Which normal brain dosimetric constraints are most important when treating brain mets with SRS?
How should they be prioritized? V10, V12, mean brain dose, prior WB radiation? To what extent should tumor coverage, conformality and homogeneity be compromised to achieve these goals?
Answer from: Radiation Oncologist at Community Practice
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...
Answer from: Radiation Oncologist at Community Practice
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...
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Radiation Oncologist at Lake Huron Medical Center Where does that Normal Brain PTV - 28.8 Gy < 7cc c...
Radiation Oncologist at Vanderbilt-Ingram Cancer Center For 3 Fraction SRT, we routinely use Minniti data ...
Radiation Oncologist at Karmanos Cancer Institute - McLaren Proton Therapy Center For a more in-depth explanation of the 5 fraction ...