Do you place any constraint on Dmax when developing plans for linac-based SRS or SBRT?  

Very rarely.  I was a gamma knife SRS person before I started linac-based SRS so I am very comfortable with >120% hot spots.  For brain linac based SRS we regularly push hotspots to 150% to get the steepest dose falloff (most similar to gamma knife plans prescribing to the 50%...

This is the number one thing I see leading to poor quality in linac SRS and SBRT plans, especially when reviewing plans from dosimetrists and physicists who trained on linacs in the era before linac SRS and SBRT became more common. Merely the act of asking in your cost function for homogeneity...

Agree with the hotspot notion. First, we have long history of knowing that it's safe (particularly without intervening OAR). Second, it may well be a driver of control! See our publication on this. Hotspots are a natural consequence of creating highly conformal 3D plans, where the collimator or bloc...