Androgenetic alopecia (pattern baldness) is the cause of hair loss in men and women in over 90% of cases. This is an inherited form of hair loss that is then triggered by hormones any time after puberty and is defined as hair loss at the front, top and/or the crown/vertex of the scalp (non-permanent area). The back and sides of the scalp are spared and usually grow hair for life (permanent area). Traditional treatments include medications such as minoxidil and finasteride (men only) and hair transplantation. There are many other causes for hair loss some of which may be treated with surgery.
These include alopecia areata (AA), a condition the cause of which we do not yet know, but which may be autoimmune. The progression of the condition is usually unpredictable and often does not respond to treatment. Pattern baldness is so common it often coexists with alopecia areata.
There are some forms of AA that mimic the same pattern as genetic baldness so correct diagnosis is important. With hair loss in women in particular a number of conditions result in the same diffuse pattern in which the hair over the top and crown of the head becomes thinner (occasionally the temples will recede too). There is often some investigation needed to first isolate the cause before working on a treatment.
Normally we shed an average of 100 hairs per day. Fortunately these hairs are replaced; but, when these lost hairs are not replaced or when the daily shedding exceeds the normal, then true hair loss occurs. In AA the hair loss is often localized to one or more discrete patches that become totally bald. These patches may go away of their own accord, may resolve following medical treatment or may stay unchanged long term. It is those patches that stay long term that we may be able to treat with surgery.
Modern hair transplant techniques have introduced a new era in the treatment of hair loss for both men and women. The surgery performed is called follicular unit grafting. This involves the removal of a strip of hair bearing scalp from the back of the head then stitching the area. The hair above the surgery site will disguise the stitches until they heal. The strip of skin and hair is then dissected under microscopes to isolate the follicular units (these are small groups of hair that contain 1-4 hairs). Each follicular unit or graft is then inserted into a small incision made in the bald area. We normally place 20-40 of these grafts in each square centimeter of bald scalp. The procedure is done as a day case under local anaesthetic.
The patients with AA that are generally accepted for surgical hair restoration are those with one or a few small patches that have remained unchanged and have not been treated medically for several years. This is usually a minimum of two years. With one operation we can achieve about 30% of the original density so some patients may require 2 operations to achieve a thicker look. Unfortunately it cannot be guaranteed that the hair will be permanent as the disease process can recur at any time. But for some patients even a temporary return to ‘normal’ hair is acceptable.