Imaging characteristics correlated with outcomes of cranial MRgFUS - a systematic review

While research on imaging correlates of magnetic resonance guided focused ultrasound (MRgFUS) outcomes accumulates, a comprehensive synthesis across different disease populations remains absent. This systematic review aims to identify, technique-specific imaging biomarkers linked to treatment outcomes across distinct clinical conditions, including essential tremor (53 studies), Parkinson's disease (8 studies), and psychiatric disorders (2 studies). Key findings demonstrate that in ET, larger ventral intermediate nucleus (Vim) lesions intersecting the dentatorubrothalamic tract (DRTT) correlate with greater tremor reduction but increased adverse event risks. Diffusion tensor imaging (DTI) and resting-state functional MRI (rs-fMRI) revealed post-treatment white matter remodeling and functional restoration within sensorimotor, cerebellar, and visual networks. For PD, symptom improvement depended on ablation specificity within subthalamic nucleus (STN) or Vim subregions, with pre-treatment connectivity to motor cortices serving as predictive markers. Limited psychiatric studies implicated anatomical targeting and lesion-related functional connectivity in treatment response. The review concludes that lesion characteristics and brain connectivity are pivotal for optimizing MRgFUS strategies and outcomes across diseases.