Brow bone reduction alters the amount of forward projection of the lower third of the forehead. When it is a craniofacial bone reduction procedure it is unique because of the underlying frontal sinus. This is true for at least the inner half of the brow bones whose shape is controlled by the size of the frontal sinus. (the outer half of the brow bones is solid bone)
As a result of this anatomy performing brow bone reduction by burring alone has its limitations. Beyond a few millimeters of bone removal the frontal sinus air space is encountered. This is why more significant reductions require a bone flap technique where the outer table bone of the frontal sinus is removed, reshaped and then replaced.
But between burring and a total bone flap removal lies an intermediary procedure brow bone reduction procedure. There is when the combination of partial or subtotal bone flaps are removed and then combined with burring. Instead of removing one single large bone cell across the whole frontal sinus, two smaller individual bone flaps are removed. The bone that is removed is the most projecting part or thinnest area of the anterior table of the frontal sinus.
Once these smaller bone flaps are removed, burring is done over the remaining outer table of the frontal sinus bone reducing it a few millimeters but leaving it intact. The small removed bone flaps are then. inverted and replaced back into the defect site restoring the bony outer table.
This modified brow bone reduction technique is a good method for some male patients who want the amount of projection reduced but still want to have some remaining brow bone projection. It can also be useful in some select transgender patients whose brow bone projections are more modest in size.
Dr. Barry Eppley