Radiofrequency Ablation of Prelemniscal Radiations for the Treatment of Non-Parkinsonian Tremor.

Objective: Previous reports proposed prelemniscal radiations (Raprl) as a target to treat motor symptoms of Parkinson's disease, and this was found particularly effective to control rest and postural tremor. However, tremor of other etiologies has been seldom treated with deep brain stimulation or ablation in this target. We present a series of such cases successfully treated by Raprl radiofrequency (RF) lesions.

Material And Methods: Six patients with predominant unilateral tremor on the right arm: 4 intention, 1 cerebellar and 1 rubral tremor, incapacitating in spite of at least 2 regimes of medical treatment at maximal tolerated doses, were operated under local anesthesia. RF lesions were performed in Raprl contralateral to most prominent symptoms. Patients had monthly evaluation of tremor severity through the Fahn-Tolosa-Marin Tremor Rating Scale and disability through the Tremor Disability Scale along a 1-year follow-up.

Results: In 4/6 patients tremor was stopped by the simple insertion of an RF electrode in Raprl; in the other 2 cases, stimulation through the RF electrode at 100 Hz, with 100 µs and 1.0-1.5 V, stopped the tremor without side effects. Tremor disappeared in all cases immediately after surgery and partially reappeared in 2 cases with an amplitude about 20% of the preoperative condition. RF lesions in postoperative MRI ranked from 1.8 to 2.6 mm in diameter.

Conclusions: RF lesioning in Raprl is a simple, highly effective, inexpensive way to treat tremor of different etiologies.