The causes of poor hair growth after surgery
There are a number of factors that can contribute to poor hair growth after surgery. Some have preoperative causes, while others result from something that happens during or after the surgery.
The most common preoperative factors include cigarette use, diabetes, vascular disorders and undiagnosed Cicatricial Alopecia – which is a rare disorder that destroys hair follicles and leaves scarring in their place.
A common cause of poor hair growth after surgery resulting from the surgery itself is tissue damage during the harvesting, trimming and insertion process. During harvesting, hairs may be severed, as hair angles and depths vary throughout the scalp. To ensure this damage does not occur, it is necessary for surgeons to have good visuals from a microscope during the graft placement. They also need to keep all eyes on the target, meaning the placers need to limit the number of times they look away from the recipient sites to avoid losing the positions and increasing the chance of missed.
Another cause of poor hair growth post surgery is grafts that become dehydrated. The most vulnerable time for this is during graft insertion, as irreversible damage can occur within minutes outside of a wet environment. To prevent damage, it is necessary to store tissue in a cool, hydrated medium. The most effective way to do this has yet to be determined. Presently, the most common and least expensive storage solution is normal saline. When grafts are not in the solution, they must be sprayed frequently. It also is important to limit the number of grafts taken out of the solution at one time and placed on a finger for implantation.
To ensure graft survival and post-operative growth, atraumatic growth insertion is necessary – meaning there is minimal tissue injury during the process.
Some physicians feel that “dense packing’, meaning transplanting more than 30 follicular units in a square centimeter causes a poor survival rate after hair restoration surgery. When too many are transplanted, it seems the grafts surrounding the dense area do well, while the ones placed centrally, do not. It is possible to compromise the blood supply to centrally placed grafts by packing the perimeter grafts too tightly.
Other factors that could impact hair growth following surgery are the time the graft is spent out of the body, the density of the recipient site, and scalp trauma related to the depth and width of the incision.
To ensure hair growth, it also is necessary that post-operative hygiene is kept up, and that any inflammation is reduced. Infection and poor healing could also lead to reduced growth after surgery.