الفهرس 
The hair follicleOnly 14 pages are availabe for public view
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Abstract
Hirsutism is increased growth of hair in androgen-dependent sites. It is not only cosmetically disfiguring, but can also be a significant handicap to a young woman’s social life and emotional stability. The laboratory evaluation should be targeted to exclude related disorders. The hormonal therapy can stop new hair from growing and potentially slow the growth of terminal hair already present but can not reverse the terminalization of hair.
The most common techniques of hair removal are bleaching, shaving, tweezing, waxing and depilatories but unfortunately all these methods are temporary, in addition to their side effects. Only electrolysis has some permanent hair removal effect.
Laser epilation has spread in the last years and is highly valued since it is an easy, minimally invasive, painless and extremely effective technique to remove hair. Laser hair removal is accomplished through follicular unit structure destruction. The ability to remove hair without damaging the surrounding skin is based on selective photothermolysis; the theory that states that at a particular wavelength, pulse duration and fluence, thermal injury is confined to the target containing a light absorbing molecule called the chromophore which is the melanin in case of hair shaft. So laser treatment during the anagen (active growth) phase is heterogeneous, but is the only responding hair removal treatment.
Different types of lasers used for hair removal include Ruby laser with a wavelength of 694 nm, (Nd: YAG) laser (1064nm), Diode laser (800nm) and Alexandrite laser (755nm). The Ruby laser is indicated in light-skinned (phototypes I–III) individuals with dark hair. Pigmentary changes has been observed in dark and tanned skin. The diode laser safely induces long-lasting and possibly permanent hair loss with fewer pigmentary side effects than the ruby laser. The continuous wave Nd:YAG laser may cause delay in hair regrowth but no long term side effects or scarring have been described even in dark skin. The Alexandrite laser is effective in the short-term removal of hair in skin types I-V with an acceptable response rate and minimal side effects. Its efficacy varies with respect to the location treated and multiple successive laser treatments are necessary to attain significant long-term epilation.
Hence, the best candidates for laser hair removal are patients with lighter skin (Fitzpatrick type I-IV) and dark brown or black hairs. In addition to the degree of contrast between skin and hair, the color or pigmentation of the hair alone has also been suggested to be a determining factor in the success rate of laser hair removal. Fitzpatrick skins types V and VI respond better after repeated treatments. Skin pigmentation can decrease laser effectiveness and increase side effects. Blonde and gray hairs do not respond to laser treatment as brown or black hairs does. It is unclear whether the use of higher fluences or additional laser sessions might be more successful in treating lighter hair colors.
There is still an increasing demand for safer and more efficient hair removal technique. The latest effective choice in the treatment of hair removal is noncoherent intense pulsed light (IPL) (590 to 1200nm) which is both efficient and safe for hair removal. Both single treatment and multiple treatment sessions result in a dramatic decrease in hair counts immediately following the last treatment, but with longer periods of follow-up, hair regrowth occurred. Also, it has been hypothesized that patients with darker skin color may be able to use this method without problems, although both hyperpigmentation and blistering have been seen after treatment.
Interestingly, the histological changes of the hair follicle after lasers are similar to those described in patients with androgenetic alopecia.
Adverse effects reported after laser-assisted hair removals include erythema, perifollicular edema; which are common, crusting, vesiculation of treatment site and pigmentary changes (depending on skin color and other factors). Most complications are generally temporary. The side effects like folliculitis and purpura are more common with the long pulsed Nd: YAG, whereas hypopigmentation is common with the ruby laser, and hypo and hyperpigmentation with the alexandrite laser; occurred along with crustation and erosion in darker skin types. Caution must be exercised when fluences exceed 20 J/cm and in patients with skin types darker than Fitzpatrick III. In addition, treatment pain is often milder when using higher fluences of the ruby laser or when treating sensitive body areas such as the upper lip or inguinal region than that experienced with the long pulsed Nd: YAG and Alexandrite laser. Also, the Ruby laser and Alexandrite laser produce increased number of complications during the spring and summer most likely due to increased sun exposure and tanning during these seasons. Complication rates also varied according to the anatomic location treated and skin type.