HI cwanal1,

I believe this is what you are looking for.......

Radiofrequency Lesion or Alcohol Block

The easiest way to create a temporary lesion in the second (middle) or third (lower) branch of the nerve is to use a radiofrequency technique in which the needle is positioned in the nerve outside of the skull. An alternate method is to inject alcohol into the nerve at these sites. The disadvantage of the alcohol injection is that it is difficult to repeat because scarring develops in the nerve which prevents the alcohol from getting into the nerve on subsequent injections. The numbness associated with an alcohol injection or a radiofrequency lesion in a superficial location outside the skull usually lasts from two to 12 months. If there is satisfactory pain relief with a temporary lesion and the numbness is not unpleasant a permanent type of radiofrequency lesion can be done when the pain recurs. If the numbness was especially unpleasant because of a tingling or burning feeling in the numb area, a vascular decompression procedure could be done when the pain recurs. Alcohol injections may be used to numb the forehead, but are less effective for the first branch of the nerve than for the second or third branches.

Hope this helps Nikki