RT Journal Article
SR Electronic
T1 Connectomic Basis for Tremor Control in Stereotactic Radiosurgical Thalamotomy
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 157
OP 164
DO 10.3174/ajnr.A7778
VO 44
IS 2
A1 E.H. Middlebrooks
A1 R.A. Popple
A1 E. Greco
A1 L. Okromelidze
A1 H.C. Walker
A1 D.A. Lakhani
A1 A.R. Anderson
A1 E.M. Thomas
A1 H.D. Deshpande
A1 B.A. McCullough
A1 N.P. Stover
A1 V.W. Sung
A1 A.P. Nicholas
A1 D.G. Standaert
A1 T. Yacoubian
A1 M.N. Dean
A1 J.A. Roper
A1 S.S. Grewal
A1 M.T. Holland
A1 J.N. Bentley
A1 B.L. Guthrie
A1 M. Bredel
YR 2023
UL http://www.ajnr.org/content/44/2/157.abstract
AB BACKGROUND AND PURPOSE: Given the increased use of stereotactic radiosurgical thalamotomy and other ablative therapies for tremor, new biomarkers are needed to improve outcomes. Using resting-state fMRI and MR tractography, we hypothesized that a “connectome fingerprint” can predict tremor outcomes and potentially serve as a targeting biomarker for stereotactic radiosurgical thalamotomy.MATERIALS AND METHODS: We evaluated 27 patients who underwent unilateral stereotactic radiosurgical thalamotomy for essential tremor or tremor-predominant Parkinson disease. Percentage postoperative improvement in the contralateral limb Fahn‐Tolosa‐Marin Clinical Tremor Rating Scale (TRS) was the primary end point. Connectome-style resting-state fMRI and MR tractography were performed before stereotactic radiosurgery. Using the final lesion volume as a seed, “connectivity fingerprints” representing ideal connectivity maps were generated as whole-brain R-maps using a voxelwise nonparametric Spearman correlation. A leave-one-out cross-validation was performed using the generated R-maps.RESULTS: The mean improvement in the contralateral tremor score was 55.1% (SD, 38.9%) at a mean follow-up of 10.0 (SD, 5.0) months. Structural connectivity correlated with contralateral TRS improvement (r = 0.52; P  = .006) and explained 27.0% of the variance in outcome. Functional connectivity correlated with contralateral TRS improvement (r = 0.50; P  = .008) and explained 25.0% of the variance in outcome. Nodes most correlated with tremor improvement corresponded to areas of known network dysfunction in tremor, including the cerebello-thalamo-cortical pathway and the primary and extrastriate visual cortices.CONCLUSIONS: Stereotactic radiosurgical targets with a distinct connectivity profile predict improvement in tremor after treatment. Such connectomic fingerprints show promise for developing patient-specific biomarkers to guide therapy with stereotactic radiosurgical thalamotomy.BOLDblood oxygen level–dependent MRIDBSdeep brain stimulationDRTTdentato-rubro-thalamic tractSMSsimultaneous multisliceSRSstereotactic radiosurgeryTRSFahn‐Tolosa‐Marin Clinical Tremor Rating ScaleVIMventral intermediate nucleus