Focused Ultrasound for the Complex Patient
The goal of this clinical trial is to to inhibit the anterior insula (AI) with low intensity focused ultrasound (LIFU) to determine the causal role for the AI in pain processing, anxiety, and opiate cue-induced craving. The main question\[s\] it aims to answer are: * the safety and tolerability of LIFU delivered bilaterally to AI compared to sham stimulation in individuals with opiate use disorder (OUD), anxiety, and chronic back pain * the effects of LIFU vs sham on measures of pain processing, anxiety symptoms, and opiate cue-induced craving Participants will undergo anatomical MRI, neurological assessment, clinical assessment and patient query to assess the safety and tolerability of LIFU vs sham.