الفهرس 
WartsOnly 14 pages are availabe for public view
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Abstract
Warts are caused by multiple strains of the human papillomavirus (HPV). The virus infects squamous epithelial cells most commonly in acral areas through skin abrasion, but any skin or mucosal surface may be affected.
Approximately 60% of warts regress spontaneously within 2 years. In many cases warts will multiply or continue to enlarge, making treatment more difficult. In addition, many warts are unsightly and may be painful.
Multiple modalities are available for the treatment of warts, but none is uniformly effective. All treatments are hampered by wart persistence and recurrence because of the lack of specific antipapillomavirus agents available for therapy. Warts are only an outward symptom of an underlying infection, and topical treatments do not eradicate HPV.
Destructive methods such as cryotherapy, cantharidin, laser ablation, and surgical excision are variably effective, but are frequently painful and may cause scarring. Moreover, these modalities require individual treatment of each wart, which is especially traumatic for children
Future research is needed to find a superior treatment of viral warts. This research should focus on the development of a specific antiviral therapy for HPV. The most exciting and promising treatments that are appearing on the horizon are the type-specific HPV vaccines.
Cryosurgery literally means ’cold handiwork’. It makes use of local freezing for the controlled destruction or removal of living, but abnormal tissue. Mechanisms by which cryosurgery causes destruction of unwanted tissue are:
1. Intracellular and extracellular ice formation causing mechanical damage to cells.
2. Osmotic changes within the cells due to ice crystal formation that causes cell injury
3. Thermal shock due to fall in the temperature of living cells.
4. Denaturation of lipid protein complexes within the cell membranes.
5. Vascular changes leading to necrosis of the tissue.
6. Immunomodulation.
Of the various refrigerants used, CO2 snow and liquid nitrogen are routinely used by dermatologists. The cryogen is delivered through specialised devices.
A wide spectrum of skin conditions can be treated with cryosurgery. The most common ones are warts and molluscum contagiosum, seborrheic keratosis, melanocytic nevi, developmental anomalies like hemangioma and lymphangioma, cysts, nodular cystic acne, keloids, lentigines, basal cell carcinoma etc.
If done correctly with suitable freezing time, cryosurgery is an efficient, effective, simple and minimally painful procedure. Post treatment care should be taken to prevent secondary infections, scarring and pigmentation.
Lasers have developed markedly over the previous decade, making them a valuable option in many dermatological surgeries. The Er:YAG laser, containing a YAG crystal doped with erbium gas and excited by a pulsed flashlamp, emits light at a shorter wavelength (2490nm). This wavelength corresponds to a peak in water absorption and is 10 times more strongly absorbed by water within the skin cells. Because of this property, the laser has been used to selectively vaporize soft tissue.
The Er:YAG laser has a very short pulse duration, which further limits damage to surrounding areas, in addition to finer ablation and shortened healing time. However, hemostasis is not complete, causing pinpoint bleeding at the dermo-epidermal junction.
The Er:YAG laser has been used in the treatment of warts and it is thought to be effective and safe method used to selectively destroy wart without damaging the surrounding skin. The side effects from Er:YAG laser are limited and infrequent. There is risk of bleeding, infection, pigment change but no scarring.
Although cryotherapy is one of the most established treatment modalities for warts, studies comparing it to more recent lines of treatment are lacking. This study was designed to compare the value of cryotherapy versus Er:YAG laser in the treatment of plantar warts as regards the clinical response, number of sessions required for treatment, rate of recurrence, side effects, and feasibility of either technique.
Our study included 20 patients having more than one plantar wart with age ranging from 19-45 years (mean age 32 years). Two comparable plantar warts were selected in each patient. One was subjected to cryotherapy and the other to Er:YAG laser. The sites were treated in sessions up to three using Er: YAG laser and up to six using cryotherapy according to the clinical response.
The average number of sessions required to produce complete resolution using Er:YAG laser was 1.7 compared to 5.4 using cryotherapy. Complete resolution was achieved in 9(45%) of warts treated by Er:YAG laser and in 5(25%) of warts treated by cryotherapy. Using Er:YAG laser no recurrence was noted in 5(55.5%) patients while recurrence occurred in the other 4(44.5%) patients within three months after treatment. On the other hand, using cryotherapy, no recurrence was noted in 2(40%) patients while recurrence occurred in the other 3(60%) patients within three months after treatment.
We found that Er:YAG laser achieved improvement of the treated plantar warts with fewer sessions, slightly lower recurrence rate, with less incidence of side effects and no big difference in the cost of treatment.