Can Ultherapy performed on the forehead (brow lift) affect the frontal lobe of the brain in any way?

Ultherapy performed on the forehead for a brow lift would not affect the brain.  The brain is too deep to be affected by the treatment.  

Given that you would even think of this question, I would highly suggest you have a detailed conversation with your treating doctor before deciding to have such a treatment as I suspect there may be more concerns and general anxieties which may not make you a good candidate for an elective cosmetic procedure.

Thank you for your question.  Ultherapy will never penetrate deep enough to affect brain matter.  If it were to penetrate deeper than the skin, the energy generated by the ultrasound would be absorbed by the bone (your skull) before it ever got close to heating your brain tissue.  Regards, Dr. Matt Elias

Ultherapy uses high intensity focused ultrasound. Even IF energy penetrates deeper, it would be absorbed by bone as it has higher attenuation coefficient. I have 3 ultrasound credentials and I can assure you that energy will not travel to brain tissue. See the link below. H Karamanoukian MD FACS RVT RPVI RPhS

The depth of the 4.5mm probe is less that one half a centimeter that is around a quarter of an inch.  The brain is never that close to the surface.  So be assured, the brain will not be heated by Ultherapy.

HIFU at 4.5 mm will not penetrate the bone. Your frontal bone is so thick that there is no way HIFU from Ultherapy will penetrate the bone, and have energy transmitted to your brain.If you do a search on a 9mm bullet fired at 25 m, in some cases, at the correct angle, even this does not penetrate the frontal bone (both due to the angle of bossing and thickness). Obviously I don't suggest anyone try this, but its an illustration as to how thick and strong the frontal bone is. Kind regardsDr Davin LimLaser and aesthetic dermatologistBrisbane, Australia.