Predicting tremor improvement after MRgFUS thalamotomy in essential tremor from preoperative spontaneous brain activity:A machine learning approach

术前自发脑活动预测特发性震颤MRgFUS丘脑切除术后震颤改善:一种机器学习方法

Magnetic resonance-guided focused ultrasound surgery(MRgFUS)thalamotomy is an emerging technique for medication-refractory essential tremor(ET),but with variable outcomes.This study used pattern regression analysis to identify brain signatures predictive of tremor improvements.Fifty-four ET patients(mean age=63.06 years,standard deviation(SD)=10.55 years,38 males)underwent unilateral MRg FUS thalamotomy and were scanned for resting-state functional magnetic resonance imaging(rsf MRI).Seventy-four healthy controls(mean age=58.09 years,SD=10.30 years,38 males)were recruited for comparison.Tremor responses at 12 months posttreatment were evaluated by the Clinical Rating Scale for Tremor.The fractional amplitude of low-frequency fluctuations(f ALFF)was calculated from rs-f MRI data.Two-sample t-test was used to generate a disease-specific mask,within which Multivariate Kernel Ridge Regression analyses were conducted.Predicted and actual clinical scores were compared using Pearson's correlation coefficient(r)and normalized mean squared error(Norm.MSE).Permutation test and leave-one-out strategy were applied for results validation.KRR identified f ALFF patterns that significantly predicted the hand tremor improvement(r=0.23,P=0.025;Norm.MSE=0.05,P=0.026)and the postural tremor improvement(r=0.28,P=0.025;Norm.MSE=0.06,P=0.023),but not action tremor improvement.Lobule VI of right cerebellum(Cerebelum_6_R),right superior occipital gyrus(Occipital_Sup_R)and lobule X of vermis(Vermis_10)contributed most for hand tremor prediction(normalized weights(NW):2.77%,2.40%,2.34%)while Vermis_10,left supplementary motor area(Supp_Motor_Area_L)and right hippocampus(Hippocampus_R)for postural tremor prediction(NW:2.69%,2.12%,2.05%).The low contributing NW of the individual brain regions suggested that the f ALFF pattern as a whole is an overall predicting feature.Preoperative f ALFF pattern predicts tremor benefits induced by MRg FUS thalamotomy.Clinical Trials.gov number:NCT04570046.