%0 Journal Article
%T Probabilistic Refinement of Focused Ultrasound Thalamotomy Targeting for Parkinson's Disease Tremor.
%A Cheyuo C
%A Germann J
%A Yamamoto K
%A Zibly Z
%A Krishna V
%A Sarica C
%A Borges YFF
%A Vetkas A
%A Kalia SK
%A Hodaie M
%A Fasano A
%A Schwartz ML
%A Elias WJ
%A Lozano AM
%J Mov Disord
%V 0
%N 0
%D 2024 Aug 9
%M 39120112
%F 9.698
%R 10.1002/mds.29965
%X <B>BACKGROUND: </B>There remains high variability in clinical outcomes when the same magnetic resonance image-guided focused ultrasound (MRgFUS) thalamotomy target is used for both essential tremor (ET) and tremor-dominant Parkinson's disease (TDPD).<BR><B>OBJECTIVE: </B>Our goal is to refine the MRgFUS thalamotomy target for TDPD versus ET.<BR><B>METHODS: </B>We retrospectively performed voxel-wise efficacy and structural connectivity mapping using 3-12-month post-procedure hand tremor scores for a multicenter cohort of 32 TDPD patients and a previously published cohort of 79 ET patients, and 24-hour T1-weighted post-MRgFUS brain images. We validated our findings using Unified Parkinson's Disease Rating Scale part III scores for an independent cohort of nine TDPD patients.<BR><B>RESULTS: </B>The post-MRgFUS clinical improvements were 45.9% ± 35.9%, 55.5% ± 36%, and 46.1% ± 18.6% for ET, multicenter TDPD and validation TDPD cohorts, respectively. The TDPD and ET efficacy maps differed significantly (ppermute < 0.05), with peak TDPD improvement (87%) at x = -13.5; y = -15.0; z = 1.5, ~3.5 mm anterior and 3 mm dorsal to the ET target. Discriminative connectivity projections were to the motor and premotor regions in TDPD, and to the motor and somatosensory regions in ET. The disorder-specific voxel-wise efficacy map could be used to estimate outcome in TDPD patients with high accuracy (R = 0.8; R2 = 0.64; P < 0.0001). The model was validated using the independent cohort of nine TDPD patients (R = 0.73; R2 = 0.53; P = 0.025-voxel analysis).<BR><B>CONCLUSIONS: </B>We demonstrated that the most effective MRgFUS thalamotomy target in TDPD is in the ventral intermediate nucleus/ventralis oralis posterior border region. This finding offers new insights into the thalamic regions instrumental in tremor control, with pivotal implications for improving treatment outcomes. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.