Which normal brain dosimetric constraints are most important when treating brain mets with SRS?

It sounds like you may be starting a new radiosurgery program. May I suggest that if your normal brain tolerance constraints cannot be met with single fraction SRS, or you are worried about tolerance due to prior radiation, consider hypofractionation with 3 or 5 fractions. For 5 fractions x 6 Gray, ...

Great point, esp. about the PTV margin issue. Some people argue you don't really need to add a mm or two of margin; "We have sub-mm localization error." A 0.7 mm error in three single dimensions equals a 1.2 mm error for the scalar in 3D (as 1.2 = ((0.7^2)+(0.7^2)+(0.7^2))^0.5), so I think it's a si...