Hi all,

I thought I was the only dinosaur left using a cotton swab and a styrofoam cup.....

Material list:

Liquid nitrogen Dewar, about 25 liter (big thermos bottle)
Ladel (usually carried by N2 supplier)
Styrofoam cup (coffee cup)
6" cotton swab
Cotton ball

The key is to wrap more cotton around the cotton swab. The cotton is wound too tightly to hold much N2. Pull some cotton off the cotton ball, and wrap it around the cotton alrady on the swab. I usually try to double the size of the cotton. This technique takes a little practice to learn.

Then put a ladelful (10 ccs or so) of N2 in a styrofoam cup. Just hold the cup normally, the outside will only get slightly cool. Dip the swab into the N2 for a few seconds, then apply yo the lesion. After 5 or 10 seconds, redip and reapply. When frozen, the lesion will be white in color.

Warts should be frozen longer, with about a 1 mm ring of frost extending into the surrounding skin. Actinic and sebaooheic keratoses need to be frozen in their entirety.

If the patient is a child, the best is yet to come. Lots of ways to have fun with the remaining N2!

Hope this helps. Gene

Gene Nallin MD solo family practice with one PA Cumberland, Md