The induction of analgesia (see ANALGESICS) by the use of cold that is produced by means of a special probe. The use of cold for the relief of pain dates back to the early days of mankind: two millennia ago, Hippocrates was recommending snow and ice packs as a preoperative analgesic. The modern probe allows a precise temperature to be induced in a prescribed area. Among its uses is in the relief of chronic pain which will not respond to any other form of treatment. This applies particularly to chronic facial pain.