The effects of gravity on our skin lead to droopiness. Typically, the skin and fat of the face and neck droop to give rise to jowls and a “turkey neck” respectively. The cosmetic effect of these changes is not very nice. Gravity also effects the usually tighter skin of the forehead, which droops and causes the eyebrows to drop down over the eyes. The drooping brow leads to a “sad” look in the face, with excess skin on the upper eyelids that further adds to the tired look. The purpose of the surgery is to elevate the brow up to its normal position, which is at the rim of the eye socket. Removal of the muscles causing lines in the skin is also performed.
Anatomy of the forehead
The forehead area has a relatively simple anatomy compared to other facial regions.
The frontalis muscle spans the length and width of the forehead. This muscle is responsible for the elevation of the eyebrows and, if hyperactive, leads to horizontal brow lines, or “worry lines.”
A circular muscle around the eyes and about 1-2 cm in width is the muscle layer under the eyebrow and in the area just above it. The orbicularis has the function of closing or squinting the eye area.
When Botox is injected too low on the forehead, the frontalis muscle that normally pulls your brow up is deactivated. The remaining effect of the orbicularis will then bring your brow down and cause a droopy brow that will take 2-4 months to get back to normal.
Another set of muscles are the muscles in between the brows that one uses when angry. The glabellar and procerus muscles are also weakened during the surgery to remove the lines they cause.
Nerves of the brow
The main concern with nerves is sensory nerves arising from each side where the eye bone joins the nose. Theses nerves supply sensation to the forehead and the front of the scalp. They are necessarily pulled or injured during forehead surgery and need several months to regrow.
Blood vessels of the forehead
Two minor blood vessels follow the nerves from the nose area up toward the scalp. The blood supply in the scalp is so rich that disruption of these blood vessels is not usually a problem.
In the next segment, I will describe the surgery options available to your plastic surgeon.