Cryotherapy for the Treatment of Verrucae
What is a Verruca?
A Verruca or wart is a viral infection of the skin on the foot. Verrucae can vary in appearance and may occur as single or multiple lesions.
The virus causes an increase in cell replication in the skin and a lump may appear on the skin. If the wart is positioned on the sole of the foot then it may become painful due to the build up of callus.
Verrucae are not usually treated in children. If there is a build up of callus then this may be trimmed off by a Podiatrist / Chiropodist to help alleviate the pain. The Verruca usually stays a few months in children and so should be left alone to let the body fight off the infection and hopefully achieve immunity to the virus. The idea being that if in time the person is later exposed to the virus, they may not pick up another Verruca.
In adults a Verruca can stay a long time, perhaps several years, and treatment may be indicated to help resolve the viral infection.
Cryotherapy
Cryotherapy is one of the treatments available to help resolve a Verruca. Cryotherapy is a controlled destruction of the tissues using very low temperatures i.e. freezing of the skin. Ice is formed inside and outside the cells disrupting the cell where the virus is living.
After freezing the skin is allowed to thaw out. Ideally the treatment ruptures the cells and releases the virus into the blood stream. The body’s immune system is then thought to fight off the skin infection.
Verruca Treatment with a Cryopen
A Cryopen uses nitrous oxide which rapidly freezes the tissues to -89º. It delivers the ice treatment accurately and rapidly. No anaesthesia is required. The probe is held over the Verruca and the skin is frozen for approx 5- 10 seconds.
The skin is then allowed to thaw out for a couple of minutes before the procedure is repeated.
A blister usually develops 24 – 48 hours after the initial freezing treatment.
The lesion may also bleed under the skin so forming a blood blister. This may look alarming but ideally the skin needs to blister to help eradicate the Verruca.
Pain and discomfort may be experienced initially after the blister formation but normally the Cryotherapy is well tolerated by patients.
It is advisable to keep the wound dry and avoid excessive walking or swimming for a few days.
The patient may be reviewed several days later to lance the blister if necessary.
Another review appointment is given 2 -3 weeks after the Cryotherapy when the wound should have healed. Any dead skin is removed and the skin examined to ascertain if the Verruca has resolved.
Some Verrucae are quite stubborn and may require more than one freezing session.
