Safety and Feasibility of Next-Generation Dome Helmet (NGDH) for Focused Ultrasound Neuromodulation in Substance Use Disorder (SUD)

The goal of this clinical trial is to evaluate the safety, feasibility, and preliminary clinical benefit of focused ultrasound (FUS) neuromodulation using the FUS Next Generation Dome Helmet (NGDH) in adults with treatment-resistant moderate-to-severe substance use disorder (SUD). The main questions it aims to answer are: Can FUS neuromodulation be safely delivered to the nucleus accumbens (NAc) and/or anterior insula (aI)? Does FUS neuromodulation result in reduced substance use severity, as measured by Timeline Followback (TLFB), by 4 weeks post-treatment? Participants will: Complete baseline clinical assessments, questionnaires, imaging, and safety assessments. Undergo two MRI-guided FUS neuromodulation sessions approximately 4 weeks apart. Attend follow-up visits for safety monitoring, symptom assessments, quality-of-life measures, and additional imaging where applicable.