Linear Accelerator Radiosurgical Anterior Capsulotomy With Task-based fMRI Identification of PERSonalized and PrEdictiVE Biomarkers of REsponse in Treatment-Refractory Obsessive-Compulsive Disorder (PERSEVERE Trial)

Who can take part

• Age 18 or older at time of enrollment
• Documented diagnosis of Obsessive Compulsive Disorder (OCD)
• Y-BOCS score of 28 or higher confirmed with behavioral testing during pre-existing clinical documentation
• Two trials of selective serotonin reuptake inhibitors for an adequate duration at maximally tolerated dose OR one trial of a selective serotonin reuptake inhibitor with antipsychotic augmentation for an adequate duration at maximally tolerated dose OR one trial of a selective serotonin reuptake inhibitor and clomipramine for an adequate duration at maximally tolerated dose
• Nonresponse to at least one trial of Exposure-Response Prevention behavioral therapy for an adequate duration
• Patient able to understand written and spoken English

Who cannot take part

• Patient has prior ablative procedure to the brain (radiofrequency ablation, thermal ablation, laser interstitial thermal therapy, high-frequency ultrasound)
• Patient has prior diagnosis of brain tumor
• Patient has MRI contraindications (cardiac implantable electronic devices, metallic intraocular foreign bodies, implantable neurostimulation systems, cochlear or ear implants, and drug infusion pumps)
• Patient has comorbid neurodegenerative disorder
• Patient has history of substance use disorder in the past 24 months
• Pregnant women are excluded from this study
• Patient has active suicidal thoughts as assessed by a mental health professional
• Patient deemed by study investigator to lack capacity to provide informed consent