Treatment of tic douloureux by percutaneous retrogasserian glycerol injection.

Thirty patients with tic douloureux underwent treatment by percutaneous retrogasserian glycerol injection (PRGI). All patients had symptomatic trigeminal neuralgia refractory to medical therapy. Fifteen patients had recurrent tic after one to four prior operations. The technique was simple to perform and required no intraoperative physiological testing or short-acting barbiturate supplementation during transovale placement of a spinal needle in the trigeminal cistern of Meckel's cave. Precise placement of small volumes (0.15 to 0.35 mL) of sterile glycerol was ensured by first demonstrating the anatomy of the trigeminal cistern using metrizamide. Overall, 23 patients have remained pain free five to 12 months after treatment. Nineteen patients had no change in facial sensation after injection. Treatment by PRGI is a valid alternative therapy for tic douloureux, with the additional benefit of a much-reduced incidence of facial sensory loss when compared with differential thermal rhizotomy by a radiofrequency-induced lesion technique. Facial deafferentation is not mandatory for successful percutaneous treatment of tic douloureux.