After incisional or alcoholic destruction of trigeminal posterior rootlets, constant dysesthesias
of major degree referred to some part of the markedly denervated zone develop in 5 to 15%
of the patients. The full severity may not appear for weeks or months. There is no allodynia
or hyperpathia of the denervated zone. Bulbar trigeminal tractotomy with sparing of touch
sensation produces severe dysesthesias in a tiny percentage of the patients, as does
selective destruction of pain fibers by radiofrequency heating or glycerol. Spinal posterior …