P064 rTMS in the treatment of orofacial pain

Abstract

Introduction In our previous experiments 10 Hz and 20 Hz rTMS stimulations were used for the treatment of different types of orofacial pain. All patienst had drug resistant orofacial unilateral neurogenic pain with duration greater than one year. It was found out that 20 Hz rTMS stimulation is more effective than 10 Hz stimulation. In this experiment we tested the theta burst stimulation as another possible tool for pain treatment. Patients 23 patients with 20 Hz, 36 patients with 10 Hz stimulation and 19 patients with theta burst with chronic orofacial pain participated in the study with pharmacotherapy resistant chronic facial pain (trigeminal neuralgia, atypical orofacial pain, post-herpetic neuralgia, dental pain), aged 33–65 years (mean age = 50.7 yrs), with pain duration of at least 6 months. Methods We stimulated motorcortex area corresponding to the hand on painfull side. They underwent quantitative sensory testing before and after the stimulation. The intensity of pain was evaluated in all patients before, during and after rTMS or shame stimulation by means of a visual analogue scale (VAS). Thermal and tactile sensory thresholds and allodynia as a consequence of orofacial pain were measured. The intensity of pain was evaluated in all patients before, during and after rTMS or shame stimulation by means of a visual analogue scale (VAS 0–10). Thermal sensory thresholds and allodynia as a consequences of a neuropathic pain syndrome were measured. Tactile sensory thresholds were measured by using monofilaments (von-Frey) increasing thickness on the affected and nonaffected side. Results By using VAS measurement the theta burst stimulation was more effective than the shame stimulation. The effect of theta burst stimulations was still observed 14 days after the stimulation. Conclusion During the measurement of thermic sensitivity, theta burst stimulation was not significantly improved. The measurement of tactile stimulation was significantly effective after real burst stimulation if compared with shame stimulation. Repetitive transcranial stimulation (rTMS) is non-invasive neuromodulatory technigue that allows safe and painless stimulation of the brain cortex. High frequency rTMS theta burst stimulation was more effective in the chronic orofacial pain and could represent another possibility for the treatment of different types of orofacial pain.