Facial pain relieved by dorsal root entry zone lesions in the trigeminal nucleus caudalis: report of two cases.

Microvascular decompression by suboccipital craniectomy often cures medically untreatable trigeminal neuralgia. However, pain involving the same distribution persists in a few patients despite surgical treatment. In two cases, one with postherpetic pain and the other with tic douloureux, the author used the radiofrequency lesion technique in the dorsal root entry zone of the trigeminal nucleus caudalis to treat the surgically-failed cases of trigeminal neuralgia. The pain ceased postoperatively and has not recurred during three to four years of follow-up. Trigeminal nucleus caudalis surgery provides a satisfactory solution to this relatively rare pain syndrome.