A 22-year study of paroxysmal trigeminal neuralgia in 211 patients with a 3-year appraisal of the role of cryotherapy.

The scope of this investigation included a comparative study of 211 patients with paroxysmal trigeminal neuralgia (PTN) seen over 22 years (from 1959 to 1981) and the use of an open-nerve freezing technique (cryotherapy) on peripheral branches of the trigeminal nerve in 42 of these patients over 3 years (from 1978 to 1981). The study was divided into three parts. Part I was an analysis of clinical findings in all patients. Part II dealt with 33 medically uncontrolled patients and was an assessment of cryotherapy under the most adverse conditions. Part III consisted of an unselected group of 16 patients whose pain could be controlled by chemotherapy but who were not in remission. It was an assessment of cryotherapy in 9 of them as a replacement or adjuvant to chemotherapy. A total of 62 operations were performed, resulting in immediate pain relief and the gradual return of sensation in the treated nerve in all patients. The procedure had to be repeated in 6 patients early in the study to achieve this; one probable reason was inadequate freezing. The longest period of relief has been 2 1/2 years so far; the first patient treated 3 years ago, failed to return and could not be traced. Migration of pain to smaller branches of the trigeminal nerve occurred in 16 patients from 3 to 9 months postoperatively. This was abolished by further cryotherapy in the areas of migration. It is postulated that cryotherapy acts both peripherally and centrally to produce pain relief; if the technique is correctly carried out, the results can be long lasting and may be permanent.(ABSTRACT TRUNCATED AT 250 WORDS)