Scalp expansion and scalp extension are done to accommodate scalp reductions when the scalp is too tight. Expansion is also used to prepare individuals for flap surgeries.
Plastic surgeons are the leaders in tissue expansion, a procedure commonly used in reconstructive surgery to repair burn wounds and injuries with significant skin loss. Its use in hair replacement surgery has generated dramatic results -- significant coverage in a relatively short amount of time.
In this technique, a balloon-like device called a tissue expander is inserted beneath hair-bearing scalp that is next to a bald area. The device is gradually inflated with salt water over a period of weeks, causing the skin to expand and grow new skin cells. This causes a bulge beneath the hair-bearing scalp, especially after several weeks.
When the skin beneath the hair has stretched enough -- usually about two months after the first operation -- another procedure is performed to bring the expanded skin over to cover the adjacent bald area.
Lasers were first used in hair transplantation in 1992. Results were variable (in some instances, the use of strong continuous beam lasers caused traumatic injuries) and the procedure remains controversial today.
Newer, safer technology has been developed and approved by the FDA, especially in the area of pulsating lasers (see How Tattoo Removal Works). However, laser surgery still isn't a mainstream hair replacement option. In this procedure, the laser's light beam is rapidly pulsed up to hundreds of times per second. This avoids heat buildup and preserves the vascular layers of the scalp.
Laser recipient sites are generally holes ranging in size from 0.3 to 0.8 millimeters. (Some surgeons prefer to use strip grafts -- again, doctors disagree on this subject.) Small amounts of bald tissue are removed with each pulse of the laser. This prevents any compression of the newly placed grafts. After all the recipient sites are made, a small probe is used to enter the scalp's vascular layer -- a procedure that must take place without damaging the vascular layer's components.
As with conventional transplant surgery, local anesthetic is used, preceded by an analgesic cream that helps to reduce the injection's sting. The donor area is then harvested using simple scalpel techniques (the laser doesn't do the job here). After the donor grafts or strips have been removed, the area is sealed with an infrared coagulation device and then closed with sutures. Sutures are removed in 10 days in most cases.