc?

When thinking about this particular question, one would have to define which metrics would be dose limiting. Most would consider a mean brain dose of about 8 Gy to be the maximum tolerated dose to the normal tissue. This could be modeled in HyperArc and is a function of the number of tumors and volu...