How Much Can The Bony Temporal Lines (Forehead Width) Be Reduced?

Q: Dr. Eppley, my forehead looks overly wide, compared to the bigonial width and the outer lateral orbital walls. From your experience (and I know it might differ for every human) what is the maximum safe reduction that can be done?

Also, from the side profile my forehead looks straight, from brows to the beginning of the hairline. Could the bony part right at the beginning of the hairline to be reduced as well? (downward direction) 

A: The thickness of the bony temporal line is greater than that of the forehead bone between it….4 to 5mms can be easily reduced. The upper forehead at the transition of the forehead and top of the skull can also be reduced in the 3 to 4mm range.

Dr. Barry Eppley

World-Renowned Plastic Surgeon