Yes, this is a tough situation to stack.
What happens is that the bright spots "slide around" in interesting ways as the subject goes into and out of focus. PMax tends to show those at all their different positions, resulting in nasty streaks. DMap can usually be talked into doing a better job, and DMap will definitely solve the problem with contrast enhancement. But even in the best case DMap is going to need some hand-holding in the form of careful setting of the threshold slider, and quite likely some manual retouching.
See
http://www.photomacrography.net/forum/v ... hp?t=16736 for some discussion of closely related effects in a different photographic setup.
--Rik