The Optimal Targeting for Focused Ultrasound Thalamotomy Differs between Dystonic and Essential Tremor: A 12-Month Prospective Pilot Study

BackgroundMagnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is increasingly used to treat drug-resistant essential tremor (ET). Data on MRgFUS thalamotomy in dystonic tremor (DT) are anecdotal.ObjectivesTo investigate efficacy, safety, and differences in target coordinates of MRgFUS thalamotomy in DT versus ET.MethodsTen patients with DT and 35 with ET who consecutively underwent MRgFUS thalamotomy were followed for 12 months. Although in both groups the initial surgical planning coordinates corresponded to the ventralis intermediate (Vim), the final target could be modified intraoperatively based on clinical response.ResultsTremor significantly improved in both groups. The thalamic lesion was significantly more anterior in DT than ET. Considering both ET and DT groups, the more anterior the lesion, the lower the odds ratio for adverse events.ConclusionsMRgFUS thalamotomy is safe and effective in DT and ET. Compared to classical Vim coordinates used for ET, more anterior targeting should be considered for DT.

Automated summary

This study investigated the efficacy, safety, and target coordinates of MRgFUS thalamotomy in dystonic tremor (DT) compared to essential tremor (ET). The results showed that MRgFUS thalamotomy is safe and effective in both DT and ET. Targeting coordinates should be more anterior for DT compared to ET.